A role for the RabA4b effector protein PI-4Kβ1 in polarized expansion of root hair cells in Arabidopsis thaliana

被引：220

作者：

Preuss, ML

Schmitz, AJ

Thole, JM

Bonner, HKS

Otegui, MS

Nielsen, E ^{[1
]}

机构：

[1] Donald Danforth Plant Sci Ctr, St Louis, MO 63132 USA

[2] Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA

[3] Washington Univ, Dept Biol, St Louis, MO 63130 USA

[4] Univ Wisconsin, Dept Bot, Madison, WI 53706 USA

来源：

JOURNAL OF CELL BIOLOGY | 2006年 / 172卷 / 07期

关键词：

D O I：

10.1083/jcb.200508116

中图分类号：

Q2 [细胞生物学];

学科分类号：

071009 ; 090102 ;

摘要：

The RabA4b GTPase labels a novel, trans-Golgi network compartment displaying a developmentally regulated polar distribution in growing Arabidopsis thaliana root hair cells. GTP bound RabA4b selectively recruits the plant phosphatidylinositol 4-OH kinase, PI-4K beta 1, but not members of other PI-4K families. PI-4K beta 1 colocalizes with RabA4b on tip-localized membranes in growing root hairs, and mutant plants in which both the PI-4K beta 1 and -4K beta 2 genes are disrupted display aberrant root hair morphologies. PI-4K beta 1 interacts with RabA4b through a novel homology domain, specific to eukaryotic type III beta PI-4Ks, and PI-4K beta 1 also interacts with a Ca2+ sensor, AtCBL1, through its NH2 terminus. We propose that RabA4b recruitment of PI-4K beta 1 results in Ca2+-dependent generation of PI-4P on this compartment, providing a link between Ca2+ and PI-4,5P(2)-dependent signals during the polarized secretion of cell wall components in tip-growing root hair cells.

引用

页码：991 / 998

页数：8

共 42 条

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