The GDP exchange factor AND-34 is expressed in B cells, associates with HEF1, and activates Cdc42.
AND-34, a novel GDP exchange factor, is expressed constitutively at significant levels in murine splenic B cells, but not in murine splenic T cells or thymocytes. In B cell lines, anti-IgM treatment up-regulates AND-34 transcript levels. B cell AND-34 associates with both the docking molecules p130Cas and HEF1. AND-34 binds by its GDP exchange factor domain to the C terminus of HEF1, a region of HEF1 previously implicated in apoptotic, adhesion, and cell cycle-regulated signaling. Overexpression of AND-34 in murine B cell lines activates the Rho family GTPase Cdc42, but not Rac, Rho, RalA, or Rap1. Consistent with this, a subpopulation of AND-34 overexpressing B cells have long filamentous actin-containing cellular extensions. AND-34 overexpression augments both autophosphorylation and kinase activity of the Cdc42/Rac-responsive serine/threonine kinase PAK1. As previously reported for lymphoid cells transfected with constitutively active Cdc42, AND-34 overexpression inhibits SDF-1alpha-induced B cell polarization. These studies suggest that p130Cas and HEF1-associated AND-34 may regulate B cell adhesion and motility through a Cdc42-mediated signaling pathway.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to scicrunch, however this is not currently a free service.