| 摘要 |
NEW MATERIAL:A guanosine-5-triphosphoric acid (GTP) binding protein having GTP binding activity and GTP hydrolyzing activity, containing an amino acid sequence having properties of the GTP binding activity inhibited by N- ethylmaleimide and expressed by the formula and being about 22K dalton in molecular weight. USE:An inhibitor of carcinogenesis by oncogene ras. PREPARATION:For example, G protein is separated from a crude membrane fraction extracted from a cow brain according to an ordinary method and the amino acid sequence is determined and DNA coding the sequence is synthesized and then the DNA is subjected to treatment by restriction enzyme to give DNA fragments, which are bounded to a vector to carry out cloning and a clone containing DNA coding GTP binding protein is selected and the selected DNA is bound to downstream a promoter of a vector for manifestation and the bound DNA is introduced into a host and the host is cultured to provide the GTP binding protein. |
