RAB27A gene

The RAB27A gene (RAB27A stands for: Ras-Related Protein Rab-27A), a member of the RAS oncogene family) is a protein-coding gene located on chromosome 15q21.3. Alternative splicing occurs at this locus, and four transcript variants encoding the same protein have been identified. An important paralog of this gene is RAB27B.

The protein encoded by the RAB27A gene belongs to the superfamily of small GTPases, the Rab protein family. The protein is membrane-bound and may be involved in protein transport and signal transduction mediated by small GTPases.

The encoded RAB27 protein is a small GTPase that switches between an active GTP-bound and an inactive GDP-bound state. In its active state, it binds to a variety of effector proteins to regulate the homeostasis of the late endocytic pathway, including endosomal positioning, maturation and secretion (Zhang J et al. 2019). Plays a role in the exocytosis of cytotoxic granules in lymphocytes. Required for granule maturation as well as for granule docking and priming at the immunological synapse.

1. Canna SW et al (2020) Pediatric hemophagocytic lymphohistiocytosis. Blood 135:1332-1343.
2. Zhang J et al. (2019) DENN domain-containing protein FAM45A regulates the homeostasis of late/multivesicular endosomes. Biochim Biophys Acta Mol Cell Res 1866:916-929.