Production of recombinant silk fibroin with basic fibroblast growth factor binding affinity

Abstract

　　Silk fibroin (SF) composed of heavy chains (Fib-H), light chains (Fib-L), and fibrohexamerin, is a desirable material for many tissue engineering applications due to its superior moldability and biocompatibility. In this work, we produced transgenic silkworm lines, which express a recombinant protein comprising the basic fibroblast growth factor (bFGF)-binding P7 peptide with homology to bFGF receptors introduced at the C-terminus of the fibroin L-chain, using the piggyBac vector. As a result, one transgenic line 2-23 expressed recombinant fibroin L-chain protein at a relative amount of 26.75 % of all L-chains (which also comprise endogenous L-chains), which indicates high bFGF binding affinity of recombinant SF compared to that of the control (non-transgenic silkworm SF). Our result will contribute to the development of medical application of recombinant SF.