PROSITE documentation PDOC51334

PRONE domain profile

In plants, the small GTP-binding proteins called Rops work as signalling switches that control growth, development and plant responses to various environmental stimuli. Rop proteins (Rho of plants, Rac-like and atRac in Arabidopsis thaliana) belong to the Rho family of Ras-related GTP-binding proteins that turn on signalling pathways by switching from a GDP-bound inactive to a GTP-bound active conformation. Activation depends on guanine nucleotide exchange factors (GEFs) that catalyze the otherwise slow GDP dissociation for subsequent GTP binding. The plant-specific RopGEFs represent a unique family of exchange factors that display no homology to any known RhoGEFs from animals and fungi. They comprise a highly conserved catalytic domain termed PRONE (plant-specific Rop nucleotide exchanger) with exclusive substrate specificity for members of the Rop family. The PRONE domain has been shown to be necessary and sufficient to promote nucleotide release from Rop [1,2,3].

The PRONE domain can be divided into three highly conserved subdomains separated by two short stretches of variable amino acid residues [1,2]. It is ~370 residues in length and displays an almost all α-helical structure except for a β-turn that protrudes from the main body of the molecule (see <PDB:2NTX>). The overall structure of the PRONE domain can be divided into two subdomains, the first one including helices α1-5 and α13, the second α6-12 [4].

The profile we developed covers the entire PRONE domain.