UNC-73 Activates the Rac GTPase and Is Required for Cell and Growth Cone Migrations in C. elegans

نویسندگان

  • Robert Steven
  • Terrance J Kubiseski
  • Hong Zheng
  • Sarang Kulkarni
  • Jorge Mancillas
  • Alberto Ruiz Morales
  • Chris W.V Hogue
  • Tony Pawson
  • Joe Culotti
چکیده

unc-73 is required for cell migrations and axon guidance in C. elegans and encodes overlapping isoforms of 283 and 189 kDa that are closely related to the vertebrate Trio and Kalirin proteins, respectively. UNC-73A contains, in order, eight spectrin-like repeats, a Dbl/Pleckstrin homology (DH/PH) element, an SH3-like domain, a second DH/PH element, an immunoglobulin domain, and a fibronectin type III domain. UNC-73B terminates just downstream of the SH3-like domain. The first DH/PH element specifically activates the Rac GTPase in vitro and stimulates actin polymerization when expressed in Rat2 cells. Both functions are eliminated by introducing the S1216F mutation of unc-73(rh40) into this DH domain. Our results suggest that UNC-73 acts cell autonomously in a protein complex to regulate actin dynamics during cell and growth cone migrations.

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عنوان ژورنال:
  • Cell

دوره 92  شماره 

صفحات  -

تاریخ انتشار 1998