RASGRP1
RAS guanyl-releasing protein 1 is a protein that in humans is encoded by the RASGRP1 gene.
Function
RAS guanyl nucleotide-releasing protein (RASGRP) 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.
Gene
Alternatively spliced transcript variants encoding different isoforms have been identified. The corresponding rat gene rbc7, which lacks a 5-prime exon, represents a 5-prime and 3-prime truncated version of a larger normal rat transcript that encodes a predicted 90-kD protein. This shorter transcript has not been found in humans.
Clinical significance
Altered expression of the different isoforms of this protein may be a cause of susceptibility to systemic lupus erythematosus (SLE).