Expression and purification of porcine Akirin2 in Escherichia coli

Akirin2 is a recently discovered gene related to immune responses that also plays an important role in skeletal myogenesis. In this study, in order to scale up the production of recombinant porcine Akirin2 (pAkirin2), we report the expression and purification of a His-tagged version of recombinant pAkirin2 in Escherichia coli. The pAkirin2 is a polypeptide of 203 amino acids containing 42 rare codons. The recombinant pAkirin2 was expressed as an N-terminal fusion protein with His6 tag in E. coli Rosetta (DE3) host strain. The protein was purified by Ni-IDA affinity chromatography, yielding over 90% highly purified recombinant pAkirin2, with a considerable yield of 4 mg/L. The purified recombinant pAkirin2 was confirmed by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometer analysis. The refolded purified recombinant pAkirin2 significantly promoted the proliferation of C2C12 cells, indicating that it was active. This report provides a reliable technique for recombinant expression and purification of pAkirin2 protein.