该基因是一个具有ras超家族鸟嘌呤核苷酸交换因子（gef）结构域的基因家族的成员。它作为一种二酰甘油（DAG）调节的核苷酸交换因子，通过GTP结合GDP的交换，特异性地激活Ras它激活Erk/MAP激酶级联，调节T细胞和B细胞的发育、稳态和分化另外，还发现了编码不同亚型的剪接转录变体。该蛋白不同亚型的表达改变可能是系统性红斑狼疮（sle）易感性的原因之一。[由RefSeq提供，2008年7月]
This gene is a member of a family of genes characterized by the presence of a Ras superfamily guanine nucleotide exchange factor (GEF) domain. It functions as a diacylglycerol (DAG)-regulated nucleotide exchange factor specifically activating Ras through the exchange of bound GDP for GTP. It activates the Erk/MAP kinase cascade and regulates T-cells and B-cells development, homeostasis and differentiation. Alternatively spliced transcript variants encoding different isoforms have been identified. Altered expression of the different isoforms of this protein may be a cause of susceptibility to systemic lupus erythematosus (SLE). [provided by RefSeq, Jul 2008]