| 摘要 |
NEW MATERIAL:The DNA coding the growth hormone polypeptide of fish and expressed by the formula. USE:Preparation of growth hormone polypeptide of fish. PREPARATION:For example, the frozen pituitary gland of chum salmon is solubilized by disintegrating in the presence of guanidium isothiocyanate, poured on a layer of cesium chloride solution, and subjected to the ultracentrifugation to recover the whole cytoplasm RNA as the precipitate. The RNA is dissolved in an NaCl solution and passed through a column of oligo(dT)cellulose. The mRNA separated by the above process is mixed with a vector primer prepared by incising a plasmid with a restriction enzyme, and treated with a reverse transcriptase to synthesize a DNA complementary to the mRNA. The DNA is cyclized by reacting with a linker DNA to obtain a recombinant DNA containing the DNA expressed by the formula. |
