Disease relevance of WSMVgp1

• Mapping of the P1 proteinase cleavage site in the polyprotein of Wheat streak mosaic virus (genus Tritimovirus) [1].
• Monopartite members of the family Potyviridae utilize three virus-encoded proteinases to cleave the viral polyprotein into mature proteins [1].
• An alignment of potyvirus polyprotein sequences in the carboxy-terminal region of the P1 domain revealed WSMV P1 contained conserved H(257), D(267), S(303) and FIVXG(325-329) residues upstream of the cleavage site that are typical of serine proteinases and shown by others to be required for P1 proteolysis in Tobacco etch virus [1].

High impact information on WSMVgp1

• Inserts bearing the coding sequences of NPT II and beta-glucuronidase (GUS) were placed between the nuclear inclusion b (NIb) and coat protein (CP) domains of the wheat streak mosaic virus (WSMV) polyprotein ORF [2].
• The WSMV NIb-CP junction containing the nuclear inclusion a (NIa) protease cleavage site was duplicated, permitting excision of foreign protein domains from the viral polyprotein [2].
• Because the pathway of proteolytic maturation of the WSMV polyprotein has not been experimentally determined, random libraries of WSMV cDNA were made both in DNA-binding domain and activation domain plasmid vectors and introduced into yeast [3].
• A comparison of this sequence along with the 3' terminal 1315 nucleotides of SCSMV-AP determined earlier with the other members of the family Potyviridae indicated that it had only 30% identity at the amino acid level for the partial polyprotein open reading frame (ORF) with the members of Ipomovirus and Tritimovirus genera [4].

References