Macrophage scavenger receptor 1, also known asMSR1, is aprotein which in humans is encoded by theMSR1gene.[5][6] MSR1 has also been designatedCD204 (cluster of differentiation 204).
This gene encodes the class Amacrophagescavenger receptors, which include three different types (1, 2, 3) generated by alternative splicing of this gene. These receptors or isoforms are trimeric integral membraneglycoproteins and have been implicated in many macrophage-associated physiological and pathological processes including atherosclerosis,Alzheimer's disease, and host defense. They were thought to be expressed macrophage-specific, but recently shown to be present on different dendritic cells classes, too.[7]
The isoforms type 1 and type 2 are functional receptors and are able to mediate the endocytosis of modifiedlow density lipoproteins (LDLs). The isoform type 3 does not internalize modified LDL (acetyl-LDL) despite having the domain shown to mediate this function in the types 1 and 2 isoforms. It has an altered intracellular processing and is trapped within theendoplasmic reticulum, making it unable to performendocytosis. The isoform type 3 can inhibit the function of isoforms type 1 and type 2 when co-expressed, indicating a dominant negative effect and suggesting a mechanism for regulation of scavenger receptor activity in macrophages.[5]
Asaoka H, Matsumoto A, Itakura H, Kodama T (1993). "[Structural and function of the human macrophage scavenger receptor]".Nippon Rinsho.51 (6):1677–83.PMID8391600.
Teupser D, Thiery J, Seidel D (1999). "Alpha-tocopherol down-regulates scavenger receptor activity in macrophages".Atherosclerosis.144 (1):109–15.doi:10.1016/S0021-9150(99)00040-4.PMID10381284.
Nakamura T, Hinagata J, Tanaka T, et al. (2002). "HSP90, HSP70, and GAPDH directly interact with the cytoplasmic domain of macrophage scavenger receptors".Biochem. Biophys. Res. Commun.290 (2):858–64.Bibcode:2002BBRC..290..858N.doi:10.1006/bbrc.2001.6271.PMID11785981.
Tomokiyo R, Jinnouchi K, Honda M, et al. (2002). "Production, characterization, and interspecies reactivities of monoclonal antibodies against human class A macrophage scavenger receptors".Atherosclerosis.161 (1):123–32.doi:10.1016/S0021-9150(01)00624-4.PMID11882324.
Xu J, Zheng SL, Komiya A, et al. (2002). "Germline mutations and sequence variants of the macrophage scavenger receptor 1 gene are associated with prostate cancer risk".Nat. Genet.32 (2):321–5.doi:10.1038/ng994.PMID12244320.S2CID13499753.
Miller DC, Zheng SL, Dunn RL, et al. (2003). "Germ-line mutations of the macrophage scavenger receptor 1 gene: association with prostate cancer risk in African-American men".Cancer Res.63 (13):3486–9.PMID12839931.
Wang L, McDonnell SK, Cunningham JM, et al. (2003). "No association of germline alteration of MSR1 with prostate cancer risk".Nat. Genet.35 (2):128–9.doi:10.1038/ng1239.PMID12958598.S2CID30170866.
