These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Influenza type B neuraminidase can replace the function of type A neuraminidase.
    Author: Ghate AA, Air GM.
    Journal: Virology; 1999 Nov 25; 264(2):265-77. PubMed ID: 10562491.
    Abstract:
    Influenza A and B viruses do not form reassortants with each other, presumably due to selection at either the RNA or protein level. Although differences in the promoter sequences of type A and B viruses have been studied, selection at the protein level has not been addressed. In this paper we describe experiments to determine whether differences in structure and/or function of the neuraminidase (NA) protein preclude formation of A/B NA reassortants. Influenza type A (N9) NA or B/Lee/40 NA expressed from plasmids can support multicycle growth of a NA-deficient type A virus (NWS-Mvi), indicating that their function in tissue culture is similar. To determine whether the type A or B NA supplied in trans can be incorporated into the virion of NWS-Mvi, the virus grown in NA-expressing cells was purified by sucrose gradient centrifugation. In each case there was a peak of NA activity coincident with the virus peak, indicating that some NA protein is packaged into the virion. The experiments suggest that, in spite of large sequence differences, the functions of the head, stalk, signal-anchor, and cytoplasmic domains of type A and B NAs are similar in tissue culture. Thus, lack of formation of A/B NA reassortant viruses is not due to restriction at the protein level.
    [Abstract] [Full Text] [Related] [New Search]