Nucleotide and deduced amino acid sequences of the nucleocapsid protein of the virulent A75/17-CDV strain of canine distemper virus
Abstract
Virus persistence is essential in the chronic inflammatory canine distemper virus (CDV)-induced demyelinating disease. In the case of CDV there is a close association between persistence and virulence. Virulent CDV isolated from dogs with distemper shows immediate persistence in primary dog brain cell cultures (DBCC) and in different cell lines. We have evidence that the nucleocapsid (NP) protein plays an important role in the development of persistence. The NP-protein, the most abundant structural virus protein, also influences virus assembly and has some regulatory functions in virus transcription and replication. In this study we compared the nucleotide and deduced amino acid sequence of a virulent CDV strain (A75/17-CDV) to a culture-attenuated non-virulent strain (OP-CDV). Viral RNA was extracted from DBCC infected with virulent CDV. Virulent CDV retains its in vivo properties, such as virulence and ability to cause demyelination, when propagated in these DBCC. The viral RNA was reverse transcribed and the resulting cDNA amplified by polymerase chain reaction for subsequent cloning. The nucleotide sequences of these clones were determined by the dideoxy chain termination method. The number of nucleotides and the putative N...Continue Reading