RESEARCH INTEREST

Regulation of root and shoot growth responses to drought.  Specific interests include: hormonal growth regulation, in particular the role of abscisic acid; mechanisms of cell wall loosening; osmotic adjustment.


RESEARCH

Our earlier work showed that in water-stressed maize primary roots, cell elongation is maintained preferentially towards the root apex, and that this ability involves an enhancement of cell wall extensibility. This helps the cells to maintain elongation despite reduced turgor pressure under water-limited conditions. We previously showed that this response is associated with increased activities of the cell wall-loosening proteins expansin and xyloglucan endotransglycosylase. Currently, we are conducting genomic and proteomic studies to develop a greater understanding of the genes, biochemical networks and cell wall proteins controlling root growth adaptation to drought conditions.  This work is part of a NSF Plant Genome Research Program grant involving scientists at the University of Missouri at Columbia, the Donald Danforth Plant Science Center in St. Louis, the University of Illinois at Urbana-Champaign, and Utah State University.


SELECTED PUBLICATIONS

Yamaguchi M, Sharp RE (2010) Complexity and coordination of root growth at low water potentials: recent advances from transcriptomic and proteomic analyses. Plant, Cell and Environment (in press) (special issue on Tolerance to Salt and Drought)

Yamaguchi M, Valliyodan B, Zhang J, LeNoble ME, Yu O, Rogers EE, Nguyen HT, Sharp RE (2010) Regulation of growth response to water stress in the soybean primary root. I. Proteomic analysis reveals region-specific regulation of phenylpropanoid metabolism and control of free iron in the elongation zone. Plant, Cell and Environment (in press)

Yamaguchi M, Valliyodan B, Zhang J, LeNoble ME, Yu O, Rogers EE, Nguyen HT, Sharp RE (2009) Regulation of growth response to water stress in the soybean primary root. I. Proteomic analysis reveals region-specific regulation of phenylpropanoid metabolism and control of free iron in the elongation zone. Plant, Cell and Environment (in press)

Yamaguchi M, Sharp RE (2009) Complexity and coordination of root growth at low water potentials: recent advances from transcriptomic and proteomic analyses. Plant, Cell and Environment (in press) (Special issue on Tolerance to Salt and Drought)