Location and Nucleotide Sequence of the Orgyia pseudotsugata Single Nucleocapsid Nuclear Polyhedrosis Virus Polyhedrin Gene

A restriction endonuclease map was determined for the Orgyia pseudotsugata single nucleocapsid nuclear polyhedrosis virus (SNPV) genome. The order of the fragments generated by the enzymes Bg/II, BamHI and XbaI was analysed using double digestion of the total genome and digestion of isolated restriction fragments. The location of the polyhedrin gene was then determined using a cloned polyhedrin gene from the O. pseudotsugata multiple nucleocapsid NPV (MNPV) as a hybridization probe. A fragment containing this gene was cloned, mapped, subcloned and the nucleotide sequence of a 1.3 kb fragment was determined which contained the entire polyhedrin reading frame and some flanking sequences. This gene demonstrated 76% nucleotide sequence homology and 87% amino acid sequence homology to the Autographa californica MNPV polyhedrin sequence. A probable regulatory element was identified which is common to the 5′ flanking region of all hypertranscribed late genes (polyhedrin and 10K proteins) which have been examined in baculoviruses.