The role of RHO kinase pathway in coronavirus infection

Coronaviruses are known to cause respiratory tract infections, gastrointestinal tract infections, and systemic disease in humans, other mammals, and birds. Furthermore, they are responsible for common colds of humans. Coronaviruses became important for human health during the severe acute respiratory syndrome (SARS) outbreaks of 2002-2003 and caused hundreds of deaths. Moreover, novel coronaviruses also identified after SARS epidemic and they are still risk factor for human health. Rho signaling pathway plays essential role in regulating various cellular process such as cytoskeletal dynamics, vesicular traffic, morphogenesis, cell cycle progress, cell division, migration, adhesion and differentiation. Several studies have showed that Rho kinase pathway plays crucial role in viral infections, well documented with herpes viruses. Viruses modulate the Rho signaling pathway and as a result cause deregulation of cytoskeletal dynamics. The present study was aimed to examine the role of Rho signaling pathway in Coronavirus infection. In this study, HeLa-CEACAM cell lines transfected with expression plasmid pMHVR and MHV-A59 mouse hepatitis coronavirus were used as a model for coronaviral infection. mRNA expression levels of 32 genes that are known to have a role in Rho kinase pathway were examined by high-throughput, nanotechnology-based Fluidigm BioMark HD system Real-Time PCR. In this study we examined mRNA expression levels of Rho kinase pathway members. In this study surprisingly, expression levels of the most of the pathway members was not altered. However, the downregulation of RhoGDI? (4-fold) was found to be highly significant in six-hours infected cells compared to control group.