title: Microinjection of an antibody against the cysteine-protease involved in male chromatin remodeling blocks the development of sea urchin embryos at the initial cell cycle.
abstract: We reported recently that the inhibition of cysteine-proteases with E-64-d disturbs DNA replication and prevents mitosis of the early sea urchin embryo. Since E-64-d is a rather general inhibitor of thiol-proteases, to specifically target the cysteine-protease previously identified in our laboratory as the enzyme involved in male chromatin remodeling after fertilization, we injected antibodies against the N-terminal sequence of this protease that were able to inhibit the activity of this enzyme in vitro. We found that injection of these antibodies disrupts the initial zygotic cell cycle. As shown in this report in injected zygotes a severe inhibition of DNA replication was observed, the mitotic spindle was not correctly bipolarized the embryonic development was aborted at the initial cleavage division. Consequently, the injection of these antibodies mimics perfectly the effects previously described for E-64-d, indicating that the effects of this inhibitor rely mainly on the inhibition of the cysteine-protease involved in male chromatin remodeling after fertilization. These results further support the crucial role of this protease in early embryonic development.
authors.affiliation: Department of Biochemistry and Molecular Biology, Universidad de Concepción, Casilla, Chile.
authors.forename: Marcia
authors.initials: M
authors.lastname: Puchi
authors.forename: Karin
authors.initials: K
authors.lastname: Quiñones
authors.forename: Carolina
authors.initials: C
authors.lastname: Concha
authors.forename: Claudio
authors.initials: C
authors.lastname: Iribarren
authors.forename: Paula
authors.initials: P
authors.lastname: Bustos
authors.forename: Violeta
authors.initials: V
authors.lastname: Morin
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Genevière
authors.forename: Maria
authors.initials: M
authors.lastname: Imschenetzky
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects / Q000276:immunology*; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects / Q000502:physiology*; D003546:Cysteine Endopeptidases / Q000276:immunology* / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000276:immunology* / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects; D047108:Embryonic Development / Q000187:drug effects / Q000502:physiology; D005306:Fertilization / Q000502:physiology; D007136:Immunoglobulins / Q000187:drug effects; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D008845:Microinjections / Q000379:methods; D008938:Mitosis / Q000187:drug effects; D012617:Sea Urchins / Q000196:embryology*; D015053:Zygote / Q000166:cytology
chemical_list: D000906:Antibodies; D015853:Cysteine Proteinase Inhibitors; D007136:Immunoglobulins; D003546:Cysteine Endopeptidases; D007930:Leucine; C024974:E 64