Genomic and proteomic analysis of Schizaphis graminum reveals cyclophilin proteins are involved in the transmission of cereal yellow dwarf virus.
Yellow dwarf viruses cause the most economically important virus diseases of cereal crops worldwide and are transmitted by aphid vectors. The identification of aphid genes and proteins mediating virus transmission is critical to develop agriculturally sustainable virus management practices and to understand viral strategies for circulative movement in all insect vectors. Two cyclophilin B proteins, S28 and S29, were identified previously in populations of Schizaphisgraminum that differed in their ability to transmit the RPV strain of Cereal yellow dwarf virus (CYDV-RPV). The presence of S29 was correlated with F2 genotypes that were efficient virus transmitters. The present study revealed the two proteins were isoforms, and a single amino acid change distinguished S28 and S29. The distribution of the two alleles was determined in 12 F2 genotypes segregating for CYDV-RPV transmission capacity and in 11 genetically independent, field-collected S. graminum biotypes. Transmission efficiency for CYDV-RPV was determined in all genotypes and biotypes. The S29 isoform was present in all genotypes or biotypes that efficiently transmit CYDV-RPV and more specifically in genotypes that efficiently transport virus across the hindgut. We confirmed a direct interaction between CYDV-RPV and both S28 and S29 using purified virus and bacterially expressed, his-tagged S28 and S29 proteins. Importantly, S29 failed to interact with a closely related virus that is transported across the aphid midgut. We tested for in vivo interactions using an aphid-virus co-immunoprecipitation strategy coupled with a bottom-up LC-MS/MS analysis using a Q Exactive mass spectrometer. This analysis enabled us to identify a third cyclophilin protein, cyclophilin A, interacting directly or in complex with purified CYDV-RPV. Taken together, these data provide evidence that both cyclophilin A and B interact with CYDV-RPV, and these interactions may be important but not sufficient to mediate virus transport from the hindgut lumen into the hemocoel.
USDA-ARS, Robert W. Holley Center for Agriculture and Health, Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, USA. ctamborindeguy@ag.tamu.edu
Cecilia
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Tamborindeguy
Michael S
MS
Bereman
Stacy
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DeBlasio
David
D
Igwe
Dawn M
DM
Smith
Frank
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White
Michael J
MJ
MacCoss
Stewart M
SM
Gray
Michelle
M
Cilia
D000595:Amino Acid Sequence; D000818:Animals; D001042:Aphids / Q000201:enzymology / Q000235:genetics* / Q000821:virology; D018554:Avena / Q000821:virology*; D021983:Cyclophilins / Q000235:genetics* / Q000378:metabolism; D018562:Disease Transmission, Infectious; D004199:Disease Vectors; D054884:Host-Pathogen Interactions; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D052679:Luteoviridae / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000821:virology*; D011485:Protein Binding; D040901:Proteomics; D011993:Recombinant Fusion Proteins
D019476:Insect Proteins; D007527:Isoenzymes; D011993:Recombinant Fusion Proteins; D021983:Cyclophilins