ATP-binding cassette sub-family B member 9 is a protein that in humans is encoded by the ABCB9gene.[5][6]
The membrane-associated protein encoded by this gene is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the MDR/TAP subfamily. Members of the MDR/TAP subfamily are involved in multidrug resistance as well as antigen presentation. The function of this half-transporter has not yet been determined; however, this protein may play a role in lysosomes. Alternative splicing of this gene results in distinct isoforms which are likely to have different substrate specifications.[6]
Kobayashi A, Kasano M, Maeda T, et al. (2000). "A half-type ABC transporter TAPL is highly conserved between rodent and man, and the human gene is not responsive to interferon-gamma in contrast to TAP1 and TAP2". J. Biochem. 128 (4): 711–8. doi:10.1093/oxfordjournals.jbchem.a022805. PMID11011155.
Kobayashi A, Hori S, Suita N, Maeda M (2003). "Gene organization of human transporter associated with antigen processing-like (TAPL, ABCB9): analysis of alternative splicing variants and promoter activity". Biochem. Biophys. Res. Commun. 309 (4): 815–22. doi:10.1016/j.bbrc.2003.08.081. PMID13679046.
Homma K, Kikuno RF, Nagase T, et al. (2004). "Alternative splice variants encoding unstable protein domains exist in the human brain". J. Mol. Biol. 343 (5): 1207–20. doi:10.1016/j.jmb.2004.09.028. PMID15491607.
Ohashi-Kobayashi A, Ohashi K, Du WB, et al. (2006). "Examination of drug resistance activity of human TAP-like (ABCB9) expressed in yeast". Biochem. Biophys. Res. Commun. 343 (2): 597–601. doi:10.1016/j.bbrc.2006.03.002. PMID16554024.