Recombinant Human GRAM domain-containing protein 1B (GRAMD1B), Truncated

Uniprot Id

Q3KR37

Target Species

Human

Target Name

GRAMD1B

Target Full Name

Protein Aster-B

Target Function

Cholesterol transporter that mediates non-vesicular transport of cholesterol from the plasma membrane (PM) to the endoplasmic reticulum (ER). Contains unique domains for binding cholesterol and the PM, thereby serving as a molecular bridge for the transfer of cholesterol from the PM to the ER. Plays a crucial role in cholesterol homeostasis in the adrenal gland and has the unique ability to localize to the PM based on the level of membrane cholesterol. In lipid-poor conditions localizes to the ER membrane and in response to excess cholesterol in the PM is recruited to the endoplasmic reticulum-plasma membrane contact sites (EPCS) which is mediated by the GRAM domain. At the EPCS, the sterol-binding VASt/ASTER domain binds to the cholesterol in the PM and facilitates its transfer from the PM to ER.

Target Subcellular Location

Endoplasmic reticulum membrane; Single-pass membrane protein. Cell membrane; Single-pass membrane protein.

Target Synonyms

GRAMD1B; KIAA1201; UNQ3032/PRO9834; Protein Aster-B; GRAM domain-containing protein 1B