Bst1 (Bone marrowstromal cell antigen1,ADP-ribosyl cyclase 2,CD157) is anenzyme that in humans is encoded by theBST1gene.[5][6][7] CD157 is aparalog ofCD38, both of which are located onchromosome 4 (4p15) in humans.[8]
Bst1 is a stromal cell line-derived glycosylphosphatidylinositol-anchored molecule that facilitates pre-B-cell growth. The deduced amino acid sequence exhibits 33% similarity with CD38. BST1 expression is enhanced in bone marrow stromal cell lines derived from patients with rheumatoid arthritis. The polyclonal B-cell abnormalities in rheumatoid arthritis may be, at least in part, attributed to BST1 overexpression in the stromal cell population.[7]
CD157 and CD38 are both members of the ADP-ribosyl cyclase family of enzymes thatcatalyze the formation ofnicotinamide andadenosine diphosphate ribose (ADPR) orcyclic ADP-ribose (cADPR) fromNAD+, although CD157 is a much weaker catalyst than CD38.[9][10][11] cADPR is required for regulation ofCa2+ in cells.[10] Only CD38 hydrolyzed cADPR to ADPR.[11] CD38 is widely expressed in tissues, whereas CD157 is primarily found in gut andlymphoid tissue.[11]
CD157 is highly expressed inacute myeloid leukemia, and is being evaluated as a diagnostic sign, as a treatment target, and as a means of monitoring treatment progress.[13]
BST1 andBST2 genes are unregulated by theNicotinamide (NAM) metabolism pathway.[14]
^abMalavasi F, Deaglio S, Funaro A, Ferrero E, Horenstein AL, Ortolan E, Vaisitti T, Aydin S (2008). "Evolution and function of the ADP ribosyl cyclase/CD38 gene family in physiology and pathology".Physiological Reviews.88 (3):841–886.doi:10.1152/physrev.00035.2007.PMID18626062.
Overview of all the structural information available in thePDB forUniProt:Q10588 (Human ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 2) at thePDBe-KB.
Ortolan E, Vacca P, Capobianco A, et al. (2003). "CD157, the Janus of CD38 but with a unique personality".Cell Biochem. Funct.20 (4):309–22.doi:10.1002/cbf.978.PMID12415565.S2CID23453325.
Kajimoto Y, Miyagawa J, Ishihara K, et al. (1996). "Pancreatic islet cells express BST-1, a CD38-like surface molecule having ADP-ribosyl cyclase activity".Biochem. Biophys. Res. Commun.219 (3):941–6.doi:10.1006/bbrc.1996.0327.PMID8645283.
Okuyama Y, Ishihara K, Kimura N, et al. (1997). "Human BST-1 expressed on myeloid cells functions as a receptor molecule".Biochem. Biophys. Res. Commun.228 (3):838–45.doi:10.1006/bbrc.1996.1741.PMID8941363.
Yamamoto-Katayama S, Ariyoshi M, Ishihara K, et al. (2002). "Crystallographic studies on human BST-1/CD157 with ADP-ribosyl cyclase and NAD glycohydrolase activities".J. Mol. Biol.316 (3):711–23.doi:10.1006/jmbi.2001.5386.PMID11866528.
