RasGEF domain

RasGEF domain

Structure of human H-Ras.[1]
Identifiers
Symbol RasGEF
Pfam PF00617
InterPro IPR001895
SMART RasGEF
PROSITE PDOC00594
SCOP 1bkd
SUPERFAMILY 1bkd
OPM protein 1xd4
CDD cd00155

RasGEF domain is domain found in a family of guanine nucleotide exchange factors for Ras-like small GTPases.

Ras proteins are membrane-associated molecular switches that bind GTP and GDP and slowly hydrolyze GTP to GDP.[2] The balance between the GTP bound (active) and GDP bound (inactive) states is regulated by the opposite action of proteins activating the GTPase activity and that of proteins which promote the loss of bound GDP and the uptake of fresh GTP.[3][4] The latter proteins are known as guanine-nucleotide dissociation stimulators (GDSs) (or also as guanine-nucleotide releasing (or exchange) factors (GRFs)). Proteins that act as GDS can be classified into at least two families, on the basis of sequence similarities, the CDC24 family (see IPR001331) and this CDC25 (RasGEF) family.

The size of the proteins of the CDC25 family range from 309 residues (LTE1) to 1596 residues (sos). The sequence similarity shared by all these proteins is limited to a region of about 250 amino acids generally located in their C-terminal section (currently the only exceptions are sos and ralGDS where this domain makes up the central part of the protein). This domain has been shown, in CDC25 an SCD25, to be essential for the activity of these proteins.

Human proteins containing this domain

KNDC1; PLCE1; RALGDS; RALGPS1; RALGPS2; RAPGEF1; RAPGEF2; RAPGEF3; RAPGEF4; RAPGEF5; RAPGEF6; RAPGEFL1; RASGEF1A; RASGEF1B; RASGEF1C; RASGRF1; RASGRF2; RASGRP1; RASGRP2; RASGRP3; RASGRP4; RGL1; RGL2; RGL3; RGL4/RGR; SOS1; SOS2;

References

  1. Boriack-Sjodin PA, Margarit SM, Bar-Sagi D, Kuriyan J (July 1998). "The structural basis of the activation of Ras by Sos". Nature 394 (6691): 337–43. doi:10.1038/28548. PMID 9690470.
  2. McCormick F, Bourne HR, Sanders DA (1991). "The GTPase superfamily: conserved structure and molecular mechanism". Nature 349 (6305): 117–127. doi:10.1038/349117a0. PMID 1898771.
  3. McCormick F, Boguski MS (1993). "Proteins regulating Ras and its relatives". Nature 366 (6456): 643–654. doi:10.1038/366643a0. PMID 8259209.
  4. Downward J (1992). "Ras regulation: putting back the GTP". Curr. Biol. 2 (6): 329–331. doi:10.1016/0960-9822(92)90897-J. PMID 15335949.

Further reading

This article incorporates text from the public domain Pfam and InterPro IPR001895