MECHANISM OF PROTEIN INVOLVEMENT IN CHIKUNGUNYA VIRUS INFECTION IN MACROPHAGES

Abstract

Chikungunya virus (CHIKV) is a mosquito-borne virus transmitted to humans by the bite of an infected Aedes mosquito. CHIKV is the causative agent for chikungunya fever which may cause chronic arthritis in some patients. CHIKV can replicate in various cell types, including epithelial cells, endothelial cells, fibroblasts, and immune cells such as monocytes and macrophages. Among immune cells, macrophages are susceptible to CHIKV infection and play a critical role in immune defense against invading viruses. Thus, this study aims to investigate the protein expression in mouse macrophage cell line (RAW264.7) following CHIKV infection using mass spectrometry (LC-MS/MS) technique. The results showed a total of 1,104 altered phosphoproteins in CHIKV-infected RAW264.7 cells compared to the mock control. One hundred thirty-nine phosphoproteins were significantly up-regulated phosphoproteins, whereas forty-four down-regulated phosphoproteins were observed following CHIKV infection. A STRING network analysis determined the protein interaction in both up-regulated and down-regulated phosphoproteins that are essential in biological processes. The analysis of protein-protein interactions revealed the presence of three major networks among the up-regulated phosphoproteins including the RNA metabolic process, immune system process, and response to the virus. The major network observed among the down-regulated phosphoproteins was macromolecule metabolic processes. Our findings indicate that CHIKV is capable of infecting and replicating in RAW264.7 mouse macrophage cell line and has a significant impact on the protein expression of these cells which alters several phosphoproteins in the host biological processes.