title: Characterization of Hlcyst-3 as a member of cystatins from the tick Haemaphysalis longicornis.
abstract: The gene encoding cystatin from the tick Haemaphysalis longicornis has been reported previously. In the study reported here, we characterized a member of cystatins and designated it as Hlcyst-3 (H. longicornis cystatin-3). Its full-length cDNA is 602 bp, and it encodes a putative 129 amino acid protein with an obvious signal peptide. Sequence analysis revealed that it has significant homology with the known secreted cystatin. The recombinant protein was expressed in a GST-fused soluble form in Escherichia coli and was purified by affinity chromatography. The inhibitory activity of the recombinant protein against papain and cathepsin L was identified by fluorogenic substrate analysis. Real-time PCR revealed that Hlcyst-3 was mostly expressed in the tick midgut.
authors.affiliation: Department of Frontier Veterinary Medicine, Kagoshima University, Korimoto, Japan. jinlinzhou@shvri.ac.cn
authors.forename: Jinlin
authors.initials: J
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Liao
authors.forename: Haiyan
authors.initials: H
authors.lastname: Gong
authors.forename: Xuenan
authors.initials: X
authors.lastname: Xuan
authors.forename: Kozo
authors.initials: K
authors.lastname: Fujisaki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D056668:Cathepsin L / Q000378:metabolism; D015891:Cystatins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism* / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000493:pharmacokinetics / Q000494:pharmacology; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D026863:Ixodidae / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010206:Papain / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D016415:Sequence Alignment
chemical_list: D015891:Cystatins; D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D056668:Cathepsin L; D010206:Papain