Mutational and metal binding analysis of the endonuclease domain of the influenza virus polymerase PA subunit.

ABSTRACT: Influenza virus polymerase initiates the biosynthesis of its own mRNAs with capped 10- to 13-nucleotide fragments cleaved from cellular (pre-)mRNAs. Two activities are required for this cap-snatching activity: specific binding of the cap structure and an endonuclease activity. Recent work has shown that the cap-binding site is situated in the central part of the PB2 subunit and that the endonuclease activity is situated in the N-terminal domain of the PA subunit (PA-Nter). The influenza endonuclease is a member of the PD-(D/E)XK family of nucleases that use divalent metal ions for nucleic acid cleavage. Here we analyze the metal binding and endonuclease activities of eight PA-Nter single-point mutants. We show by calorimetry that the wild-type active site binds two Mn(2+) ions and has a 50

SUBMITTER: Crepin T 

PROVIDER: S-EPMC2937609 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature