Coronavirus JHM: nucleotide sequence of the mRNA that encodes nucleocapsid protein

Abstract

A DNA copy of the mRNA that encodes the nucleocapsid protein of Mouse Hepatitis Virus JHM has been cloned into pAT153. The DNA copy specifically inhibited the synthesis in vitro of the nucleocapsid protein. The cDNA was subcloned into M13 vectors and the entire sequence, 1767 bases including a 15 base terminal poly (A) tract, has been determined by chain-terminator sequencing. The sequence contained an open-reading frame that could encode a basic protein of mol.wt. 49700. From the predicted sequence it was apparent that the nucleocapsid protein has 5 basic regions, two of which are located near the middle of the sequence, a serine-rich region was also located, a feature which may be of functional importance as the nucleocapsid protein is phosphorylated at serine residues. The carboxy terminus of the nucleocapsid protein was found to be acidic. The 5' non-coding sequence contained a triple repeat of the pentamer AATCT, a structural feature which may play a significant role during the production of subgenomic viral mRNAs.