Maturation of Yellowfin Tuna(Thunnus Albacares)Ovaries from the Southern Waters of Taiwan

An”all-fish”transgene,pJAKY was constructed by which consisted of JAK1promoter and yellowfin porgy growth hormone(ypGH).Tilapia sperm which electroporated with pJAKY was used as plasmids carrier for gene transfer.These electroporated-sperm were immediately mixed with eggs and subsequently added withwater to stimulate fertilization.At day 181 since fertilization,14 presumptivetransgenic fishes remained alive.The genomic DNA from 13 fishes of them wereextracted from their pectoral and anal fins for PCR analysis.Presence of the integrated transgene within the genome was confirmed by that the expressed ypGHPCR fragments were positively detected from all examined genomic DNA samples.Further,one out of 14 transgenic fish was sacrificed to monitor the expression ofthe transgene at the transcriptional level by RT-PCR analysis.The expression ofypGH mRNA in the tissue of liver and brain was surely present and could bedirectly visualized on the agarose gel after electrophoresis.But the ypGH mRNAwas absent in the tissue of muscle and blood.During the rearing period after 14months,the average body weight of those 13 presumptive transgenic fishes wasscored by 1.73 folds weightier than that of non-transgenic fishes.Using mean ofbody weight as parameter for comparison,the group of transgenic fish grow fasterthan the group of non-transgenic fish around 4 months.