A Study on the Molecular Biology of Renin-Angiotensin System : Renin Gene Expression and Construction of Genomic Library

Renin-Angiotensin계의 분자생물학적 연구 : Renin유전자의 발현과 Genomic Library작성

Poly (A) + RNA was isolated from mouse submaxillary gland and renin mRNA was isolated by poly (U)-sepharose chromatography and sucrose linear densiW gradient centifugation. And renin mRNA was identified by in vitro translation and immunoprecipitation. In order to construct recombinant plasmid, renin cDNA was synthesized by using reverse transcriptase and inserted into EcoRi site of PUC19. In addition, the cDNA was also synthesized using polymerase chain reaction and inserted into HindlIl site of PUC19. The recombinant plasmid was transformed into JMlO3 and the expression of the inserted renin cDNA was examined. The transformant produced renin protein having a molecular weight of 45, 000 dolton, which showed hypertensive effect upon injecting it into rabbit ear vein. A renin genomic library was prepared by inserting rabbit kidney DNA into EMBL3 phage, and was screeined for the isolation of renin gemomic DNA using renin cDNA probe.

생쥐 악하선으로부터 분리한 전 RNA를 poly(U)-sepharose chromatography와 sucrose linear density gradient centrifugation 방법으로 레닌 mRNA를 분리하여 in vitro translation과 immunoprecipitation에 의하여 레닌 mRNA를 확인하였다. 레닌 mRNA로부터 레닌 cDNA를 합성하여 EcoRI inker를 이용하여 pUC19에 삽입시켰고, Taq, polymerase를 이용한 PCR방법으로 합성한 레닌 cDNA는 pUC19의 Hinalll 부의에 삽입하여 재조합 plamid를 각각 작성하였다. 이것을 JM103에 형질전환시켜 레닌 유전자 발현을 유도하여 45,000의 분자량을 갖는 레닌을 얻었으며 이 레닌 단백은 토끼으 혈압을 850115mmHg에서 115-140mmHg로 증가시키는 생리 활성을 나타냈다. 토끼의 신장 DNA를 EMBL3 phage에 삽입시켜 genomic library를 작성한 후, 레닌 cDNA로부터 합성한 probe로 plaque hybridization시켜 genomic 유전자를 갖는 재조합 phage를 분리하였다.