title: Is the sigma2 receptor a histone binding protein?
abstract: Starting from the high affinity sigma(2) receptor ligand 2, (PB28), we synthesized amino derivative 4 and coupled it to an NHS-ester activated sepharose stationary phase column to elute a crude protein prepared by lysed human SK-N-SH neuroblastoma cells. We characterized the SDS-PAGE gel electrophoresis stained bands by MALDI-MS and LC-MS-MS analysis. The MASCOT MS-MS ion search program led to the identification of the protein components. The six eluted proteins had a molecular weight ranging from 13 kDa to 26 kDa and were human histone proteins. A human 40S ribosomal protein S3 (SwissProt accession number: P23396) was also identified as a comigrated band. The human histone proteins that were characterized were H3.3A histone (NCBI accession number: 51859376), H2B histone (NCBI accession number: 1568557), H2A.5 histone (NCBI accession number: 70686), H1 (NCBI accession number: 22770677), and H2.1 histone (SwissProt accession number: P16403). These results disclosed a dual hypothesis about the sigma(2) receptor, that is, that it is formed by histones or that the sigma(2) ligands also bind histone proteins.
authors.affiliation: Dipartimento Farmacochimico, Università degli Studi di Bari, via Orabona 4, 70125 Bari, Italy. colabufo@farmchim.uniba.it
authors.forename: Nicola Antonio
authors.initials: NA
authors.lastname: Colabufo
authors.forename: Francesco
authors.initials: F
authors.lastname: Berardi
authors.forename: Carmen
authors.initials: C
authors.lastname: Abate
authors.forename: Marialessandra
authors.initials: M
authors.lastname: Contino
authors.forename: Mauro
authors.initials: M
authors.lastname: Niso
authors.forename: Roberto
authors.initials: R
authors.lastname: Perrone
mesh_terms: D015057:1-Naphthylamine / Q000031:analogs & derivatives / Q000737:chemistry; D045744:Cell Line, Tumor; D002846:Chromatography, Affinity; D002853:Chromatography, Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D006657:Histones / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007202:Indicators and Reagents; D008024:Ligands; D013058:Mass Spectrometry; D009447:Neuroblastoma; D017480:Receptors, sigma / Q000737:chemistry / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000302:isolation & purification / Q000378:metabolism
chemical_list: C513155:8-(3-(4-cyclohexylpiperazin-1-yl)propyl)-4-methoxy-5,6,7,8-tetrahydronaphthalen-1-ylamine; D006657:Histones; D007202:Indicators and Reagents; D008024:Ligands; D017480:Receptors, sigma; D012269:Ribosomal Proteins; C106107:sigma-2 receptor; D015057:1-Naphthylamine