RAB27A Human

The RAB27A protein is membrane-bound and cycles between active GTP-bound and inactive GDP-bound states. 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 . This protein plays a significant role in cytotoxic granule exocytosis in lymphocytes, which is essential for both granule maturation and granule docking and priming at the immunologic synapse .

RAB27A is involved in several important pathways, including MITF-M-dependent gene expression and the innate immune system . The gene is located on chromosome 15q21 and has several aliases, including GS2 and RAM . Mutations in RAB27A are associated with Griscelli syndrome type 2, a rare genetic disorder characterized by hypopigmentation and immunodeficiency .

Mutations in the RAB27A gene can lead to Griscelli syndrome type 2, which manifests as silvery-gray hair, light skin, and severe immune system deficiencies . This condition highlights the role of RAB27A in melanosome transport in melanocytes and cytotoxic killing activity in cytotoxic T lymphoblasts . In melanocytes, RAB27A binds to melanosomes, which are then transported along microtubules. The protein recruits Slac2A and myosin Va, essential for transferring melanosomes from microtubules to actin filaments .

Human recombinant RAB27A is used in various research applications to study its role in cellular processes and its involvement in diseases. Understanding the function and regulation of RAB27A can provide insights into potential therapeutic targets for conditions associated with its dysfunction.

For more detailed information, you can refer to the GeneCards entry on RAB27A and the MedlinePlus page on RAB27A.