These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Human Parvovirus B19 nonstructural protein transactivates the p21/WAF1 through Sp1.
    Author: Nakashima A, Morita E, Saito S, Sugamura K.
    Journal: Virology; 2004 Nov 24; 329(2):493-504. PubMed ID: 15518826.
    Abstract:
    The expression of human Parvovirus B19 nonstructural protein 1 (NS1) induces cell cycle arrest at the G1 phase and is accompanied by increased expression of the cyclin-dependent kinase inhibitor, p21/WAF1. Here, we provide direct evidence that NS1 mediates the transactivation of p21/WAF1. Up-regulation of p21/WAF1 by wild-type NS1 but not an NS1 mutant deleted of its NTP binding motif was observed. We also demonstrated that the wild-type NS1 is unable to induce G1 arrest in p21-deficient cells. Using reporter plasmids containing various mutants of the p21/WAF1 promoter, luciferase assay further revealed that the binding sites of the promoter to the transcription factor Sp1 are critical for NS1-mediated transactivation. Indeed Sp1 interacts only with the wild-type NS1 but not the NS1 mutant. These results indicate a cooperative contribution of NS1 and Sp1 to the transactivation of p21/WAF1, which leads to G1 arrest.
    [Abstract] [Full Text] [Related] [New Search]