title: A quicker degradation rate is yielded by a novel kind of transgenic silk fibroin consisting of shortened silk fibroin heavy chains fused with matrix metalloproteinase cleavage sites.
abstract: Degradation performance of silk fibroin is an important property for its medical applications. Herein we constructed a shortened silk fibroin heavy chain protein fused with a matrix metalloproteinase cleavage site (SSFH-MMP) along with a glutathione S-transferase tag ahead. The digestion assay shows it can be cut by matrix metalloproteinase-2 (MMP-2) at its MMP cleavage site. Furthermore, we introduced the SSFH-MMP into silk fibroin by genetic modification of silkworms in order to increase the degradation rate of the silk fibroin. After acquisition of a race of transgenic silkworms with the coding sequence of the MMP cleavage site in their genomic DNA, we tested some properties of their silk fibroin designated TSF-MMP. The results show that the TSF-MMP has MMP cleavage sites and yields a quicker degradation rate during dilution in MMP-2 enzyme buffer or implantation into tumor tissues compared with that of normal silk fibroin. Moreover, the TSF-MMP is in vitro non-toxic to human bone marrow mesenchymal stem cells (hBM-MSCs) indicating that the TSF-MMP may become a biomaterial with a quicker degradation rate for its medical applications.
authors.affiliation: Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, 212013, People's Republic of China, huanggp@ujs.edu.cn.
authors.forename: Guoping
authors.initials: G
authors.lastname: Huang
authors.forename: Danfeng
authors.initials: D
authors.lastname: Yang
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Sun
authors.forename: Jianping
authors.initials: J
authors.lastname: Huang
authors.forename: Keping
authors.initials: K
authors.lastname: Chen
authors.forename: Chunxia
authors.initials: C
authors.lastname: Zhang
authors.forename: Huiqing
authors.initials: H
authors.lastname: Chen
authors.forename: Qin
authors.initials: Q
authors.lastname: Yao
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D001665:Binding Sites; D012831:Bombyx; D002478:Cells, Cultured; D017931:DNA Primers; D005349:Fibroins / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D020782:Matrix Metalloproteinases / Q000737:chemistry*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D047011:Silk / Q000737:chemistry*
chemical_list: D017931:DNA Primers; D047011:Silk; D005349:Fibroins; D020782:Matrix Metalloproteinases