title: Emergence of sensory structures in the developing epidermis in sepia officinalis and other coleoid cephalopods.
abstract: Embryonic cuttlefish can first respond to a variety of sensory stimuli during early development in the egg capsule. To examine the neural basis of this ability, we investigated the emergence of sensory structures within the developing epidermis. We show that the skin facing the outer environment (not the skin lining the mantle cavity, for example) is derived from embryonic domains expressing the Sepia officinalis ortholog of pax3/7, a gene involved in epidermis specification in vertebrates. On the head, they are confined to discrete brachial regions referred to as "arm pillars" that expand and cover Sof-pax3/7-negative head ectodermal tissues. As revealed by the expression of the S. officinalis ortholog of elav1, an early marker of neural differentiation, the olfactory organs first differentiate at about stage 16 within Sof-pax3/7-negative ectodermal regions before they are covered by the definitive Sof-pax3/7-positive outer epithelium. In contrast, the eight mechanosensory lateral lines running over the head surface and the numerous other putative sensory cells in the epidermis, differentiate in the Sof-pax3/7-positive tissues at stages ∼24-25, after they have extended over the entire outer surfaces of the head and arms. Locations and morphologies of the various sensory cells in the olfactory organs and skin were examined using antibodies against acetylated tubulin during the development of S. officinalis and were compared with those in hatchlings of two other cephalopod species. The early differentiation of olfactory structures and the peculiar development of the epidermis with its sensory cells provide new perspectives for comparisons of developmental processes among molluscs.
authors.affiliation: Museum National d'Histoire Naturelle (MNHN), DMPA, UMR Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), MNHN CNRS 7208, IRD 207, UPMC, CP51 75005, Paris, France; Université Pierre et Marie Curie-Paris, Paris, 6, France.
authors.forename: Auxane
authors.initials: A
authors.lastname: Buresi
authors.forename: Roger P
authors.initials: RP
authors.lastname: Croll
authors.forename: Stefano
authors.initials: S
authors.lastname: Tiozzo
authors.forename: Laure
authors.initials: L
authors.lastname: Bonnaud
authors.forename: Sébastien
authors.initials: S
authors.lastname: Baratte
mesh_terms: D000344:Afferent Pathways / Q000196:embryology*; D000818:Animals; D000831:Animals, Newborn; D049830:Cephalopoda / Q000145:classification / Q000196:embryology / Q000378:metabolism; D051959:ELAV Proteins / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian; D004817:Epidermis / Q000196:embryology* / Q000254:growth & development* / Q000294:innervation / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D051761:Paired Box Transcription Factors / Q000235:genetics / Q000378:metabolism; D010447:Peptide Hydrolases / Q000235:genetics / Q000378:metabolism; D012677:Sensation / Q000502:physiology; D049833:Sepia / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development
chemical_list: D051959:ELAV Proteins; D051761:Paired Box Transcription Factors; C021908:opacity factor; D010447:Peptide Hydrolases
keywords: Doryteuthis opalescens; Euprymna scolopes; Sepia officinalis; cephalopod; elav; epidermis development; pax3/7; sensory neurons