title: A polypeptide from shark troponin I can inhibit angiogenesis and tumor growth.
abstract: The shark troponin I gene (TnI) was found for the first time in this study to inhibit endothelial cell proliferation and angiogenesis. This shark TnI had 68.9% amino acid homology with human TnI, whereas the polypeptide from Lys91 to Leu123, which is thought to be the active site of TnI, had 78.8% homology with the corresponding fragment of human TnI. However, the polypeptide of shark had higher activity to inhibit the proliferation of HUVEC and tumor cell lines than that of human TnI. To investigate the anti-angiogenesis and anti-tumor effect of the shark TnI polypeptide, the DNA sequence of polypeptide (Lys91-Leu123) of white-spot catshark TnI(psTnI) was cloned and fused with the His-SUMO cDNA, followed by expression in Escherichia coli. After its purification by Ni(2+) affinity chromatography, the fusion His-SUMO-psTnI protein was digested with the SUMO enzyme to release psTnI. The inhibitory ability of this recombinant shark TnI polypeptide for angiogenesis was confirmed by chicken embryo allantoic membrane (CAM) test and IHC analysis. It was also found by breast carcinoma xenograft study in Balb/c mice that this polypeptide could inhibit tumor growth in vivo.
authors.affiliation: College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
authors.forename: Qiuling
authors.initials: Q
authors.lastname: Xie
authors.forename: Sheng
authors.initials: S
authors.lastname: Yao
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Chen
authors.forename: Lihui
authors.initials: L
authors.lastname: Xu
authors.forename: Wendan
authors.initials: W
authors.lastname: Peng
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Qihao
authors.initials: Q
authors.lastname: Zhang
authors.forename: Xu-Fang
authors.initials: XF
authors.lastname: Liang
authors.forename: An
authors.initials: A
authors.lastname: Hong
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002642:Chick Embryo; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D042783:Endothelial Cells / Q000187:drug effects*; D004926:Escherichia coli; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D010455:Peptides / Q000235:genetics* / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D012754:Sharks / Q000235:genetics*; D013045:Species Specificity; D013778:Tetrazolium Salts; D013844:Thiazoles; D019210:Troponin I / Q000235:genetics*
chemical_list: D017931:DNA Primers; D010455:Peptides; D013778:Tetrazolium Salts; D013844:Thiazoles; D019210:Troponin I; C022616:thiazolyl blue