Nucleotide sequence of a rice genomic clone that encodes a class I endochitinase

Using a barley endochitinase cDNA as the probe, we screened a rice genomic library of Oryza sativa L. var. japonica that was constructed in EMBL3 and we isolated five endochitinase clones. The sequence of this endochitinase gene with its flanking regions is shown. This gene does not contain an intron and encodes a basic chitinase of length 318 amino acids with a putative 18 amino acid N-terminal signal peptide followed by a 43 amino acid cysteine-rich domain (containing 9 cysteine residues). The rice gene encodes a protein whose deduced amino acid sequence shares 69%, 70% and 78% identity with those of tobacco gene 55, bean and barley respectively.