TY - JOUR
T1 - A Novel ROP/RAC Effector Links Cell Polarity, Root-Meristem Maintenance, and Vesicle Trafficking
AU - Lavy, Meirav
AU - Bloch, Daria
AU - Hazak, Ora
AU - Gutman, Itai
AU - Poraty, Limor
AU - Sorek, Nadav
AU - Sternberg, Hasana
AU - Yalovsky, Shaul
N1 - Funding Information:
We thank D. Szymanski for comments and the Arabidopsis Biological Resource Center, University of Ohio for mutant seeds. This research was supported by the Israel Science Foundation Charles Revson research fund (ISF 399/03) and the German-Israeli DIP program to S.Y. M.L. was a recipient of the Israel Ministry of Science Eshkol and The Manna Center for Plant Biosciences, Tel Aviv University fellowships.
PY - 2007/6/5
Y1 - 2007/6/5
N2 - ROP/RAC GTPases are master regulators of cell polarity in plants, implicated in the regulation of diverse signaling cascades including cytoskeleton organization, vesicle trafficking, and Ca2+ gradients [1-8]. The involvement of ROPs in differentiation processes is yet unknown. Here we show the identification of a novel ROP/RAC effector, designated interactor of constitutive active ROPs 1 (ICR1), that interacts with GTP-bound ROPs. ICR1 knockdown or silencing leads to cell deformation and loss of root stem-cell population. Ectopic expression of ICR1 phenocopies activated ROPs, inducing cell deformation of leaf-epidermis-pavement and root-hair cells [3, 5, 6, 9]. ICR1 is comprised of coiled-coil domains and forms complexes with itself and the exocyst vesicle-tethering complex subunit SEC3 [10-13]. The ICR1-SEC3 complexes can interact with ROPs in vivo. Plants overexpressing a ROP- and SEC3-noninteracting ICR1 mutant have a wild-type phenotype. Taken together, our results show that ICR1 is a scaffold-mediating formation of protein complexes that are required for cell polarity, linking ROP/RAC GTPases with vesicle trafficking and differentiation.
AB - ROP/RAC GTPases are master regulators of cell polarity in plants, implicated in the regulation of diverse signaling cascades including cytoskeleton organization, vesicle trafficking, and Ca2+ gradients [1-8]. The involvement of ROPs in differentiation processes is yet unknown. Here we show the identification of a novel ROP/RAC effector, designated interactor of constitutive active ROPs 1 (ICR1), that interacts with GTP-bound ROPs. ICR1 knockdown or silencing leads to cell deformation and loss of root stem-cell population. Ectopic expression of ICR1 phenocopies activated ROPs, inducing cell deformation of leaf-epidermis-pavement and root-hair cells [3, 5, 6, 9]. ICR1 is comprised of coiled-coil domains and forms complexes with itself and the exocyst vesicle-tethering complex subunit SEC3 [10-13]. The ICR1-SEC3 complexes can interact with ROPs in vivo. Plants overexpressing a ROP- and SEC3-noninteracting ICR1 mutant have a wild-type phenotype. Taken together, our results show that ICR1 is a scaffold-mediating formation of protein complexes that are required for cell polarity, linking ROP/RAC GTPases with vesicle trafficking and differentiation.
KW - CELLBIO
UR - https://www.scopus.com/pages/publications/34249662680
U2 - 10.1016/j.cub.2007.04.038
DO - 10.1016/j.cub.2007.04.038
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
C2 - 17493810
AN - SCOPUS:34249662680
SN - 0960-9822
VL - 17
SP - 947
EP - 952
JO - Current Biology
JF - Current Biology
IS - 11
ER -