Fig. 1.

The life cycle of coronavirus: At the beginning, S protein binds to the ACE2 receptor in host cells. Then, the conformation of S protein is changed and causes the virus envelope to merge with the cell membrane via the endosomal pathway. Next coronavirus releases its RNA into the host cell. Genome RNA is translated to viral replicas polyproteins pp1a and 1ab. That polyproteins disparted to small proteins by proteinases. Polymerase makes some of subgenomic mRNAs by discontinuous transcription and finally translated to viral proteins. Viral proteins and genome RNA are assembled to the ER and Golgi. After that, it transported via vesicles and released out of the cell. ACE2, angiotensin-converting enzyme 2; ER, endoplasmic reticulum; ERGIC, ER–Golgi intermediate compartment