title: Tail regression in Ciona intestinalis (Prochordate) involves a Caspase-dependent apoptosis event associated with ERK activation.
abstract: Two apoptotic events take place during embryonic development of Ciona intestinalis. The first concerns extra-embryonic cells and precedes hatching. The second controls tail regression at metamorphosis, occurs through a polarized wave originating from tail extremity, and is caspase dependent. This was shown by: (1) in vivo incorporation of a fluorescent marker of caspase activation in different cell types of the tail; (2) detection of an activated form of caspase 3-like protein by western blotting; and (3) failure of 30% of larvae to undergo metamorphosis after treatment of fertilized eggs with a pan-caspase inhibitor. In addition, Ciona embryos express a single ERK protein, specifically phosphorylated at metamorphosis. ERK activation was shown to be located in cells of the tail. Addition of MEK inhibitor in the culture medium prevented ERK activation and metamorphosis. In silico analysis of Ciona genome pointed to 15 caspases with high homology with humans, and a single ERK gene with high homology to both mammalian ERK1 and ERK2. It is concluded that the sequence of events leading to metamorphosis includes ERK phosphorylation followed by caspase-dependent apoptosis and tail regression.
authors.affiliation: UMR 5539 Centre National de la Recherche Scientifique, Dynamique Moléculaire des Interactions Membranaires, Université Montpellier II place E. Bataillon 34095 Montpellier cedex 05, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Chambon
authors.forename: Jonathan
authors.initials: J
authors.lastname: Soule
authors.forename: Pascal
authors.initials: P
authors.lastname: Pomies
authors.forename: Philippe
authors.initials: P
authors.lastname: Fort
authors.forename: Alain
authors.initials: A
authors.lastname: Sahuquet
authors.forename: Daniel
authors.initials: D
authors.lastname: Alexandre
authors.forename: Paul-Henri
authors.initials: PH
authors.lastname: Mangeat
authors.forename: Stephen
authors.initials: S
authors.lastname: Baghdiguian
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D053148:Caspase 3; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D002938:Ciona intestinalis / Q000196:embryology / Q000235:genetics / Q000254:growth & development*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004625:Embryo, Nonmammalian; D005260:Female; D006801:Humans; D007814:Larva / Q000187:drug effects; D008297:Male; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017386:Sequence Homology, Amino Acid; D013623:Tail / Q000196:embryology / Q000254:growth & development* / Q000473:pathology; D014404:Tubulin / Q000378:metabolism
chemical_list: D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D014404:Tubulin; D020929:Mitogen-Activated Protein Kinase Kinases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases