Mutations in the rotavirus spike protein VP4 reduce trypsin sensitivity but not viral spread.
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ABSTRACT:
SUBMITTER: Trask SD
PROVIDER: S-EPMC3709623 | biostudies-literature | 2013 Jun
REPOSITORIES: biostudies-literature
Publications
Mutations in the rotavirus spike protein VP4 reduce trypsin sensitivity but not viral spread.
Trask Shane D SD Wetzel J Denise JD Dermody Terence S TS Patton John T JT
The Journal of general virology 20130220 Pt 6
Infectious entry of the nonenveloped rotavirus virion requires proteolysis of the spike protein VP4 to mediate conformational changes associated with membrane penetration. We sequenced and characterized an isolate that was cultured in the absence of trypsin and found that it is more resistant to proteolysis than WT virus. A substitution mutation abrogates one of the defined trypsin-cleavage sites, suggesting that blocking proteolysis at this site reduces the overall kinetics of proteolysis. Kine ...[more]
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