Protein-protein interactions between Epstein-Barr virus nuclear antigen-LP and cellular gene products: Binding of 70-kilodalton heat shock proteins
Protein-protein interactions between Epstein-Barr virus nuclear antigen-LP and cellular gene products: Binding of 70-kilodalton heat shock proteins
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DOI:
10.1006/viro.1996.0289
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发表时间:
1996-06-01
期刊:
影响因子:
3.7
通讯作者:
Rowe, DT
中科院分区:
文献类型:
--
作者:
Kitay, MK;Rowe, DT
The EBNA-LP protein encoded by the open reading frame in the leader exons of the Epstein-Barr nuclear antigen messages is essential for efficient immortalization of a lymphocytes. Protein-protein interaction studies using affinity precipitation of proteins from [S-35]methionine-labeled cell lysates and bacterially expressed maltose binding protein EBNA-LP fusions were performed. A cellular 68/72-kDa doublet protein was detected. This banding pattern was shown to be identical to that obtained in affinity precipitations with fusions of glutathione-S-transferase and Sp1 (a basal transcription factor). For both EBNA-LP and Sp1 the specific interacting cellular proteins have been identified as heat shock proteins (HSP) 72/73. Affinity precipitation of HSP 72/73 with deletion mutants of EBNA-LP maps the interaction domain on EBNA-LP to exon Y2 which is required for immortalization. Immunoprecipitation of EBNA-LP from EBV-positive lymphoblastoid cell lines coprecipitated the HSP 72/73 proteins, indicating that the interaction occurs in vivo as well as in vitro. The association of HSPs with a widening range of nuclear proteins involved in gene expression and proliferation control now includes Sp1 and EBNA-LP and suggests that there is a central role for molecular chaperones in these processes. (C) 1996 Academic Press, Inc.