RAS GTPases cycle between an inactive GDP-bound state and an active GTP-bound state. This gene encodes a calcium-regulated nucleotide exchange factor activating both RAS and RAS-related protein, RAC1, through the exchange of bound GDP for GTP, thereby, coordinating the signaling of distinct mitogen-activated protein kinase pathways. [provided by RefSeq, Oct 2011] see less RAS GTPases cycle between an inactive GDP-bound state and an active GTP-bound state. This gene encodes a calcium-regulated nucleotide exchange factor activating both RAS and RAS-related protein, RAC1, through the exchange of bound GDP for GTP, thereby, coordinating the signaling of distinct mitogen-activated protein kinase pathways. [provided by RefSeq, Oct 2011]