Dr. Brandon Moore

Assistant Professor
Ph.D. Botany
1986, Washington State University

Research Interests
Plant Glucose and Calcium Signaling
Plant Biochemistry and Biotechnology

Office: 210 Biosystems Research Complex
Phone: (864) 656-6984
Email: moore8@clemson.edu

 

Research Activities

Signal transduction refers to processes by which cells receive information, interpret that information, and make appropriate responses to that information. While both plant and animal systems rely extensively on hormonal regulation of target gene expression, one emerging theme is that common nutrients such as sugars can profoundly affect organismal growth and development through both metabolic effects and signal transduction processes.

In plants, sugars regulate all aspects of growth by interacting with many different control processes, including ones with stem cell functions. For example, sugars can enhance meristematic cell division activity by stimulating production of nucleolin, a multi-function regulator of ribosome synthesis. The plant enzyme hexokinase1 is the best understood glucose signaling protein. Our isolation and characterization of a hexokinase1 mutant of Arabidopsis revealed associated phenotypes including reduced shoot and root growth, reduced leaf expansion, increased apical dominance, delayed flowering and senescence, altered hormone sensitivities, and changes in transcript levels of target genes. Complementation of these phenotypes by transformation of the mutant with a catalytically compromised hexokinase1 protein demonstrated that hexokinase1 is a moonlighting protein that integrates glucose metabolism with a separable signal transduction process.

The long-term objectives of our research are to understand the mechanisms and targets of hexokinase-dependent glucose signaling. We use molecular, biochemical, and cellular approaches to address both functional and evolutionary questions. For example, some of our recent studies have established that plants have novel hexokinase isoforms that lack catalytic activity, but which have regulatory functions in hormone signaling processes. Using a phylogenetic engineering approach, we also have been examining key amino acid residues for their role in enzyme catalysis or regulatory functions. At the cellular level, we have shown that hexokinase1 is bound to porin in the outer mitochondrial membrane. We hypothesize that the glucose sensor protein can affect target polysome recruitment by modulating the organization of ribosomes with the plant cytoskeleton.

In a more recent project, we are collaborating with Dr. Hong Luo to make transgenic cotton with value added traits. One approach is to overexpress a cotton Ca2+ sensor protein in order to develop germplasm with enhanced resistance to drought stress.

 

Recent Publications

Karve A, Rauh B, Xia X, Kandasamy M, Meagher RB, Sheen J, Moore BD (2008) Expression and evolutionary features of the hexokinase gene family in Arabidopsis. In review.

Balasubramanian R, Karve A, Moore BD (2008) A cellular framework for glucose signaling by Arabidopsis hexokinase1. Biosignaling, In press.

Balasubramanian R, Karve A, Kandasamy M, Meagher RB, Moore BD (2007) A role for F-actin in hexokinase-mediated glucose signaling. Plant Physiology 145:1423-1434.

Weston DJ, Bauerle WL, Swire-Clark GA, Moore BD, Baird V (2007) Characterization of Rubisco activase from thermally contrasting genotypes of Acer rubrum (Aceraceae). American Journal of Botany 94: 926-934.

Moore BD (2004) Bifunctional and moonlighting enzymes: lighting the way to regulatory control. Trends in Plant Science 9:221-228.

 

Additional Publication Resources