Targeting of promoters for trans activation by a carboxy-terminal domain of the NS-1 protein of the parvovirus minute virus of mice.
AUTOR(ES)
Legendre, D
RESUMO
The NS-1 gene of the parvovirus minute virus of mice (MVM) (prototype strain, MVMp) was fused in phase with the sequence coding for the DNA-binding domain of the bacterial LexA repressor. The resulting chimeric protein, LexNS-1, was tested for its transcriptional activity by using various target promoters in which multiple LexA operator sequences had been introduced. Under these conditions, NS-1 was shown to stimulate gene expression driven by the modified long terminal repeat promoters (from the retroviruses mouse mammary tumor virus and Rous sarcoma virus) and P38 promoter (from MVMp), indicating that the NS-1 protein is a potent transcriptional activator. It is noteworthy that in the absence of LexA operator-mediated targeting, the genuine mouse mammary tumor virus and Rous sarcoma virus promoters were inhibited by NS-1. Together these data strongly suggest that NS-1 contains an activating region able to induce promoters with which this protein interacts but also to repress transcription from nonrecognized promoters by a squelching mechanism similar to that described for other activators. Deletion mutant analysis led to the identification of an NS-1 domain that exhibited an activating potential comparable to that of the whole polypeptide when fused to the DNA-binding region of LexA. This domain is localized in the carboxy-terminal part of NS-1 and corresponds to one of the two regions previously found to be responsible for toxicity. These results argue for the involvement of the regulatory functions of NS-1 in the cytopathic effect of this parvovirus product.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=237260Documentos Relacionados
- Terminal regions of the NS-1 protein of the parvovirus minute virus of mice are involved in cytotoxicity and promoter trans inhibition.
- Generation and characterization of a temperature-sensitive mutation in the NS-1 gene of the autonomous parvovirus minute virus of mice.
- Functional Replacement of the Carboxy-Terminal Two-Thirds of the Influenza A Virus NS1 Protein with Short Heterologous Dimerization Domains
- The Epstein-Barr virus glycoprotein 110 carboxy-terminal tail domain is essential for lytic virus replication.
- Phosphorylation of the RNA Polymerase II Carboxy-Terminal Domain by the Bur1 Cyclin-Dependent Kinase