Structure and function of the Entamoeba histolytica Gal/GalNAc lectin.
Gal/GalNAc lectin is a novel multifunctional virulence factor of the human parasite Entamoeba histolytica. The native protein is a 260-kDa heterodimer consisting of a type 1 membrane protein disulfide bonded to a lipid-anchored protein. Each subunit has several isoforms that may form functionally different heterodimers, analogous to the integrin family of proteins. Recently a second 150-kDa Gal/GalNAc lectin has been identified in E. histolytica that associates with the 260-kDa lectin. The functions of the 260-kDa lectin have been characterized using specific monoclonal antibodies. This lectin plays roles in many of the critical aspects of this parasite's pathogenicity including adherence, cytolysis, invasion, resistance to lysis by complement, and also perhaps encystment. Current knowledge regarding both the structure and function of this unique multifunctional virulence factor are discussed.
Mann
Barbara J
BJ
Department of Internal Medicine and Microbiology, University of Virginia, Charlottesville 22908, USA.
D000116:Acetylgalactosamine / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000954:Antigens, Surface / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D050260:Carbohydrate Metabolism; D002448:Cell Adhesion / Q000502:physiology; D004748:Entamoeba histolytica / Q000737:chemistry* / Q000472:pathogenicity / Q000502:physiology; D018604:Epitope Mapping; D005690:Galactose / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D016023:Integrins / Q000235:genetics / Q000378:metabolism; D037102:Lectins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D016415:Sequence Alignment; D015398:Signal Transduction / Q000502:physiology
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D016023:Integrins; D037102:Lectins; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D015800:Protozoan Proteins; C052452:galactose inhibitable adherence protein, Entamoeba histolytica; D000116:Acetylgalactosamine; D005690:Galactose