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Entry URI http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u15824136i
Entry name Gu Ying et al. 2005 Apr. J. Cell Biol. 169(1):127-38.
Title A Rho family GTPase controls actin dynamics and tip growth via two counteracting downstream pathways in pollen tubes.
Authors Dowd Peter|Fu Ying|Gilroy Simon|Gu Ying|Li Shundai|Vernoud Vanessa|Yang Zhenbiao
Abstract Tip growth in neuronal cells, plant cells, and fungal hyphae is known to require tip-localized Rho GTPase, calcium, and filamentous actin (F-actin), but how they interact with each other is unclear. The pollen tube is an exciting model to study spatiotemporal regulation of tip growth and F-actin dynamics. An Arabidopsis thaliana Rho family GTPase, ROP1, controls pollen tube growth by regulating apical F-actin dynamics. This paper shows that ROP1 activates two counteracting pathways involving the direct targets of tip-localized ROP1: RIC3 and RIC4. RIC4 promotes F-actin assembly, whereas RIC3 activates Ca(2+) signaling that leads to F-actin disassembly. Overproduction or depletion of either RIC4 or RIC3 causes tip growth defects that are rescued by overproduction or depletion of RIC3 or RIC4, respectively. Thus, ROP1 controls actin dynamics and tip growth through a check and balance between the two pathways. The dual and antagonistic roles of this GTPase may provide a unifying mechanism by which Rho modulates various processes dependent on actin dynamics in eukaryotic cells.
Pubmed ID 15824136
Journal The Journal of cell biology
Volume 169
Issue 1
Pages 127-38
Publication date 2005 Apr
Num of phenotype gene 0