| 摘要 |
NEW MATERIAL:A polypeptide which is a functional unit of caldesmon and expressed by formula I [R is Ala-X (X is polypeptide residue expressed by formula II), H-X or H]. USE:A treating agent for cancer. PREPARATION:For example, the whole RNA is extracted from an avian germinal gizzard smooth muscle according to a conventional method and mRNA is then isolated by oligo(dT)cellulose column chromatography. The resultant mRNA is used as a template to prepare a cDNA with a reverse transpcriptase and construct a cDNA library. The obtained library is screened with Escherichia coli to select a clone containing a gene coding the polypeptide expressed by formula I. The obtained gene is separated, treated with a restriction enzyme and linked to a vector, etc., to prepare a recombinant plasmid, which is then introduced into a host and carry out transformation. The resultant transformant is subsequently cultured to afford the polypeptide expressed by formula I. |
