Construction of a synthetic Araneus ventricosus dragline silk gene multimer and its expression in Escherichia coli

One of the most representative core gene sequence of Araneus ventricosus dragline silk protein partial cDNA monomer (JN857964.2) was selected and multimerized using a “head-to-tail” strategy by compatible but nonregenerable sites at both ends resulting in a concatemer of 16 contiguous monomers. This concatemer was cloned into pET-28a(+) expression vector and transformed into Escherichia coli. A 52.6 kDa silk protein was successfully expressed and detected by SDS–PAGE and confirmed by Western blotting. A maximum yield of the silk protein was expressed with 7.06 mM IPTG after 5 h incubation. This is the first report on the construction and overexpression of a A. ventricosus dragline silk multimeric gene construct and the results from our study will provide a reference point for further exploration and development of large-scale production of spider silk protein.