Function of the Arabidopsis Gene TORMOZ in Cell Division and Development

University Of California-Davis, Davis CA

Investigators

Abstract

0235548 Sundaresan The control of cell division is an important feature of development in multicellular organisms. In higher plants, both the timing and the plane of cell division are regulated and responsive to developmental cues. Although there are extensive studies showing that the cytoskeleton is important in executing the decision to divide in a predetermined plane, there is little information on the underlying molecular mechanisms. A mutation in Arabidopsis called tormoz (toz) has been identified, in which longitudinal divisions of the embryo are randomized. The mutant embryos arrest but can be rescued to generate seedlings which have severe morphological defects. The predicted TOZ gene product appears to have a close homolog in every sequenced eukaryote from yeast to humans. However, the function of the TOZ-related proteins has not been previously studied in any species. The role of the TOZ gene product in cell division and development in Arabidopsis will be investigated. First, the toz mutant seedlings will be used to examine how plant development has been affected by the mutation, including the extent to which patterning, and cell specification have been perturbed by the defect in cell division planes. Second, studies of toz mutant cells will be undertaken to determine possible functions of TOZ in the organization of the plant cytoskeleton for mitosis and cytokinesis. Third, the intracellular localization of the TOZ gene product during cell division in Arabidopsis will be studied to generate clues to the mechanism by which it may be involved in the control of division plane. Fourth, we will attempt to identify putative interacting partners of TOZ in order to gain further information on the molecular mechanism by which the TOZ protein executes its function. These studies will help to understand the control of cell division in plant development, and may add to the knowledge of cell division in animals and fungi. The project includes training of students and postdoctoral fellows and minority participation.