title: APAF-1-ALT, a novel alternative splicing form of APAF-1, potentially causes impeded ability of undergoing DNA damage-induced apoptosis in the LNCaP human prostate cancer cell line.
abstract: We have found a novel alternative splicing product of the apoptotic protease activating factor 1 (APAF-1), termed APAF-1-ALT, in the LNCaP human prostate cancer cell line. APAF-1-ALT harbors the caspase recruitment domain and an incomplete CED-4 like/ATPase domain, but lacks the WD-40 repeat units. The LNCaP cell expressed the full-length APAF-1 weakly and APAF-1-ALT rather abundantly, especially after mycoplasma infection. LNCaP underwent a retarded DNA damage-induced apoptosis, which was independent of caspase 9 activity. APAF-1-ALT functioned less effectively in inducing apoptosis than did APAF-1-XL, the full-length APAF-1, in transient transfection. Moreover, APAF-1-ALT interfered with APAF-1-XL's ability to induce apoptosis in transient double transfection experiment. These results indicate that APAF-1-ALT is a molecule that is deficient and impeded for mediating apoptosis and that it may contribute to the resistance to DNA damage-induced treatment observed in LNCaP.
authors.affiliation: Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi 980-8575, Japan.
authors.forename: Takenori
authors.initials: T
authors.lastname: Ogawa
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Shiga
authors.forename: Sho
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Akira
authors.initials: A
authors.lastname: Horii
authors.forename: Toru
authors.initials: T
authors.lastname: Furukawa
mesh_terms: D000199:Actins / Q000378:metabolism; D017398:Alternative Splicing; D000818:Animals; D017209:Apoptosis; D053477:Apoptotic Protease-Activating Factor 1; D019556:COS Cells; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D003574:Cytochrome c Group / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004249:DNA Damage; D004996:Ethidium / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D009174:Mycoplasma / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000378:metabolism; D011485:Protein Binding; D014176:Protein Biosynthesis; D011506:Proteins / Q000737:chemistry* / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013347:Subcellular Fractions; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: C506592:APAF1 protein, human; D000199:Actins; D053477:Apoptotic Protease-Activating Factor 1; D003574:Cytochrome c Group; D011506:Proteins; C506433:CASP9 protein, human; D053453:Caspase 9; D020169:Caspases; D004996:Ethidium