Involvement Of Atp Synthase Beta Subunit In Chikungunya Virus Entry Into Insect Cells

Chikungunya virus (CHIKV), the virus responsible for the disease chikungunya fever in humans, is transmitted by Aedes mosquitoes. While significant progress has been made in understanding the process by which CHIKV enters into mammalian cells, far less progress has been made in understanding the CHIKV entry process in insect cells. This study sought to identify mosquito-cell-expressed CHIKV-binding proteins through a combination of virus overlay protein binding assays (VOPBA) and mass spectroscopy. A 50-kDa CHIKV-binding protein was identified as the ATP synthase beta subunit (ATPS beta). Co-immunoprecipitation studies confirmed the interaction, and colocalization analysis showed cell-surface and intracellular co-localization between CHIKV and ATPS beta. Both antibody inhibition and siRNA-mediated downregulation experiments targeted to ATPS beta showed a significant reduction in viral entry and virus production. These results suggest that ATPS beta is a CHIKV-binding protein capable of mediating the entry of CHIKV into insect cells.