Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: April 12, 2013
Publication Date: May 15, 2013
Citation: Tatineni, S., French, R.C. 2013. Deletions in the coat protein cistron of wheat streak mosaic virus induced more severe symptoms than the wild-type virus. American Phytopathological Society Annual Meeting. 103:S2.143. Technical Abstract: Wheat streak mosaic virus (WSMV), an economically important virus in the Great Plains region, is the type member of Tritimovirus genus of the family Potyviridae. The role of coat protein (CP) in WSMV biology was examined by introducing a series of deletions covering SGSGS motifs (aa 36-40, 43-47 and 53-57), aa 58-100 and N- and C-terminal regions and their infectivity was tested on wheat. Deletion of SGSGS motifs either individually or all three motifs together elicited systemic symptoms similar to wild-type virus. However, deletions comprising downstream of SGSGS motifs, aa 58-84, 49-83 and 36-84 elicited more severe symptoms than wild-type virus with increased cell-to-cell movement and virus accumulation. In contrast, deletions comprising aa 85-100 with deletion of aa 85-100, 48-100 and 36-100 infected wheat at reduced levels with mild symptoms. CP with deletion of aa 6-27 at the N-terminal region, and 14 and 17 aa at the C-terminal region infected wheat systemically at reduced rates with mild to moderate symptoms. Deletions comprising aa 85-100 and aa 6-27 severely affected virion formation, while C-terminal 14 and 17 aa deletions did not, demonstrating that the C-terminal aa are required for cell-to-cell movement. These data suggest that CP of WSMV is able to tolerate extensive deletions without affecting virion assembly and systemic infection of wheat, which will facilitate expression and display of specialty epitopes/peptides embedded into virions.