M protein

Regular Articles Variation of the sequence in the gene encoding for transmembrane protein M of canine coronavirus (CCV)

Molecular and Cellular Probes
Volume 15, Issue 4, August 2001, Pages 229-233

A. Pratelli, V. Martella, G. Elia, N. Decaro, A. Aliberti, D. Buonavoglia, M. Tempesta and C. Buonavoglia

Abstract

A nucleotide variability in the sequence of the gene encoding for the transmembrane protein M of canine coronavirus (CCV) is described. A total of 177 faecal samples from pups with enteritis were analysed by a PCR and n-PCR specific for CCV. Four samples, collected from a dog presenting a long-duration shedding of CCV, and a sample from another diarrhoeic dog, were found positive by PCR but negative by n-PCR. Sequence analysis of the samples revealed silent nucleotide substitutions in the binding site of the internal primer used for the n-PCR. Moreover, the nucleotide substitutions occurring over the whole fragment of the five samples analysed were similar.

Keywords

canine coronavirus, M protein, variation

Unique N-linked glycosylation of murine coronavirus MHV-2 membrane protein at the conserved O-linked glycosylation site

Virus Research
Volume 66, Issue 2, February 2000, Pages 149-154

Yasuko K. Yamada, Mikiko Yabe, Takahiro Ohtsuki, Fumihiro Taguchi

Abstract

The membrane (M) proteins of murine coronavirus (MHV) strains have been reported to contain only O-linked oligosaccharides. The predicted O-glycosylation site consisting of four amino acid residues of Ser–Ser–Thr–Thr is located immediately adjacent to the initiator Met and is well conserved among MHV strains investigated so far. We analyzed the nucleotide sequence of a highly virulent strain MHV-2 M-coding region and demonstrated that MHV-2 had a unique amino acid, Asn, at position 2 at the conserved O-glycosylation site. We also demonstrated that this substitution added N-linked glycans to MHV-2 M protein resulting in increment of molecular mass of MHV-2 M protein compared with JHM strain having only O-linked glycans.

Keywords

Murine coronavirus, MHV, M protein, N-glycosylation, O-glycosylation