Plant biology

RICs for Rop

Science's STKE  08 Jan 2002:
Vol. 2002, Issue 114, pp. tw15
DOI: 10.1126/stke.2002.114.tw15

Wu et al. used a genome-wide search to identify effectors for the guanosine triphosphatase (GTPase) Rop in Arabidopsis. They identified a new family of proteins with the Cdc42/Rac-interactive binding (CRIB) motif and studied the role of these proteins, called RICs for Rop-interactive CRIB motif containing proteins, in plants. The 11 RIC genes were divided into four groups on the basis of the sequence and structure of the predicted encoded proteins. Interactions with Rop were tested by using overexpression studies followed by phenotype and localization analysis. Not surprisingly, because of the highly variable primary sequences, the RICs appeared to interact differentially or not at all with Rop when coexpressed in tobacco pollen tubes. A direct interaction between Rop and several of the RICs was determined by yeast two-hybrid screening (the method used for the initial screen) and by glutathione S-transferase pull-down experiments. Thus, like the animal Cdc42 and the Rac GTPase family, the plant Rop GTPase appears to mediate signaling through interactions with proteins containing the CRIB domain.

G. Wu, Y. Gu, S. Li, Z. Yang, A genome-wide analysis of Arabidopsis Rop-interactive CRIB motif-containing protein that act as Rop GTPase targets. Plant Cell 13, 2841-2856 (2001). [Abstract] [Full Text]