Drought! Finding New Signals for Plant Cells
Scientists have found a signal in plants which may act as a drought alarm, allowing them to adapt to drought conditions.
The signal was discovered while trying to understand how different parts of the cell "talk" to each other under drought conditions in the model plant Arabidopsis thaliana, a relative of canola.
Inside every animal and plant cell there are a series of connected pathways, like the production lines of a factory. For it to work efficiently, each department must be able to communicate product shortages, adverse conditions or breakdowns. In cells, the production lines, or pathways, are regulated by chemical signals and inputs, which can come from many sources.
Scientists have proposed for a while that chemical signals must be sent by a particular "plant department", or organelle, to the nucleus - the cell's control centre - for plants to become aware of and adapt to harsh conditions.
"The chloroplast is the plant organelle that converts light into food. The nucleus directs assembly and function of the chloroplast and this requires cross-talk between the two", Dr Estavillo said.
Despite these signals being proposed, they have been greatly debated and the signalling mechanisms for "talk" remain unclear.
But now, research on a mutant variety of Arabidopsis has lead to the discovery of a signal to the nucleus which is important in the plant response to drought. This research was lead by Dr Gonzalo Estavillo and Prof. Barry Pogson at the Australian National University node of the ARC Centre for Excellence in Plant Energy Biology (Estavillo et al. (2011) The Plant Cell).
The Arabidopsis mutant plant lacked a protein called SAL1, which breaks down a small molecule further down the production line called "PAP". As the protein was absent, the production line was broken, so "PAP", which is usually found in the chloroplast, ended up building up in the nucleus. Surprisingly, this became a kind of drought alarm, telling the plant to save water. Consequently these mutant plants survived 50% longer in drought conditions.
More importantly, the researchers found that normal plants also accumulated PAP during drought conditions and that the PAP molecule was able to move between the chloroplast and the nucleus.
"We intend to fully investigate the potential of this remarkable PAP signal", says Dr Estavillo.
"It's a great time to be a plant scientist. We have the technology to decipher tiny and crucial molecular pathways in cells and use this knowledge to improve plant breeding and genetics. After all, plants are our food and fuel future."
Early Career Excellence: Putting the "Pro" in Proteomics
Professor Harvey Millar has been awarded the 2012 Fenner Medal by the Australian Academy of Science. This award recognises distinguished research in biology by a scientist under 40.
Professor Millar has built a remarkable career in the 14 years since he graduated from The Australian National University with a PhD in biochemistry. Now based at the University of Western Australia, he is a Chief Investigator for the ARC Centre of Excellence in Plant Energy Biology and Director of the new UWA Centre for Comparative Analysis of Biomolecular Networks.
Harvey 's passion is proteins and how they work. In the field of proteomics, scientists analyse the protein products made when genes are switched on and all the downstream modifications that make them work. This allows researchers to get meaningful information about how plants cope with changing environmental conditions and to find genes of interest for drought, flood, salinity or pest tolerance in plants. The proteomics laboratory he leads is ranked among the top 25 in the world.
Harvey's passion for science is apparent. "I vividly remember Harvey describing the molecular sciences to me as an Honours student in 2002," says Science Communications Officer Alice Trend. "He described us as modern explorers, finding out things no one has ever known before, seeing things that no one has ever seen. That will continue to have an impact on my interest in science for the rest of my life."
Still committed to this vision of discovery, Harvey's research group has recently uncovered a potential mechanism for rescuing wheat seedlings from flooding, a new role for free radical molecules in pathogen sensing, and are working to keep honeybees healthy to maintain pollination. Over the past decade his research has focused on respiration, energy production in cells, and its response to environmental stress.
"To have my research recognised in this way is exciting" said Prof Millar. "Finding out how plants work at a molecular level is of critical importance right now, in a world faced with dwindling resources and climate change. Research in biology is very much a team effort, so I want to acknowledge that any award recognises not just my efforts, but the work of many researchers in my laboratory over the past decade"
"We are very fortunate to have such an excellent scientist leading our young scientists, inspiring our students and working collaboratively on important Centre projects all over the world," commented Centre Director Prof Ian Small.
The Fenner Medal will be presented at The Shine Dome in Canberra on the morning of Thursday 3 May 2012.
She swam for love, she swam for glory
Dr Kate Howell recently took a quick diversion from plant science to cross the Dardanelles Strait, which connects Europe and Asia. Did she do this by boat? Or plane?
No, she swam.
Kate placed third female in the 5km inter-continental race across the Dardanelles in a field of 500. A delighted Kate explains the historical significance of the race.
"Greek legend recounts the story of lovers Leander and Hero. Leander used to swim across the Dardanelles every night to visit his lover guided by a lamp that she burned in her tower to mark the way. Legend has it that on the night of a storm the lamp blew out. Leander lost his bearings and drowned. Upon learning of her lover's tragic end, Hero then threw herself from her tower to her death. In 1810, the famous English poet, Lord Byron, inspired by Leander's feat ("And he swam for Love, as I for Glory") successfully swam across the Dardenelles strait. This accomplishment is often credited as the beginning of the modern sport of open water swimming."
After her salty sea voyage, Dr Howell continued to Croatia to attend the Plant Organellar Signaling conference, made possible through a travel grant she was awarded from the Federation of European Biochemical Societies. Her conference talk focussed on the characterisation of the "flv" mutant. This plant has a mutation in a PPR protein which results in a single base change in the nucleotide sequence of a subunit of the plastid-encoded RNA polymerase. This results in a striking phenotype (pictured bottom-right), due to delayed chloroplast biogenesis in the leaf margins.
Vacation and Honours Scholarships
Vacation Scholarships available now!
About to finish your science degree? Interested in undertaking an exciting PAID project over the summer break?
Applications for vacation scholarships at Plant Energy Biology are now invited from undergraduate students enrolled in a full-time science degree at the University of Western Australia and the University of Adelaide.
The Scholarship stipend is $250 per week tax free for 6 to 8 weeks. Applications must be received by 4pm on the last Friday in October, in any given year.
Application forms are available here.
Honours scholarships available now!
About to finish your science degree? Thinking of undertaking a year of scientific discovery at the University of Western Australia or the University of Adelaide?
Plant Energy Biology has several $6000 scholarships up for grabs to help get you through your Honours year in plant energy biology. Never before has plant energy biology been so important, as world energy resources dry up and our food supplies fail to match growing populations. There are many great projects which you can undertake in the Centre, which are outlined in the 2011 Honours Booklet
For more information, visit our Scholarships page.
CROP OF AWARDS FOR YOUNG PLANT RESEARCHERS
Recent PhD graduates of the ARC Centre for Excellence in Plant Energy Biology; Dr Reena Narsai, Dr Estelle Giraud and Dr Chris Carrie have all been awarded prizes for outstanding achievements as early career researchers.
These young investigators have been studying the secrets of plant energy biology, an area of increasing importance as world energy sources and food production lags behind population growth.
Reena, the winner of a UWA Young Investigator prize for High Achieving Young Investigators, combines wet lab experiments with complex bioinformatics analysis to study the factors that regulate how genes are expressed. Reena is particularly interested in the gene activation required for plant germination and growth, to gain deeper insight into how tiny seeds develop into seedlings. Understanding these processes could help in solving specific germination problems seen in crop species.
Estelle was the recipient of the UWA Outstanding Young Investigator award. She also combines the power of wet lab experiments with detailed bioinformatic analysis. Estelle works to identify mutations in plants that give rise to alterations in a plant's ability to sense and respond to environmental changes. This research provides an opportunity to select improved plant varieties for future crop improvement.
"Reena and I were both surprised and honoured to win UWA Young Investigator Awards recognising our research achievements," she said.
Dr Chris Carrie has been successful with a fast-tracked Humboldt Research Fellowship for Postdoctoral Research. Chris will travel to Munich next year to continue his important work studying dual targeting in plants. Dual targeting occurs when proteins that are manufactured in the one part of the cell travel to two organelles - such as the energy-producing mitochondria and chloroplasts - and has important implications for our understanding of how cells work.
Chris's comprehensive review of dual targeting, which was published in the Federation of European Biochemical Society (FEBS) Journal has also been recognized as one of the top 10 papers published in an October 2008 to March 2009 issue of FEBS journal.
"For all three researchers it is the complete body of work that has contributed to their award recognition. All three have produced several publications in high impact journals that have been cited extensively," remarked W/Prof James Whelan who works with the three early career investigators. "They have established enviable track records that will be the basis of outstanding careers."
UWA's Deep Sequencer
UWA LAUNCHES DNA DEEP SEQUENCER
Imagine capturing the entire human genome in a single day, for a few thousand dollars.
Now researchers at the University of Western Australia will be able to do just that, with the launch of its first Hi-Seq Illumina Deep Sequencer, the most powerful platform worldwide for next generation sequencing. In a single day of use, this new technology will allow researchers to obtain the sequence equivalent of the entire human genome project, which took 4 billion dollars and 10 years to complete over a decade ago.
To put that in perspective, it would take a person typing 60 words per minute, eight hours a day, around 50 years to type the 3 billion letters, or base pairs, that make up the human genome.
Deep sequencers provide powerful information by reading every base pair of DNA that makes up an organism, and sorting this data into meaningful genetic maps. Using this information, researchers are making incredible breakthroughs as they discover the genes responsible for diseases in plants and animals, find brand new species and map our evolutionary past.
"A genome sequence is the ultimate genetic map", says Professor Jim Whelan. "The availability of this technology opens up the sequencing field to ecologists, evolutionary biologists, environmental scientists and a variety of cellular and genetic disciplines. We are no longer tied to just studying model species like mice or the model plant Arabidopsis thaliana. It develops our potential to cheaply sequence individuals in a population, varieties, mutants or clones in a variety of organisms, and study how they respond to the environment under WA conditions. This will greatly increase our ability to fight disease and to breed a variety of crop species for desired traits, such as increased drought, heat, pest or salinity tolerance, thus allowing producers to respond to environmental change or disease in a rapid manner."
Plant Energy Biology 2011 Photo Competition Winners!
CIBER Photo Exhibition at Scitech
CIBER - PEB's affiliated honeybee research group have been working together with Scitech to put together a terrific photo exhibition, which is now showing at Scitech.
The exhibition showcases a range of captivating honeybee pictures, from close up images of workers in the hive to researchers catching drones in the field. You can view the Scitech event information here.
C4 Plants may hold secrets for crop yield improvement
C4 plants are particularly interesting as their photosynthetic rate is higher than C3 plants in hot climates. This is because the RuBisCO enzyme (Ribulose Bisphosphate Carboxylase/Oxygenase) within the central Bundle Sheath (BS) cells is turbocharged by the provision of CO2 from the surrounding Mesophyll (M) cells. The C4 cycle has evolved independently over 60 times (including in some native Australian species) and is found in some of the most productive crop species such as maize and sugarcane. Understanding how C4 plants arose from C3 ancestors would help in introducing this major trait into other crops such as rice and wheat, where it has potential to be harnessed for improving crop yields
Recently, Kaisa Kajala, a Post-Doctoral researcher working with Ian Small on the evolution of C4 plants won the Australian Society for Plant Scientists Poster Award for her poster at the Combined Biological Sciences Meeting (CBSM) (click to download poster pdf). Kaisa has also recently authored a review on how to engineer the C4 cycle into C3 species.
Kaisa explains some more about this fascinating photosynthetic spin off;
"I characterised the chloroplast transcriptomes of M and BS cells in our model C4 plant Cleome gynandra. Interestingly, the chloroplast transcriptomes of the two cell types had only minor differences, despite huge differences in accumulation of some proteins, such as RuBisCO. So it appears that these M and BS-specific protein accumulation patterns are regulated at the translational or post-translational level. This helps us better understand how the plant constructs its C4 machinery and improves our chances of transferring the system to other species"
Image: Foreground Cleome gynandra (C4),
background Cleome hassleriana (C3) in growth cabinet
Two Teaching Awards for Gonzalo Estavillo
An innovative and engaging research-led approach to teaching plant biology to undergraduates has resulted in two teaching awards for Dr Gonzalo Estavillo of the ARC Centre of Excellence in Plant Energy Biology at the Australian National University. In the "Plant Detectives" program students use investigative approaches to identify plant mutants in a real-world research setting. Dr Estavillo used his background and experience in Arabidopsis research to come up with his ideas for the practical part of the program.
The Plant Detectives teaching team, of which Dr Estavillo is a member, has been awarded a 2011 Australian Award for University Teaching: Citation for Outstanding Contributions to Student Learning by the Australian Teaching and Learning Council (ATLC).
In addition to this, Dr Estavillo is to be awarded the Australian Society of Plant Scientists (ASPS) Teaching Award for 2011. This award recognizes excellence, innovation and contributions to teaching plant science at an undergraduate level. The ASPS Teaching award will be conferred at the Combio 2011 Conference in Cairns in September. Congratulations Gonzalo!
Eureka Moment for Steve Smith
Eureka! Chief Investigator Steve Smith is one of 3 finalists in 2011 Annual Australian Museum Eureka Prize for Environmental Research. Steve was nominated by the University of Western Australia for his ongoing environmental research which is providing exciting new avenues for restoration ecology and understanding plant tolerance to stress. The Eureka Prizes are highly prestigious awards in Australia and reward excellence in the fields of scientific research and innovation, science leadership, school science, science journalism and science communication.
Plant Energy Biology heads to IBC
The latest crop of Plant Energy Biology researchers are joining the XVIII International Botanical Congress in Melbourne from the 23rd of July, 2011.
Among the crowd of Centre staff attending will be Director Ian Small and Chief Investigators Jim Whelan, Steve Smith and Barry Pogson. Our newest Chief Investigator Steve Tyerman of the University of Adelaide will also be in attendance.
Talks and posters from Centre staff will cover everything from the structural function of plant proteins, mitochondrial and chloroplast retrograde signalling, transcript profiles of C4 and nutrient starved plants, chloroplast development and the function of PPR proteins. Keep an eye out for talks from Kate Howell, Nic Taylor, Gonzo Estavillo and Chief Investigators on the conference website: http://www.ibc2011.com/
Image: Arabidopsis seedling by Rosemarie Farthing
A new Chief Investigator for the Centre
Plant Energy Biology is delighted to announce that Professor Steve Tyerman of the University of Adelaide is joining the Centre as a Chief Investigator. Professor Tyerman has researched nutrition, salinity and water relations in plants for some 25 years.
Steve's expertise will bring an increased focus to water and nutrient transport, whole plant physiology and an ability functionally characterise transporter genes that may be of interest.
"Steve is a highly respected plant scientist with a wealth of knowledge in water and nutrient transport," said Centre Director Ian Small. "We look forward to this collaboration, which brings together new knowledge, equipment and experts to address scientific questions of national interest."
About Professor Tyerman: In 2001 Steve obtained the Wine Industry Chair of Viticulture at the University of Adelaide, which has provided opportunities to apply his research to grapevine root physiology. He has received several awards for his plant physiology research and was elected as a Fellow of the Australian Academy of Science in 2003. He has won a prestigious Australian Research Council Professorial Fellowship to investigate the link between calcium transport and water transport in plants.
Lugg Medal for Jessica Hewitt
Plant Energy Biology is delighted to announce that Jessica Hewitt (pictured left, with Jenny Gillett on the right) has won The Lugg Medal at the University of Western Australia. The Lugg Medal is awarded to the student in the Bachelor of Science with Honours in Biochemistry who, in the opinion of the Board of Examiners in Life and Physical Sciences, is the best student in that course.
Jessica's Honours project focused on several proteins from the DYW class of pentatricopeptide repeat (PPR) proteins that have been identified as RNA editing factors in higher plants. PPR proteins are of great interest to Plant Energy Biology due to their ability to target and alter the RNA products of genes, therefore changing the way that a gene is expressed.
"The aim of my honours project was to investigate the hypothesis that the DYW domains in these these proteins actually catalyse the editing reactions. The project turned out to be challenging, so I was surprised and excited to receive the Lugg Medal and Award! It seems my efforts to solubilise these notoriously difficult proteins were not wasted," said Jessica.
Since finishing honours, Jess has entered the WA Department of Health Graduate Development Program. We wish this talented young lady the best with her future endeavours.
Amino acids give wheat better chance of surviving floods
What do liver cells have in common with wheat seedlings? The University of Western Australia's PhD student Rachel Shingaki-Wells has found that both cope with oxygen starvation better when fed three amino acids: glycine, serine and alanine.
The research has been published in the leading international plant journal Plant Physiology, and is leading to better understanding of how to maintain the seedling health of wheat when floods become a threat.
- Full UWA Press Release: click here
- Plant Physiology (Abstract and full text): click here
- Listen to an interview of Chief Investigator Harvey Millar on ABC Rural click here.
Respiratory reactive oxygen species influence plant defense against pathogens
Researchers from Plant Energy Biology in collaboration with scientists at CSIRO Plant Industry have made a discovery that will change the way scientists look at the role of respiration in regulating plant responses to disease. Every minute as we breathe our bodies make "reactive oxygen species", which are toxic oxygen-based chemicals. Our bodies have inbuilt defence systems which rapidly degrade these chemicals using antioxidant vitamins, therefore preventing cell damage which can lead to cancer and aging. But our research has found that in plants, while reactive oxygen species are also produced during respiration, they play a positive role in plant defence if properly controlled.
The research, which was co-funded by CSIRO, the Australian Research Council and the Grains Research and Development Corporation, was published this week in Proceedings of the National Academy of Sciences USA (Gleason et al 2011, June 13).
The research, led by Winthrop Professor Karam Singh (CSIRO and UWA) and Winthrop Professor Harvey Millar (UWA), focused on a respiration gene in the mitochondria, which is essential for energy production in plants, yeast and animals. In humans, a mutation in this gene leads to a range of neurological disorders.
Remarkably, the research found that plants with a mutation in this gene grew normally in good conditions, but under pathogen attack, could not form the reactive oxygen chemicals required to properly activate plant defence against fungal and bacterial pathogens.
We show that chemicals commonly considered to be 'bad' can sometimes be 'very good', said co-first author Dr Shaobai Huang from Plant Energy Biology. Despite their potential for damage, without the ability to generate these toxic chemicals from the mitochondria, plants are unable to coordinate an attack response.
- Abstract: click here
- Full Text (PDF): click here
The smoke detector gene
Management fire in SW Australian woodlands.
Photo: Ben Miller
Bushfires are an ever-present threat worldwide with potentially devastating consequences. In a fascinating twist from nature, however, the deadly smoke from bushfires also stimulates new life and vigorous plant growth with the following rains.
Previous work by chemists at UWA established the growth-stimulant in smoke to be a chemical called "karrikin" (Flematti et al, 2004).
Now for the first time, researchers in PEB have teamed up with these chemists to discover a gene which allows dormant seeds to sense and respond to karrikin. The icing on the cake, however, was the fact that this gene, called MAX2, also proved crucial to strigolactone signalling, an important plant growth hormone with a highly similar chemical structure.
Read more about lead researcher Dr David Nelson's "eureka moment" that lead to the publication in Proceedings of the National Academy of Sciences of the United States of America here.
Four Generations of Plant Education
Four generations of PhD supervisors and their students reunited at the annual ARC Centre for Excellence in Plant Energy Biology (PEB) retreat in April. A long history of expertise has been passed down from supervisor to student and these professionals continue to work together to understand and get the best out of plants; our food and fuel future.
Professor David Day, the Deputy Vice Chancellor (Research) at Flinders University, supervised Chief Investigator Harvey Millar's PhD on plant mitochondrial respiration at ANU from 1993-1996. Some years later, Winthrop Professor Harvey Millar teamed up with Professor Day to supervise Research Assistant Professor Nicolas Taylor's PhD at UWA from 2000-2003, focussing on mitochondria's role in plant response to environmental variation.
Nic explained "David's wealth of knowledge continues to be awe-inspiring. When I'm designing "new" experiments, often he'll remind me to look at a paper from before I was born, and often the answer was already there!"
Nic and Harvey have now teamed up to supervise Richard Jacoby's current PhD project as he investigates the molecular mechanisms of salinity tolerance in Australian wheat varieties.
I'm the beneficiary of a tremendous amount of accumulated knowledge. On a weekly basis I will use mitochondrial isolation procedures optimised by David in the 1980's in France, protein gel techniques optimised by Harvey at Oxford in the late 90's, and mass spectrometry techniques optimised by Nic here at PEB", said Richard
Professor Day, previous Chair of the Biochemistry Department at UWA, commented that "If the relationship between supervisor and student is thought of as paternal or maternal, that makes me Richard's great grandfather." The training and knowledge being passed down the line is incredibly valuable and PEB hopes that the tradition continues far into the future.
Plant Energy Photo Exhibition at UWA Uni Club
Following the success of our photography exhibition at Scitech, the beautiful PEB photography display is now featuring at the UWA Uni Club. The photos explore the incredible survival tactics of plants, including a journey through a plant's world - from bushfires spanning hundreds of metres across, right down to cells and molecules spanning only micrometres. We showcase current techniques in molecular biology while focusing on the amazing processes happening inside plant cells.
These fantastic images have also been picked up online by Perth Now and ABC.
PLANT ENERGY BIOLOGY TEAMS TRIUMPH IN TRIATHLON
Researchers from the ARC Centre of Excellence in Plant Energy Biology at The University of Western Australia took first place in the women's category of the sprint event of this year's Nissan/BRW Corporate Triathlon.
Kate Howell, Cathie Colas des Francs-Small and Sandra Tanz won the women's event in the speedy time of 49 minutes, 53 seconds, with Kate recording the 10th fastest swim overall of 10 minutes and 19 seconds. Kate even lapped her colleague who started in an earlier wave.
More than 2,300 competitors took part in the triathlon, which involved a 400m swim, 10km bike ride and 4km run, held on the Perth foreshore last Sunday, March 13.
Another team from Plant Energy Biology also did well at dispelling the myth that scientists are not good at sport, by placing 9th in the mixed category.
Well done to all who took part!
Western Australia's Mysterious Underground Orchid Revealed
Rhizanthella gardneri is a cute, quirky and critically endangered orchid that lives all its life underground. It even blooms underground, making it virtually unique amongst plants. Last year, using radioactive tracers, scientists at The University of Western Australia showed that the orchid gets all its nutrients by parasitising fungi associated with the roots of broom bush, a woody shrub of the WA outback. Now, with less than 50 individuals left in the wild, Plant Energy Biology scientists have made a timely and remarkable discovery about its genome.
Read our story in:
and
Link to the UWA media release
Publication:
Sota Fujii Awarded:
Plant Energy Biology Research Associate Dr Sota Fujii is off to a terrific start in 2011. Following on from his recent publication (Full Text) in the Proceedings of the National Academy of Sciences (PNAS), he has won both a Japanese research award and a fellowship to continue his valuable work in plant genetics.
Dr Fujii was selected from 300 agricultural scientists for the position of "Super Postdoctoral Fellow" by the Japan Society for the Promotion of Science (JSPS). The fellowship is funded by the Japanese Ministry of Education, Science, Sports and Culture.
I will do my best to use this precious money from Japanese Taxpayers to contribute to the advancement of life science at global level, like my hero Dr. Barbara McClintock,
pledged Dr Fujii.Dr Fujii's research on restorer to fertility genes in plants has also earned him a Inoue Research Award for Young Scientists. This prize for early career scientists highlights the great work being done by this promising young researcher.
Kai Xun Chan and family during the graduation ceremony in December [click to expand image (2.3MB)]
TWO IN A ROW - TOP HONOURS PRIZE TO PEB STUDENT
Following on from Peter Crisp's success in 2009, Kai Xun Chan has won the College of Medicine, Biology and Environment Prize for the most outstanding honours thesis 2010.
This prize is sponsored by the India Australia Association and is awarded each year to the Australian National University student who achieved the most outstanding Honours result.
Kai Xun's honours thesis was titled: "Investigating PAP regulation and metabolism in Arabidopsis thaliana during drought."
The study is an excellent extension and application of Peter Crisp's honours research. Peter found a signalling molecule called PAP that coordinated a new line of communication between the chloroplast and the nucleus during plant stress response.
Kai Xun's application of this discovery was to study how plants
regulate the abundance of this molecular signal (PAP) during drought.
"For my Honours thesis, I investigated how key plant hormones such as
abscisic acid (ABA) control PAP production during drought" said Kai Xun." I also studied how
plant cells accumulate PAP. Intriguingly, I found that PAP production is
controlled by both ABA-dependent and ABA-independent pathways.
This challenges conventional theory that these two pathways are distinct,
and places PAP at the crossroads between different molecular highways
in the plant cell."
Words of wisdom can be found from this young student who is now working towards his PhD in the
Pogson lab: I attribute my success to self-belief and persistence when things go wrong,
humility when things go right, a large slice of good luck, and above all great
supervisors coupled with the fantastic resources of the centre
. Congratulations Kai Xun!
Center research papers recently recommended reading by the Faculty of 1000
- Arabidopsis has a cytosolic fumarase required for the massive allocation of photosynthate into fumaric acid and for rapid plant growth on high nitrogen.
- Regulation of carotenoid composition and shoot branching in Arabidopsis by a chromatin modifying histone methyltransferase, SDG8.
- Mitochondrial malate dehydrogenase lowers leaf respiration and alters photorespiration and plant growth in Arabidopsis.
PEB SCIENTIST DISCOVERS KEY TO PLANT VITAMIN C LEVELS
Promising young Perth researcher Tiago Tomaz has recently published the discovery that removing two proteins from plants can increase levels of Vitamin C and have large effects on plant growth. This surprising discovery arose from altering plant respiration - the way plants "breathe" and produce energy.
The ability to increase a plant's Vitamin C content -a natural antioxidant - has many implications for improving the current approach to dietary vitamin supplementation and the development of antioxidant-rich foods. This knowledge may also help us create plants better able to withstand environmental stressors associated with climate change.
To read more, visit Plant Physiology.
STUDY REVEALS HOW PLANTS SOLVE PROBLEMS
A new study by researchers at The University of Western Australia has provided a unique insight into how the same protein plays different roles in plant and animal cells.
The study, led by Winthrop Professor Jim Whelan, Chief Investigator at the ARC Centre of Excellence in Plant Energy Biology, has been published in The Journal of Biological Chemistry.
Professor Whelan said that the one billion years of evolution which separated plants from other organisms meant that different solutions had evolved to solving the same problem.
This discovery will give us clues to how we modify or select plants to make different amounts of mitochondria. Mitochondria are the cell's power producers. They convert energy into forms that are usable by the cell,
he said. As mitochondria play many important roles in plants, the ability to alter the number and activity or mitochondria can affect plant growth and yield.
The study investigated how a protein called Mia40, which is present in yeast, animal and plant cells, had distinctly different functions in plants.
In yeast and animal cells, Mia40 is an essential protein and mutations that affect its function are lethal or lead to severe disease,
Professor Whelan said.
"However, what we found was that in plants, it appears that this protein has different roles because it is present in more than one location in the cell. Although it plays a number of roles, its absence in plants does not have as severe consequences as it does in yeast and animals.
This study not only gives us a unique insight into how plants solve problems differently to animal cells, it can allow us to design drugs or chemical inhibitors that can be used to inhibit this pathway selectively in plants or animals. For example, a chemical blocking this pathway in animals can act as a selective pesticide as it would not be harmful to a plant.
As the causative agents of human (and animal) diseases like malaria (caused by Plasmodium falciparum) or sleeping sickness and leishmaniasis (caused by Trypanosomes), often utilise plant-like systems, this finding opens avenues to develop drugs to counter these disease causing organisms without harmful side effects."
- Media Reference:
- Winthrop Professor Jim Whelan: (+61 8)6488 1749
- Janine MacDonald (UWA Public Affairs): (+61 8)6488 5563
Plant Energy Biology Professors among world's most cited plant scientists
The publisher of the two leading international journals for the advancement of plant science - Plant Physiology and The Plant Cell - has identified its most highly cited and influential authors.
Publications between 2004 and 2008 were analysed by The American Society of Plant Biologists (ASPB), revealing 12 authors from Australasia who have been recognised as among the most highly cited plant scientists in the world. Three of the 12 authors from the Australasian region are based at the University of Western Australia. Professor Harvey Millar, Professor Steven Smith, and Professor Jim Whelan are Chief Investigators at the ARC Centre of Excellence in Plant Energy Biology.
Professor Millar's study of plant stress responses has contributed both knowledge and new techniques to the field of proteomics, especially in the study of plant mitochondria and subcellular localisation of proteins in plants.
Our work provides tools for people to determine where proteins reside in plant cells, which helps explain how cells function. As a result, these findings are often cited by scientists as evidence to back decisions made in their research plans.
Professor Steve Smith's major research interests include plant energy metabolism and plant responses to the environment. His contribution to these fields has included finding key roles for plant metabolism in plant growth and understanding responses of plants to environmental stresses.
Prof Jim Whelan's valuable research on RNA (ribonucleic acid copies of genes) and the characterisation of protein import in the context of organelle biogenesis has revealed that the synthesis of new proteins requires a complex set of control points, starting from the activation of genes and synthesis of messenger RNA's, and ending in the transport of proteins to their final destinations. Professor Whelan explained that we study these processes using functional genomics tools in plants and this work is often cited as it provides a foundation for researchers working in diverse fields within plant biology.
Both Professor Whelan and Millar are previous recipients of the prestigious Peter Goldacre Medal for plant sciences in Australia (1998 and 2003), winners of many highly competitive fellowships and Professor Millar has been awarded both the WA Premier's Prize for Early Career Achievement in Science (2003) and the Science Minister's Prize for Australian Life Scientist of the Year (2008). Among Professor Smith's awards is an Australian Research Council Federation Fellowship (2004).
Plant Energy Biology at the University of Western Australia conducts research to discover and characterise the molecular components and control mechanisms that drive energy metabolism in plant cells. Its work will underpin future advances in crop performance in the face of climate change.
To view the full list of highly cited plant scientists, please see the "recognising our authors" link on the Plant Physiology or The Plant Cell websites.
24.09.10
New mechanism for acclimation to stress discovered
Scientists from Plant Energy Biology have discovered a new molecular mechanism by which plants deal with stress. These findings have been published as the September 28 cover-page article by the American Association for the Advancement of Science (www.aaas.org) in their marquee journal, Science Signaling.
Lead researcher Winthrop Professor Steven Smith, of UWA's Centre of Excellence in Plant Energy Biology, said understanding how plants grow under stressful environmental conditions was vital for food, fuel and fibre production.
We found that when plants are stressed they respond by increasing their
sensitivity to a steroid growth hormone called brassinosteroid. This
provides a way for them to step up to the challenge of growth in harsh
conditions,
Professor Steve Smith said.
Our discovery - a great piece of scientific detective work - shows that a plant does not just succumb to whatever the weather serves up: it responds positively by putting energy into continued growth even under difficult circumstances. This finding opens a new door to find ways to identify or select plants that perform better in difficult conditions.
The research was carried out in collaboration with scientists at the Australian National University's node of Plant Energy Biology. Research Assistant Professor Che is now a visiting researcher in one of the world's top brassinosteroid research laboratories at the SALK Institute in San Diego, where he is taking the next step forward in this research.
- To read the UWA Media release please click here.
- To read the full research article online from Science Signaling click here.
- To download the research article in PDF format click here.
Publication details:
Che P, Bussell JD, Zhou W, Estavillo G, Pogson BJ and Smith SM (2010)
Signaling from the Endoplasmic Reticulum Activates Brassinosteroid Signaling
and Promotes Acclimation to Stress in Arabidopsis. Science Signaling,
publication date Sept 28.
Chris Cazzonelli wins Goldacre Award!
Plant Energy Biology is delighted to announce that Research Associate Dr Christopher Cazzonelli has won the prestigious Peter Goldacre Award for plant research in Australia. Many research leaders in the field of plant science have previously won this prize, including Chief Investigators at PEB. The award highlights both Chris's future potential and the success of his current research.
While growing up on his parent's crayfish farm in Far North Queensland, Chris was inspired by a neighbour who worked as a plant physiologist for CSIRO and fascinated Chris with stories about a rapidly emerging field of science, called molecular biology. Even as a young man, Chris recognised the potential of how understanding the molecular secrets of the cell would be likely to have a huge impact on our lives.
After completing his PhD in plant genetic engineering and molecular gene regulation at the University of Queensland, Chris won a highly competitive United States Department of Agriculture Postdoctoral Fellowship to work in the Agricultural Research Service in Texas, USA. There he investigated the molecular nature of gene activation, gene silencing and remote sensing of plant stress events. In 2006, he was recruited by PEB to work with Prof. Barry Pogson and determine what regulates the production of a group of important molecules called carotenoids.
Carotenoids are colourful yellow, orange and red pigments synthesised by plants. Carotenoids form a valuable part of the human diet. A good example of this is the β- carotene
humans get from vegetables like carrots, which is essential for vitamin A production. Lack of vitamin A can lead to blindness and other immune problems, which is a significant concern in developing countries. The Golden Rice Project, which increases the levels of β- carotene in rice, is a great example of a scientific program working to solve nutritional problems.
In plants, carotenoids are necessary for photosynthesis, photoprotection and the production of phytohormone "signalling" molecules. Signalling molecules form communication networks within the cell and allow the plant to respond to internal and external cues, such as changes required for development or adapting to environmental stress.
One of Chris's achievements was to identify a genetic regulator that perturbed the production of carotenoids in plants, particularly in the shoot meristem and flowering tissues, which are active sites of cell division, differentiation and epigenetic programming. The team also found that the correct carotenoid concentrations were required to control developmental processes, such as shoot branching in the model organism Arabidopsis. The publications that followed these discoveries, including a paper in Plant Cell - highlighted as recommended reading by the Faculty of 1000 - are credited as having started a new wave of research on carotenoid regulatory biology.
Due to the significant roles that carotenoids have been discovered to play in coordinating cellular regulation as well as plant architecture and their implications for human health, the future possibilities for this research are extremely exciting. Congratulations Chris!
Teaching Excellence Award - Gonzalo Estavillo
Gonzalo Estavillo
Plant Energy Biology Research Associate Gonzalo Estavillo and
colleagues have received the Australian National University's (ANU)
most prestigious teaching award from the Vice Chancellor for their exciting Plants: Genes to Environment
program.
The teaching team led by Dr Adrienne Nicotra developed a novel plant biology class based on a lecture component
and a Plant Detectives
practical, which Gonzalo played a major role in developing.
For me, the main inspiration for the development of the class curriculum was my research on
Arabidopsis at the Centre
, Gonzalo said. It provided me with a solid background
as well as easy access to a variety of Arabidopsis mutants, ideas and techniques.
I realized that all these elements could be used as powerful tools to teach undergraduate students the major concepts of plant biology.
The way this second year science course excels is in its
forward-thinking structure and teaching support for students. The ANU-based team developed a
plant detective
style investigation which, over the semester,
created an avenue for students to use the knowledge gained from lectures
and discussion groups earlier in the year in a real-world research setting.
Assisted by world class plant researchers, the students grew an "unknown" Arabidopsis single gene mutant line and then the student
used a set of tests to examine how that particular mutation affects plant growth and shape. Using their data and public on-line
resources they then tried to identify the unknown mutation responsible for changes in the plant function or appearance.
Students learned that a small change to a single plant gene can significantly affect the way the plant grows and looks.
The whole process simulates scientific process,
as students finish the course by presenting their results in a symposium and writing a report in the format of a paper for a relevant journal.
So how does this forward-thinking project simulate real-world science? Mutations occur naturally in every organism when a small change in DNA occurs, such as damage by UV light or an error when DNA is replicated as cells divide. Occasionally this mutation can end up being of great benefit to the organism if gives it an advantage in a particular environment. Isolation and analyses of mutants are used by plant scientists to understand the role of genes and, ultimately, find plants with advantageous traits, such as the exceptional tolerance to harsh conditions like drought or salinity in Australia. Once identified, these plants can be bred with conventional lines to increase their tolerance to stress.
The program has received excellent feedback,
including one student commenting that it had sparked
students to think differently, to try new things, and ultimately, think like a successful scientist.
A further proof to the success of this course is the significant yearly increase in student enrolments
and in the percentage of students going into Honours after taking the class.
EMBO Post-doctoral Fellowship
Kammel Hammani (foreground)
Ex-Centre PhD student Kamel Hammani has just been awarded a prestigious European Molecular Biology Organisation (EMBO) Postdoctoral Fellowship to work with Professor Alice Barkan at the University of Oregon. The aim of the EMBO scholarship is to provide young, promising researchers with exposure to exciting new research environments.
Kamel's work with Plant Energy Biology was under a joint agreement with the Université de Strasbourg, France (read about joint PhD's here: http://www.international.uwa.edu.au/staff/agreements/joint). The topic of his work was a particularly interesting group of proteins known as pentatricopeptide repeat proteins (PPR proteins).
Members of PEB have gone a long way to characterising the family of 450 PPR proteins in higher plants, which are believed to be able to bind to very specific sites on RNA. An understanding of how these proteins do this could open up considerable opportunities. The ability to selectively destroy RNA from a disease causing gene before it is translated into protein, for example, could revolutionise the way we approach medicine.
His future project in the US is a continuation of this work and is entitled Exploring the potential of pentatricopeptide repeat proteins for the site-directed modulation of RNA metabolism.
PEB wishes Kamel all the best with his research, thanks him for his valuable contribution and looks forward to collaborating with him in the future.
Update: A further congratulations go to Kamel as his recent paper in The Plant Cell, titled A Study of New Arabidopsis Chloroplast RNS Editing Mutants
Reveals General Features of Editing factors and Their target Sites
, has been awarded a special commendation
from the University of Western Australia.
FIVE SUPER SCIENCE FELLOWS FOR PLANT ENERGY BIOLOGY!
The ARC Centre for Excellence in Plant Energy Biology (PEB) will host five new "Super Science Fellows" under the Australian Government’s $27.2 million Super Science Fellowships scheme, aimed at attracting the world’s best early career researchers.
The University of Western Australia was awarded three fellowships in biotechnology. The fellows, who will be based at PEB, will investigate the interaction between rice plants and phosphate fertilisers. Crop plants require the addition of phosphate fertilisers in nutrient poor Australian soils. All types of phosphates are not equal, and it is estimated that billions of dollars worth of phosphate from previous fertiliser applications lie in our soils in forms unusable to plants. Due to the fact that phosphate deposits worldwide are dwindling, it is critical that we find out how to breed crop plants that use these limited supplies more efficiently.
This project will draw on many forms of expertise, including the rice genetics programme at Zhejiang University in China, to provide a clear first in phosphate efficiency research. The applications of this research could have immense value to crop production for decades to come.
A further two biotechnology fellowships, awarded to the Australian National University will focus on improving plant productivity and human health using advanced biotechnology approaches at the PEB node in Canberra.
Award Wining Thesis
Peter Crisp from Barry Pogson's lab at the Australian National University has been awarded the College of Medicine, Biology and Environment Prize for most outstanding honours thesis in 2009. The prize is sponsored by the India Australia Association and is awarded each year to the student who, in that year, achieved the most outstanding Honours result, as determined by the Dean of Science.
A word from Peter, explaining his research:
I have been investigating how individual cells co-ordinate a plant's response to stressful environments, in particular how different parts of a cell communicate. Because plants cannot get up and move when the sun gets too hot or when they run out of water, they have evolved clever ways of avoiding or adapting to stresses in their environment. Critical to a plant's survival is its ability to perceive environmental changes and co-ordinate emergency responses. The part of this process that I am interested in is how one part of the cell (for instance the chloroplast- where photosynthesis occurs) tells another part (for example the nucleus - where genetic information for the plant is stored) that the plant is in trouble. As it turns out plant-cell-communication involves a complex interplay of many different signals and signalling pathways. Although plant biologists have already uncovered a great deal about this type of "stress signalling" there remains a lot more that we don't know. Indeed one of the continuing great mysteries of plant biology is chloroplast-nucleus communication: we know that these parts of the cell must communicate yet despite a great deal of research we know very little about how they convey messages to each other. The aim of my research was to find ways in which the chloroplast and nucleus communicate. Together with my supervisor Gonzalo Estavillo and others in our research team I believe that we have uncovered a mechanism of chloroplast-nuclear communication, which revolves around an inconspicuous molecule called PAP.
Peter's thesis was entitled "PAP signals a new line of communication between the chloroplast and the nucleus" was an investigation of the molecular consequences of mutation of the Arabidopsis SAL1 gene. The thesis expounded a novel biochemical pathway involving the metabolite PAP and a class of exonuclease enzymes that appear to regulate a range of stress responses, for example high-light gene induction. Together with his supervisor Gonzalo Estavillo and fellow PhD student Nok Pornsiriwong, the "SAL1 research team" has found that this pathway is regulated from the chloroplast and hence represents a mechanism of retrograde signal transduction. Peter attributes his award to "hard work, a healthy dose of good fortune, fantastic supervisors and the terrific resources and opportunities that the centre has created". Peter is now working towards his PhD on the same topic in the Pogson lab.
Centre contributes to paper published in proceedings of the national academy of sciences
A chemical 'smoke signal' enables seeds and seedlings to better 'see' the light and to adapt their growth to the new conditions, according to researchers at The University of Western Australia.
A paper documenting the results of years of research by scientists in UWA's Faculty of Life and Physical Sciences in collaboration with Kings Park and Botanic Garden is published today in the prestigious Proceedings of the National Academy of Sciences in the USA.
The 'smoke signal', named 'karrikins', comprises the substances in bushfire smoke that stimulate germination of dormant seeds, and make some seeds and seedlings more responsive to light. The name derives from the Noongar word for smoke - karrik. In keeping with convention in naming families of biologically active molecules, the -in suffix was added to form 'karrikin'.
After a fire, the light quality is altered because it is no longer filtered by a canopy of leaves, and the soil is blackened. Karrikins make some seeds much more sensitive to this new light regime, so that they germinate more readily and produce sturdier seedlings. This discovery has major implications for understanding bush regeneration after fires and for using karrikins to help germinate valuable seeds, or to restore the vegetation at mine sites.
UWA plant biologist Dr David Nelson who discovered the response to light said:
"We found that seedlings exposed to karrikins become more responsive to light. They shorten their stem and expand their first leaves to produce a stockier seedling that is adapted to the exposed conditions left by fire."
Living organisms have learnt to use a range of chemicals to provide them with information about the surrounding environment," said UWA chemist, Professor Emilio Ghisalberti. "Karrikins provide plants with more information than we ever imagined.
We've found that plants are highly adapted to the post-fire environment so that they maximise the chances of seedling establishment," said Kings Park Director Professor Kingsley Dixon. "The name 'karrikins' recognises that the scientific discovery was made on Noongar land, and reflects the importance of fire and smoke to plant ecology and to Aboriginal culture.
Photograph courtesy of Ben Miller, Kings Park and Botanic Garden.
Media References:
- Winthrop Pofessor Steven Smith (+61 8) 6488 4403
- (UWA ARC Centre of Excellence in Plant Energy Biology and School of Biomedical and School of Biomedical, Biomolecular and Chemical Sciences)
- Sally-Ann Jones (UWA Public Affairs) (+61 8) 6488 7975 / (+61 4) 20 790 098
- UWA Media Release
CIBER research published in science magazine
Seminal fluid from one male can damage the sperm of other males in insect species where females mate with several males, according to international research carried out at The University of Western Australia and published in Science Magazine [19 March 2010, Vol. 327].
UWA QEII Fellow Dr Boris Baer said the paper provides the first evidence that it is seminal fluid - rather than sperm - that may harm other males' sperm in the female, until a substance in the female acts to prevent further destruction.
While the quality of human sperm continuously decreases in western societies, selection has maintained very high sperm viability in social insect males because the sperm is used for fertilisation long after the males' death, which occurs during or shortly after mating. "These social insects are amazingly efficient at keeping sperm alive but it is still too early to extrapolate the importance of our results for altering human fertility," Dr Baer said.
Dr Baer and colleagues at the University of Copenhagen studied the seminal fluid of two species of bees - the multiple-mating honeybee and the single-mating bumble bee - and three species of Panamanian leaf-cutting ants, of which two are multiple-mating.
They found that only the seminal fluid of the multiple-mating species appears to have the capacity to damage the sperm of competitors. In the single-mating bumblebees, the male inserts a 'plug' into the female once she is mated which seems to prevent her re-mating, so ejaculates from different males never get into contact with each other and have not evolved a system of sperm warfare.
"The queens of ants and bees mate only during a brief period early in their lives, as young virgins, and store the sperm of their mates for the rest of their long lives in a single specialised organ, the spermatheca," Dr Baer said. "In some species such as leaf cutting ants, queens can initially store close to half a billion sperm and use them during several decades to sire a hundred million offspring."
Dr Baer said the current working models of the group can be illustrated by the 1872 painting by Jean-Leon Gerome, 'Pollice Verso' ('Thumbs Down') depicting a triumphant gladiator standing over the bodies of his enemies as wealthy women in the audience, who have given the losers the thumbs down, congratulate the victor.
"By analogy, the arena is the females' sexual tract, the gladiators are the ejaculates and the women have the power. Our current findings now provide first empirical support for this idea, and our current work at The University of Western Australia has started to identify those components within seminal fluid that are responsible for the effects as published in Science," he said.
Dr Baer is the coordinator of CIBER, the Collaborative Initiative for Bee Research. Located at UWA, CIBER aims to intensify basic scientific research into honeybee reproduction, immunity and ecology alongside with partners from the Australian bee industry. The ultimate goal is to better understand honeybees to avoid future dramatic losses of Australian honeybees as occurring elsewhere.
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