Format

Send to

Choose Destination
J Virol. 2010 May;84(10):5391-403. doi: 10.1128/JVI.02221-09. Epub 2010 Mar 10.

Effect of ATP binding and hydrolysis on dynamics of canine parvovirus NS1.

Author information

1
Department of Biological and Environmental Science, University of Jyväskylä, Ambiotica B211.1, P.O. Box 35, FIN-40014 Jyväskylän Yliopisto, Finland.

Abstract

The replication protein NS1 is essential for genome replication and protein production in parvoviral infection. Many of its functions, including recognition and site-specific nicking of the viral genome, helicase activity, and transactivation of the viral capsid promoter, are dependent on ATP. An ATP-binding pocket resides in the middle of the modular NS1 protein in a superfamily 3 helicase domain. Here we have identified key ATP-binding amino acid residues in canine parvovirus (CPV) NS1 protein and mutated amino acids from the conserved A motif (K406), B motif (E444 and E445), and positively charged region (R508 and R510). All mutations prevented the formation of infectious viruses. When provided in trans, all except the R508A mutation reduced infectivity in a dominant-negative manner, possibly by hindering genome replication. These results suggest that the conserved R510 residue, but not R508, is the arginine finger sensory element of CPV NS1. Moreover, fluorescence recovery after photobleaching (FRAP), complemented by computer simulations, was used to assess the binding properties of mutated fluorescent fusion proteins. These experiments identified ATP-dependent and -independent binding modes for NS1 in living cells. Only the K406M mutant had a single binding site, which was concluded to indicate ATP-independent binding. Furthermore, our data suggest that DNA binding of NS1 is dependent on its ability to both bind and hydrolyze ATP.

PMID:
20219935
PMCID:
PMC2863850
DOI:
10.1128/JVI.02221-09
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center