Original Paper

Physical Association between the EBV Protein EBNA-1 and P32/TAP/Hyaluronectin
Mei-Ru Chen^a, Jehng-Fen Yang^a, Chia-Wei Wu^a, Jaap M. Middeldorp^b, Jen-Yang Chen<sup>a

a</sup> Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan; and
^b Organon-Teknika, Boxtel, The Netherlands

Address of Corresponding Author

Journal of Biomedical Science 1998;5:173-179 (DOI: 10.1159/000025328)

  Key Words

• EBNA-1
• p32/TAP/hyaluronectin

  Abstract

Epstein-Barr virus (EBV) nuclear antigen-1 (EBNA-1) is a protein expressed constitutively during EBV latency. It is required to support the replication of the EBV genome once per cell cycle via the latent origin of replication, oriP. EBNA-1 also can activate transcription through binding to the family repeats of oriP. We wished to identify candidate cellular protein(s) that may interact with EBNA-1 and mediate these functions. A 32-kd protein was co-immunoprecipitated with EBNA-1 from 293 cells using a monoclonal antibody EBNA.OT1x. The regions of EBNA-1 which interact with this protein were studied using two deletion clones and mapped to EBNA-1 residues 1-102 and 325-357. Deletion of this region was shown previously in a mutant of EBNA-1 which had dominant-negative effects on both DNA replication and transactivation assays. The 32-kd protein was found to react with a polyclonal antiserum against P32/TAP (HIV Tat associated protein), which is known to interact with other RNA binding proteins and the RNA splicing factor SF2. The function of P32 was therefore proposed to involve RNA processing. In addition, this molecule was recently identified as hyaluronectin, which binds hyaluronic acid. Because several reports documented that intracellular hyaluronic acid can potentially affect cell proliferation, the association between EBNA-1 and P32/TAP/hyaluronectin may help the maintenance of episomal viral DNA within proliferating cells.

  Author Contacts

Mei-Ru Chen
Graduate Institute of Microbiology, No.1, Jen-Ai Rd. 1st Section
Taipei 100 (Taiwan)
Tel. +886 2 23970800 ext. 8298, Fax +886 2 23915180, E-Mail mrc@ha.mc.ntu.edu.tw

  Article Information

Received: Received: July 28, 1997
Accepted: November 11, 1997
Number of Print Pages : 7
Number of Figures : 4, Number of Tables : 0, Number of References : 32