Preparation of cFGF-21.

<p>(A) SDS-PAGE gel analysis of cFGF-21 expression. Lane 1: Protein molecular mass marker; lane 2: The lysates of Rosetta (DE3) cells containing pSUMO-cFGF21 without induced by IPTG; Lane 3: The lysates of Rosetta (DE3) cells containing pSUMO-cFGF21 with induced by IPTG; Lane 4: The supernatant of Rosetta (DE3) cells containing pSUMO-cFGF21 with induced by IPTG; Lane 5: The precipitation of Rosetta (DE3) cells containing pSUMO-cFGF21 with induced by IPTG. (B) SDS-PAGE gel analysis of purified PEG-FGF21. The cFGF21 protein was purified by a Ni Sepharose 6 Fast Flow column. Lane 1: Protein molecular mass marker; lane 2: cFGF-21. (C) The purity of cFGF-21. The purity of cFGF-21 was analyzed by HPLC.