Prokaryotic expression and purification of porcine Sox6

Abstract

Sox6, a member of the Sox (Sry-related HMG box) family of transcription factors, plays an important role in embryonic muscle development and adult fast myofiber maintenance. Here we report the expression and purification of a His-tagged version of recombinant porcine Sox6 (pSox6) in Escherichia coli. The recombinant pSox6 was expressed as a C-terminal fusion protein with His6 tag in the E. Coli Rosetta (DE3) host strain. The protein was purified by Ni affinity chromatography, yielding approximately 5 μg/mL. The protein was identified by western blot analysis and confirmed by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometer analysis. In vitro biological activity assay demonstrated that the refolded purified recombinant pSox6 downregulated MyHC I, Tnnt1, Tnnc1, and Tnni1 mRNA expressions in porcine myotubes, suggesting that it was active. The present study provides a reliable technique for the recombinant expression and purification of pSox6 protein.