Dr Thomas Martin
Senior Lecturer
Biochemistry and Molecular Biology
University of Western Australia
Crawley , W.A. 6009
Australia
Email: tmartin@cyllene.uwa.edu.au
The big question
Plants face many environmental challenges such as nutrient availability, light conditions, abiotic and biotic stresses. These factors greatly influence resource allocation and thus plant productivity. Plants use manifold sensing, signalling and response mechanisms to achieve a fine balancing act in the face of these challenges. The regulatory mechanisms involved have to be co-ordinated with developmental programmes as well as cell and tissue specific requirements. Cross-talk of signalling mechanisms and sharing of signalling components suggests the general principle that signalling pathways operate as complex networks rather than isolated, independent cascades We are trying to identify and to understand these mechanisms in the quest to improve crop productivity in a sustainable fashion.
A class of plant proteins encoded by the so-called '14-3-3' gene family are considered key players in bringing various sensing, signalling and response pathways together. 14-3-3 proteins interact with and regulate the activity of key enzymes in plant nitrogen and carbohydrate metabolism. These interactions influence enzyme activity at critical steps in primary metabolism and thus alter plant resource allocation on a global scale.
The short-term goals
We have isolated a collection of T-DNA knock-out lines with single mutations in a number of 14-3-3 genes. Initially, we are studying the regulation of carbohydrate and nitrogen metabolism and the allocation of resources in these mutants under consideration of metabolic and developmental aspects. To achieve this, we are employing classical molecular, genetic and biochemical techniques in combination with metabolomics and functional genomics technologies. We are identifying specific 14-3-3 isoforms involved in defined regulatory processes such as for example the regulation of nitrate reductase.
Short-term goals:
- Identify specific 14-3-3 isoforms involved in the regulation of enzymes of carbohydrate and nitrogen metabolism
- Study the impact of 14-3-3 mutations on these metabolic pathways and the subsequent distribution and allocation of resources and storage compounds.
- Investigate the role of 14-3-3s in a developmental and environmental context.
| Group ( Laboratory) members and Areas of Research
|
|
- Dr Sylviane Comparot (Postdoctoral Researcher)
- Gavin Lingiah (Postgraduate student)
Currently active
- BBSRC Research Grant P15126 "Characterisation of T-DNA tagged 14-3-3 Arabidopsis mutants, 2001, £174,492
- BBSRC Studentship Grant 01/A1/P/07100 "Characterisation of 14-3-3 Arabidopsis mutants, 2001
Applications submitted or planned
- ARC Discovery project grant 'Regulation and co-ordination of carbohydrate and nitrogen metabolism by 14-3-3 proteins
| Techniques in the laboratory
|
|
- Arabidopsis molecular biology
- Reversed and molecular genetics
- Biochemistry of carbohydrate and nitrogen metabolism
- Metabolomics
- Small and large scale gene expression analysis
Top three areas of knowledge
- Carbohydrate and nitrogen metabolism
- Metabolic sensing and signalling
- Molecular genetics
Top three technical skills
- Molecular biology, reversed genetics and Arabidopsis mutant analysis
- Analysis of carbohydrate and nitrogen metabolism
- Expression analysis
| Publications - Last 5 Years
|
|
Comparot S, Lingiah G and Martin T (2003) Function and specificity of 14-3-3 proteins in the regulation of carbohydrate and nitrogen metabolism. J. Exp. Bot. 54: 595-604.
Martin T , Oswald O, Graham IA (2002) Arabidopsis seedling growth, storage lipid mobilization, and photosynthetic gene expression are regulated by carbon: nitrogen availability. Plant Physiol. 128: 472-481.
Stewart AJ, Chapman W, Jenkins GI, Graham I, Martin T , Crozier A (2001) The effect of nitrogen and phosphorus deficiency on flavonol accumulation in plant tissues. Plant Cell Environ. 24: 1189-1197.
Oswald O, Martin T , Dominy PJ, Graham IA (2001) Plastid redox state and sugars: Interactive regulators of nuclear-encoded photosynthetic gene expression. Proc. Natl. Acad. Sci. USA 98: 2047-2052.
Graham IA and Martin T (1999) Carbohydrate regulation of genes associated with photosynthesis, allocation and partitioning. In: Photosynthesis: Physiology and Metabolism. (R. Leegood, TD Sharkey and S. von Caemmerer, eds.). Kluwer Academic Publishers.
| Ten Career-Best Publications
|
|
Comparot S, Lingiah G and Martin T (2003) Function and specificity of 14-3-3 proteins in the regulation of carbohydrate and nitrogen metabolism. I nvited review, J. Exp. Bot. 54: 595-604.
Martin T , Oswald O, Graham IA (2002) Arabidopsis seedling growth, storage lipid mobilization, and photosynthetic gene expression are regulated by carbon: nitrogen availability. Plant Physiol. 128: 472-481.
Stewart AJ, Chapman W, Jenkins GI, Graham I, Martin T , Crozier A. (2001) The effect of nitrogen and phosphorus deficiency on flavonol accumulation in plant tissues. Plant, Cell Environ. 24: 1189-1197.
Oswald O, Martin T , Dominy PJ, Graham IA (2001) Plastid redox state and sugars: Interactive regulators of nuclear-encoded photosynthetic gene expression. Proc. Natl. Acad. Sci. USA 98: 2047-2052.
Graham IA and Martin T (1999) Carbohydrate regulation of genes associated with photosynthesis, allocation and partitioning. In: Photosynthesis: Physiology and Metabolism. (R. Leegood, TD Sharkey and S. von Caemmerer, eds.). Kluwer Academic Publishers.
Martin T , Hellmann H, Schmidt R, Willmitzer L and Frommer WB (1997) Identification of mutants in metabolically regulated gene expression. Plant J. 11: 53-62.
Martin T , Sotta B, Jullien M, Caboche M and Faure J-D (1997) ZEA3: A negative modulator of cytokinin responses in plant seedlings. Plant Physiol. 114: 1177-1185.
Frommer WB, Mielchen C and Martin T (1994) Metabolic control of a class I patatin promoter from potato in transgenic tobacco and tomato plants. Plant Physl. (Life Sci. Adv.) 13: 329-334.
Martin T , Frommer WB, Salanoubat M and Willmitzer L (1993) Expression of an Arabidopsis sucrose synthase gene indicates a role in metabolization of sucrose both during phloem loading and in sink organs. Plant J. 4: 367-377.
Schulz B, Banuett F, Dahl M, Schlesinger R, Schäfer W, Martin T ., Herskowitz I and Kahmann R (1990) The b alleles of U. maydis, whose combinations program pathogenic development, code for polypeptides containing a homeodomain-related motif. Cell 60: 295-306.
