期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1992
卷号:89
期号:16
页码:7295-7299
DOI:10.1073/pnas.89.16.7295
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Full-length and truncated human BCL2 lacking the entire C-terminal hydrophobic domain have been overexpressed in Spodoptera frugiperda insect cells with the baculovirus expression system. Immunoblot analysis with BCL2-specific antibodies revealed that both full-length and truncated BCL2 are expressed as multiple immunoreactive species, suggesting posttranslational modifications. The expression of the full-length but not the truncated BCL2 extended the survival of baculovirus-infected cells by preventing virus-induced DNA cleavage. This result is consistent with the reported protective effect of BCL2 against apoptosis in mammalian lymphocytes and suggests a conserved function in evolution. Subcellular fractionation and indirect immunofluorescence studies in intact cells demonstrated that the recombinant full-length and truncated BCL2 proteins were expressed predominantly as nuclear membrane-associated proteins. These results imply that BCL2 must utilize hydrophobic domains other than the deleted domain for its association with the subcellular membranes. Metabolic labeling of insect cells expressing the full-length and the truncated form of BCL2 with 32P(i) demonstrated that BCL2 is a phosphoprotein.