Prokaryotic Expression and Purification of JsMYB305 Transcription Factor in Jasminum sambac

  Objective  The recombinant protein of fragrance-regulating transcription factor JsMYB305 was obtained in preparation for studies on the molecular mechanism of terpenoid-regulation and interacting proteins of the gene in Jasminum sambac.

  Methods  Coding sequence of JsMYB305 was constructed into prokaryotic expression vector pGEX-4T-1 by enzyme digestion and ligation, then, transformed into the BL21 (DE3) expressing strain. The protein expression was induced by IPTG, and the recombinant protein separated and purified using GST affinity resin followed by western blot for positive identification.

  Result  After induction by 0.2 mmol·L⁻¹ IPTG, the recombinant protein was purified at the optimized temperature of 28 ℃ for 4 h and eluted with 20 mmol·L⁻¹ GSH for purification. The western blot confirmed the protein weight to be as expected.

  Conclusion  The recombinant protein of JsMYB305 was successfully obtained to pave the way for further studies on the search for the interacting proteins by GST-pull down technique and the binding of the gene to specific promoter sites by EMSA.