title: Identification of cysteine protease inhibitors that belong to cystatin family 1 in the cellular slime mold Dictyostelium discoideum.
abstract: Family 1 cystatins are cytosolic inhibitors of cysteine proteases, and they are conserved in higher eukaryotes. We characterized two newly identified family 1 cystatins of the cellular slime mold Dictyostelium discoideum, cystatin A1 and A2. Their recombinant proteins showed specific inhibitory activity against papain and cathepsin B, respectively. Using specific polyclonal antibodies, we found that cystatin A1 is stably expressed throughout the life cycle of Dictyostelium, whereas cystatin A2 expression is up-regulated during the course of development.
authors.affiliation: Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
authors.forename: Medhat S
authors.initials: MS
authors.lastname: El-Halawany
authors.forename: Susumu
authors.initials: S
authors.lastname: Ohkouchi
authors.forename: Hideki
authors.initials: H
authors.lastname: Shibata
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Hitomi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Maki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015891:Cystatins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004023:Dictyostelium / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; D015800:Protozoan Proteins; D011994:Recombinant Proteins