Cloning and sequencing of gene fragments of Paralichthys olivaceus arginase

A pair of primers was designed and synthesized according to the conservative nucleotide sequence （GenBank）of Scophthalmus maximus，Cyprinus carpio，Oncorhynchus mykiss，Danio rerio，et al. Total RNA from Paralichthys olivaceus was extracted by using TRIzol Reagent．With the designed primers，a gene fragment was obtained using RT-PCR method．The PCR products were purified and then cloned into pUcm-T vector followed by sequencing．The results showed that a 284 bp gene fragment was obtained. Contrasted with other species，the gene sequence obtained in this experiment showed 96％，85％，84％ and 82％ homology with S. maximus，C. carpio，D. rerio，O. mykiss，respectively. Through sequencing the gene fragment of Arg by bioinformatics technique，we found that Arg had no SignalP，no O-glycosylation sites，and no transmembrane （TM）region，but had a character structure of arginase. There was a center of β-sheet in the N-terminal N0.38-44，57-64，71-76，89-94. And the N-terminal No.7-18，50-52，81-87，may be the Alpha regions of Arg protein. The N-terminal No.37-45，74-77，were the predominant epitopes.