Journal of Molecular Medicine

, Volume 77, Issue 10, pp 695–698

Raf-like Ras/Rap-binding domains in RGS12- and still-life-like signalling proteins

  • Chris P. Ponting

DOI: 10.1007/s001099900054

Cite this article as:
Ponting, C. J Mol Med (1999) 77: 695. doi:10.1007/s001099900054


Ras proteins play critical roles in regulating cell growth and differentiation, and mutated Ras genes are expressed in a variety of human cancers. Consequently, much interest has centered on the binding partners of Ras, including the Ras-binding domain (RBD) of Raf kinase. Here evidence is presented that domains homologous to the Raf RBD are present in tandem in RGS12, RGS14 and LOCO, and singly in molecules similar to mouse Tiam-1. In addition, RGS12, RGS14 and LOCO are shown to contain single "LGN motifs" that are guanine nucleotide exchange factors specific for the α-subunit of G proteins. These findings indicate "cross-talk" interactions between signalling pathways involving Ras and Rap and pathways involving Rho, Rac and Gα GTPases.

Regulator of G protein signalling LGN motifs Giα GTPase Tiam-1 Signalling pathway

Copyright information

© Springer-Verlag 1999

Authors and Affiliations

  • Chris P. Ponting
    • 1
  1. 1.National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda MD 20814USA
  2. 2.Present address: C.P. Ponting, MRC Funtional Genetics Unit, Department of Human Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, e-mail: