Abstract: In order to clarify the infection mechanism of Cucurbit chlorotic yellow virus(CCYV), we screened host factors interacting with P22. We used immunoprecipitation and mass spectrometry to screen 128 host factors in Nicotiana benthamiana interacting with P22. KEGG analysis showed that these genes were mainly involved in the pathways of carbohydrate metabolism, energy metabolism and signal transduction. The obtained 128 host factors could be divided into 39 functional groups by GO analysis, which belonged to three categories of biological process, molecular function and cell component. In the category of biological processes, photosynthesis, protein folding, glucose metabolic process and one-carbon metabolic process were the main functional groups. In the category of molecular function, ATP binding and metal ion binding were the main functional groups. And in the category of cell components integral component of membrane, cytoplasm and photosystem Ⅱ oxygen evolving complex were the main functional groups. Combined with the results of mass spectrometry, 8 candidate host proteins were selected according to the number of enriched peptide segments and protein function. KEGG database analysis showed that the metabolic pathways involved in the 8 candidate host proteins could be classified into three metabolic pathways:carbohydrate metabolism, energy metabolism and signal transfer. Yeast two-hybrid assay was used to verify the interaction between 8 host proteins and P22. The results showed that glyceraldehyde 3-phosphate dehydrogenase-A (GAPDH-A) interacted with P22 protein. P22 may affect the resistance of host and cause chlorosis and yellowing symptoms. Taken together we identified the host factors that interact with P22 and this study would lay the foundation for uncovering the mechanism of P22 protein in the CCYV infection.

Key words: Cucurbit chlorotic yellows virus, P22, Immunoprecipitation, Yeast two-hybrid assay

CLC Number: 

• S436.42