StAR Related Lipid Transfer Domain Containing Protein 5 (STARD5)

Upon sterol depletion, LXRs are inactive and SREBPs are cleaved, after which they bind promoter SREs and activate genes involved in cholesterol biosynthesis and uptake. Sterol transport is mediated by vesicles or by soluble protein carriers, such as steroidogenic acute regulatory protein (STAR). STAR is homologous to a family of proteins containing a 200- to 210-amino acid STAR-related lipid transfer (START) domain, including STARD5.The deduced 213-amino acid human STARD5 protein is 30% and 32% identical to STARD4 and STARD6, respectively, and consists entirely of a START domain. Northern blot analysis revealed ubiquitous expression of 3.0- and 1.5-kb transcripts, with highest levels in liver and kidney.