title: A 17-kD centromere protein (CENP-A) copurifies with nucleosome core particles and with histones.
abstract: We have detected and begun to characterize a 17-kD centromere-specific protein, CENP-A (Earnshaw, W. C., and N. Rothfield, 1985, Chromosoma., 91:313-321). Sera from several humans with CREST scleroderma autoimmune disease (CREST: calcinosis, Raynaud's phenomenon, esophageal dsymotility, sclerodactyly, and telangiectasia) bind this protein in immunoblot assays of HeLa whole cell or nuclear extracts. We have affinity purified the anti-17-kD centromere protein (anti-CENP-A) specific antibodies from immunoblots of HeLa nuclear protein. The antibodies react with epitopes present on CENP-A derived from humans but apparently do not recognize specific epitopes in either rat or chicken nuclei. Only human nuclear protein is CENP-A positive by immunoblot. Furthermore, human cells show localization of anti-CENP-A antibody to centromeres by immunofluorescence microscopy, whereas rat cells do not. On extraction from the nucleus, CENP-A copurifies with core histones and with nucleosome core particles. We conclude that this centromere-specific protein is a histone-like component of chromatin. The data suggest that CENP-A functions as a centromere-specific core histone.
mesh_terms: D000818:Animals; D001324:Autoantigens; D001327:Autoimmune Diseases / Q000097:blood; D000076247:Centromere Protein A; D002645:Chickens; D002868:Chromosomal Proteins, Non-Histone; D002877:Chromosomes, Human / Q000648:ultrastructure; D004912:Erythrocytes / Q000032:analysis; D006367:HeLa Cells / Q000166:cytology; D006657:Histones / Q000302:isolation & purification*; D006801:Humans; D008099:Liver / Q000032:analysis; D008970:Molecular Weight; D009698:Nucleoproteins / Q000302:isolation & purification*; D009707:Nucleosomes / Q000032:analysis / Q000648:ultrastructure*; D011485:Protein Binding; D051381:Rats; D012595:Scleroderma, Systemic / Q000097:blood
chemical_list: D001324:Autoantigens; C000619700:CENPA protein, human; D000076247:Centromere Protein A; D002868:Chromosomal Proteins, Non-Histone; D006657:Histones; D009698:Nucleoproteins; D009707:Nucleosomes