Question

The haemagglutinin (H) spikes inserted into the envelope of influenza viruses are:

Select one:

a. non-glycosylated proteins synthesised as a single polypeptide from one of the 8 genome segments.

b. a trimer of polypeptides produced from a single gene product cleaved by proteolytic enzymes.

c. remarkably conserved antigenically as mutations causing single amino acid substitutions in the protein occur mainly in non-antigenic domains.

d. box-shaped structures on a slender stalk which cleave the linkage between the virus attachment protein and the cellular receptor allowing escape of the virus from the cell during the final stages of replication of the virus.

Answer 1

Enveloped viruses are use spike proteins as molecular mimics of the host molecules in order4 to bind to target celln receptor.like wise the hemaggulutinin also involves in this function.inserted into lipid membrane are spikes which are proteins that are actually comprised of glycoproteins because they consist of protein linked into sugars known as hemogglutinin  

option C is correct(remarkably conserved antigenically as mutations causing single amino acid substitutions in the protein occur mainly in non-antigenic domains.)