Modulation of Cell Proliferation by Heterotrimeric G Protein in Arabidopsis

• DOI: 10.1126/science.1059040
• Publication Date: 2002-07-27T09:52:41Z
• Authors: Hemayet Ullah; Jin-Gui Chen; Jeff C. Young; Kyung-Hoan Im; Michael R. Sussman; Alan M. Jones
• Keywords: 0301 basic medicine; Indoleacetic Acids; Light; Arabidopsis Proteins; MAP Kinase Signaling System; Arabidopsis; Genes, Plant; Heterotrimeric GTP-Binding Proteins; GTP-Binding Protein alpha Subunits; Plant Leaves; 03 medical and health sciences; Phenotype; Genes, Reporter; Mutation; Morphogenesis; Intercellular Signaling Peptides and Proteins; Guanosine Triphosphate; 2,4-Dichlorophenoxyacetic Acid; Peptides; Alleles; Cell Size; Glucuronidase

The α subunit of a prototypical heterotrimeric GTP-binding protein (G protein), which is encoded by a single gene ( GPA1 ) in Arabidopsis , is a modulator of plant cell proliferation. gpa1 null mutants have reduced cell division in aerial tissues throughout development. Inducible overexpression of GPA1 in Arabidopsis confers inducible ectopic cell division. GPA1 overexpression in synchronized BY-2 cells causes premature advance of the nuclear cycle and the premature appearance of a division wall. Results from loss of function and ectopic expression and activation of GPA1 indicate that this subunit is a positive modulator of cell division in plants.