Potential tumor suppressor. Seems to be involved in lymphocyte adhesion by linking RAP1A activation upon T-cell receptor or chemokine stimulation to integrin activation. Isoform 2 stimulates lymphocyte polarization and the patch-like distribution of ITGAL/LFA-1, resulting in an enhanced adhesion to ICAM1. Together with RAP1A may participate in regulation of microtubule growth. The association of isoform 2 with activated RAP1A is required for directional movement of endothelial cells during wound healing. May be involved in regulation of Ras apoptotic function. The RASSF5-STK4/MST1 complex may mediate HRAS and KRAS induced apoptosis.
