关键词: 猕猴桃, 脂氧合酶, LOX基因家族, EST, 克隆

Abstract: From Actinidia EST database, six LOX were cloned from kiwifruit flesh tissue, i.e. AdLox1-6. AdLox1, AdLox2, AdLox3 and AdLox4 contained full-length cDNAs with 2 739, 2 595, 2 739 and 2 709 bp, respectively, AdLox5 and AdLox6 were cDNA fragments of 1 359 and 1 557 bp. Among the six kiwifruit LOX genes, AdLox5 and AdLox6 had the highest amino acid sequence identity, which was 74%, while AdLox3 and AdLox5 produced the lowest amino acid sequence identity, which was 49%. Phylogenetic analysis showed that AdLox2, AdLox5 clustered as 92LOX, AdLox1, AdLox3, AdLox4 and AdLox6 clustered as 132LOX. There was a signal peptide sequence of 60 amino acids in allmembers of the 132LOX group, but no similar sequence in the 92LOX genes. AdLox1 was most similar to tomato TomLoxD at 80% identity at the amino acid level, AdLox2 and AdLox5 matched to TomLoxA with 68 and 75% identity, respectively, and AdLox4 and AdLox6 showed 62% and 63% sequence identity to TomLoxC, AdLox3 had less than 55% identity to LOX genes from tomato.

Key words: kiwifruit, lipoxygenase, LOX gene family, EST, cloning