PROBLEM TO BE SOLVED: To obtain the subject new polypeptide coded by Borna disease virus(BDV), having a specific amino acid sequence composed of a specific number of consecutive amino acrid subsequences, and useful for diagnosing BDV infectious diseases yielding both motional and behavioral disorders and for producing the vaccine for the diseases. SOLUTION: This new polypeptide, which is coded by Borna disease virus(BDV) and corresponds to the amino acid sequence of protein p57 or p9.5 having at least 10 consectutive amino acid sequences among those of the formula, etc., is useful for diagnosing the infection with BDV as a neurotropic virus inducing immune-mediated symptoms yielding both motional and behavioral disorders and for producing the vaccine for the diseases. This polypeptide is obtained by the following process: a RNA is isolated from rat brain infected with BDV by using e.g. acid guanidium isothiocyanate phenol-chloroform standard method and then subjected to RT-PCR using a primer consisting of the partial base sequence of a gene coding BDV-protein, and the resultant cDNA is expressed in host cells.
POLYPEPTIDE CORRESPONDING TO AMINO ACID SEQUENCE OF PROTEIN P57 OR 9.5 OF BORNA DISEASE VIRUS, NUCLEIC ACID FRAGMENT CODING THE POLYPEPTIDE AND THEIR USE INTENDED FOR DIAGNOSIS AND IMMUNIZATION