title: Cysteine-protease involved in male chromatin remodeling after fertilization co-localizes with alpha-tubulin at mitosis.
abstract: We postulated an essential role for a cysteine-protease in sea urchins sperm histones degradation which follows fertilization. We now report the purification of this enzyme, the determination of its N-terminal amino acid sequence and the localization of the protein with antibodies generated against this amino-terminal peptide. The immunofluorescence data confirmed the presence of this enzyme in the nucleus of unfertilized eggs. After fertilization labeling is observed both in female and male pronuclei suggesting a rapid recruitment of the enzyme to the male pronuclei. Interestingly, we have found that this cysteine-protease persists in the nucleus of the zygotes during S phase of the cell cycle and co-localizes with alpha-tubulin that organizes the mitotic spindle during the initial embryonic cell division.
authors.affiliation: Department of Molecular Biology, Universidad de Concepción, Casilla, Concepción, Chile.
authors.forename: Carolina
authors.initials: C
authors.lastname: Concha
authors.forename: Violeta
authors.initials: V
authors.lastname: Morin
authors.forename: Paula
authors.initials: P
authors.lastname: Bustos
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Genevière
authors.forename: Margarete M S
authors.initials: MM
authors.lastname: Heck
authors.forename: Marcia
authors.initials: M
authors.lastname: Puchi
authors.forename: Maria
authors.initials: M
authors.lastname: Imschenetzky
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology; D042002:Chromatin Assembly and Disassembly / Q000502:physiology*; D003546:Cysteine Endopeptidases / Q000378:metabolism / Q000502:physiology*; D005260:Female; D005306:Fertilization / Q000502:physiology*; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D008938:Mitosis / Q000502:physiology*; D010063:Ovum / Q000378:metabolism; D016196:S Phase; D012617:Sea Urchins / Q000196:embryology; D014018:Tissue Distribution; D014404:Tubulin / Q000378:metabolism*; D015053:Zygote / Q000166:cytology / Q000201:enzymology / Q000378:metabolism
chemical_list: D014404:Tubulin; D003546:Cysteine Endopeptidases