| Summary: | 碩士 === 國立成功大學 === 生物科技研究所碩博士班 === 92 === Grouper (Epinephelus spp.) is one of the major high economic aquaculture in Taiwan. Thus, if a gene product can be used of to short the breeding time of groupers and moreover can generate the equal or better quality of groupers than using the traditional breeding, then it will decrease their cost and increase the rate of reproduction. Myostatin is one of genes that can regulate skeletal muscle development and was found in groupers. The full length of myostatin cDNA found in mice and cattle, can cause increase of muscle mass by blocking or mutating this gene. Myostatin cDNA contains 1131 bps nucleotides (i.e. 367 amino acid residues) and myostatin is consist of three critical motifs which are N-terminal signal sequence of secretion、RXXR proteolytic processing site and C-terminal cysteine-rich region. The amino acid sequence of myostatin shows at least 70% conservation among organisms, especially in C-terminal cysteine-rich region which is identified as mature biological active region. Wittemore et al. (2003) developed a neutralizing monoclonal antibody to recognize the epitope of myostatin in mice, which is consisting of 15 amino acids within C-terminal portion of this protein and they found to block this epitope can increase double muscle in mice. But using this small peptide as an antigen may elicit immune response poorly, in order to increase immune response, we construct a gene contain a tandem repeat of this peptide by using TR-PCR technique and conjugated with domain I of pseudomonas exotoxin A. Comparing the muscle weight of groupers using six-copy myostatin epitope antigen with that groupers using one-copy myostatin epitope antigen and using the other two control antigens, PE(Ia) and PBS, we have found that the groupers immunized with the six-copy myostatin antigen has shown more muscle weight increase than others. Thus, inhibiting Myostatin in groupers can cause more muscle weight increase, so it can determine that the function of Myostatin in grouper might be the same function as in mammalian. Moreover, we can use this strategy like inhibiting Myostatin to cause more muscle weight increase and thus decrease fishermen’s cost and increase the rate of reproduction.
|
|---|
