Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2000 Nov 25;277(2):387-96.
doi: 10.1006/viro.2000.0615.

Mutations in domain V of the Sendai virus L polymerase protein uncouple transcription and replication and differentially affect replication in vitro and in vivo

Affiliations
Free article
Comparative Study

Mutations in domain V of the Sendai virus L polymerase protein uncouple transcription and replication and differentially affect replication in vitro and in vivo

C K Cortese et al. Virology. .
Free article

Abstract

The Sendai virus L and P proteins comprise the viral RNA-dependent RNA polymerase. The L subunit is thought to be responsible for all the catalytic activities necessary for viral RNA synthesis. Sequence alignment of the L proteins of negative-stranded RNA viruses revealed six regions of good conservation, domains I-VI, which are thought to correspond to functional domains of the protein. Domain V, amino acids 1129-1378, has no recognizable motifs, and to date its function is unknown. Site-directed mutagenesis was used to construct mutations across domain V. The mutant L proteins were all stably expressed and were tested for activity in several aspects of RNA synthesis. One set of mutants could synthesize more le+ RNA than mRNA, while two mutants showed the opposite phenotype, synthesizing more mRNA than le+ RNA. The majority of the mutants could synthesize mRNA, but not genome RNA in vitro, thus uncoupling transcription and replication. Several mutants could replicate in vivo, but not in vitro, at nearly wildtype L levels, suggesting the importance of the intact host cell for replication in some instances. One L mutant, SS24, was virtually inactive in all viral RNA synthesis. SS24 L was able to form a polymerase complex that recognized the nucleocapsid template, and thus these amino acids are essential for the initiation of RNA synthesis.

PubMed Disclaimer

Similar articles

Cited by

Publication types

LinkOut - more resources