Cloning and Sequence Analysis of the Chitinase Gene of Spodoptera litura Nuclear Polyhedrosis Virus

Using AcMNPV chiA-containing fragment as a probe, the chitinase gene of Spodoptera litura nuclear polyhedrosis virus (SpltNPV) was localized in two contiguous fragments, XbaI 5.1 kb and 2.1 kb, and the intact SpltNPV chiA gene was obtained by cloning and sequencing those two fragments. The complete open reading frame of the gene was 1 695 nucleotide long, encoding a putative protein of 564 amino acids with molecular weight of 62.9 kD. Sequence analysis further revealed that the 5' noncoding region had a baculovirus late promoter motif TAAG. A polyadenylation signal, AATAAA, was located dowmnstream of the translation stop codon. A putative signal peptide was present at the N-terminus of the protein. This gene shares 57% homology with AcMNPV chitinase gene.