| Primary Identifier | IPR026091 | Type | Family |
| Short Name | HPS4 |
| description | Hermansky-Pudlak syndrome (HPS) is a disorder of organelle biogenesis in which oculocutaneous albinism, bleeding and pulmonary fibrosis result from defects of melanosomes, platelet dense granules and lysosomes []. HPS is common in Puerto Rico, where is mostly caused by mutations in the genes HPS1 or HPS3. Another HPS locus, HPS4 was identified by using mouse models []. It was suggested that HPS4 and HPS1 proteins may function in the same pathway of organelle biogenesis [].This family represents BLOC-3 complex member HPS4, a component of the BLOC-3 complex, a complex that acts as a guanine exchange factor (GEF) for RAB32 and RAB38, promotes the exchange of GDP to GTP, converting them from an inactive GDP-bound form into an active GTP-bound form. The BLOC-3 complex plays an important role in the control of melanin production and melanosome biogenesis and promotes the membrane localization of RAB32 and RAB38 []. |
