title: Novel antibody to human BASP1 labels apoptotic cells post-caspase activation.
abstract: Apoptosis is associated with morphological changes, including membrane blebbing, cell shrinkage, and chromatin condensation. However, the molecular mechanisms of the dynamic changes in cellular components during apoptosis are largely unknown. Here we developed a new rat monoclonal antibody, 9B1, that specifically immunolabeled dying cells in tissues and in cell cultures. The 9B1 antibody labeled the cytoplasm of apoptotic cells in a caspase-dependent manner. We identified human brain abundant membrane attached signal protein 1 (hBASP1) as the 9B1 antigen using the liquid chromatography with tandem mass spectrometry (LC/MS/MS) method. hBASP1 was present in the nucleus of HeLa cells, but relocated from the nucleus to the cytoplasm after the caspase activation step of apoptosis. Immunostaining analysis revealed that 9B1 preferentially labeled this cytoplasmic form of hBASP1. Labeling by 9B1 to distinguish apoptotic changes could be a novel criterion for determining whether cells with activated caspases are fated for survival or death.
authors.affiliation: Department of Genetics, Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Shizue
authors.initials: S
authors.lastname: Ohsawa
authors.forename: Tomomi
authors.initials: T
authors.lastname: Watanabe
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Katada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishina
authors.forename: Masayuki
authors.initials: M
authors.lastname: Miura
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000941:Antigens / Q000032:analysis / Q000276:immunology; D017209:Apoptosis; D053148:Caspase 3 / Q000032:analysis / Q000378:metabolism*; D002467:Cell Nucleus / Q000737:chemistry; D002470:Cell Survival; D002853:Chromatography, Liquid; D003593:Cytoplasm / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000032:analysis*; D009419:Nerve Tissue Proteins / Q000032:analysis*; D051381:Rats; D012097:Repressor Proteins / Q000032:analysis*; D053719:Tandem Mass Spectrometry
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; C104089:BASP1 protein, human; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D012097:Repressor Proteins; D053148:Caspase 3