Abstract: In order to develop an efficient method for recombinant flounder growth hormone (r-fGH) production,a cDNA fragment coding for the flounder growth hormone (fgh) was amplified by PCR. Then fgh gene was cloned into the integrative plasmid pAO815 under the control of a methanol-inducible promoter. Clones containing a single fgh insert were used to construct cassettes bearing 2 and 3 copies of fgh tandem. The constructed plasmid was then transformed into Pichia pastoris cell line GS115 by lithium chloride transformation method. The transformants were screened, cultured and induced by 0.5% methanol. By these steps, the recombinant flounder growth hormone gene is expressed in Pichia pastoris.

Key words: flounder, recombinant flunder growth hormone, Pichia pastoris, gene expression