RRC ID 39620
著者 Ayukawa K, Taniguchi S, Masumoto J, Hashimoto S, Sarvotham H, Hara A, Aoyama T, Sagara J.
タイトル La autoantigen is cleaved in the COOH terminus and loses the nuclear localization signal during apoptosis.
ジャーナル J Biol Chem
Abstract La autoantigen is a 47-kDa nuclear protein that binds to nascent polymerase III transcripts and a number of viral RNAs. We show that La protein was cleaved to generate a 43-kDa fragment during apoptosis of human leukemic HL-60 cells treated with camptothecin or etoposide. Immunofluorescence microscopy showed that the La protein level was increased in the cytoplasm during apoptosis of HL-60 cells. In addition, UV irradiation of HeLa cells led to the cleavage and redistribution of La protein upon apoptosis. Several lines of evidence show that La protein is cleaved by caspase-3 or closely related proteases at Asp-374 in the COOH terminus. When the full-length (La) and COOH-terminally truncated (La delta C374) forms of La protein were expressed as fusion proteins with green fluorescence protein (GFP), GFP-La delta C374 was predominantly cytoplasmic, whereas GFP-La was localized in the nucleus. These results suggest that La protein loses the nuclear localization signal residing in the COOH terminus upon cleavage and is thus redistributed to the cytoplasm during apoptosis.
巻・号 275(44)
ページ 34465-70
公開日 2000-11-3
DOI 10.1074/jbc.M003673200
PII S0021-9258(20)88943-1
PMID 10913436
MeSH Animals Antibodies, Monoclonal / biosynthesis Apoptosis* Autoantibodies / biosynthesis Autoantigens / chemistry Autoantigens / immunology Autoantigens / metabolism* Base Sequence Cell Line DNA Primers Humans Hydrolysis Mice Nuclear Localization Signals* Ribonucleoproteins / chemistry Ribonucleoproteins / immunology Ribonucleoproteins / metabolism*
IF 4.238
引用数 69
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
ヒト・動物細胞 P3-X63-Ag8.653(RCB0146)