title: Tissue-specific expression of an hsc90 gene and nuclear translocation of the HSC90-related protein during amphibian embryogenesis.
abstract: Expression and distribution of a constitutive member of the 90 kDa heat-shock protein family, named HSC90, was investigated during amphibian embryonic development. By Northern blot analysis, two hsp90 transcripts (2.5 and 3 kb) which displayed differing developmental regulation were detected during embryogenesis. Expression of the larger transcript (3 kb), which encodes an HSC90-related protein, decreased until the gastrula stage. However, zygotic transcription for this hsc90 gene was found to start from the neurula stage, and the corresponding zygotic hsc90 transcript was specifically located by whole mount in situ hybridization in the anterior neural tube of a late neurula embryo. Later, in a tailbud embryo, hsc90 transcripts were detected in the cephalic region, neural tube, eye vesicles, branchial and mandibular arches and somites. Distribution of the HSC90-related protein was also analysed by immunohistochemistry throughout embryogenesis. As expected, the protein was strongly expressed in the cytoplasm, mainly in the periplasmic area of embryonic tissue cells. Interestingly, HSC90 was also transiently detected in the nuclear area, with this nuclear transfer depending on the chromatin condensation state, up to the blastula stage. During the process of gastrulation, nuclear translocation of HSC90 was also observed at the level of the blastopore dorsal lip, exclusively in cells undergoing invagination.
authors.affiliation: Laboratoire de Biologie Moléculaire du Développement, UA 1135 CNRS-Université Pierre et Marie Curie, Groupe "Gènes et Développement", Bâtiment C, 6ème étage, Case 16, 9 quai Saint-Bernard, F-75252 Paris Cedex 05, France, , , , , , FR.
authors.forename: Pascal
authors.initials: P
authors.lastname: Coumailleau
authors.affiliation: Laboratoire de Biologie Moléculaire du Développement, UA 1135 CNRS-Université Pierre et Marie Curie, Groupe "Gènes et Développement", Bâtiment C, 6ème étage, Case 16, 9 quai Saint-Bernard, F-75252 Paris Cedex 05, France, , , , , , FR.
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Bonnanfant-Jaïs
authors.affiliation: Laboratoire de Biologie Moléculaire du Développement, UA 1135 CNRS-Université Pierre et Marie Curie, Groupe "Gènes et Développement", Bâtiment C, 6ème étage, Case 16, 9 quai Saint-Bernard, F-75252 Paris Cedex 05, France, , , , , , FR.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Lainé
authors.affiliation: Laboratoire de Biologie Moléculaire du Développement, UA 1135 CNRS-Université Pierre et Marie Curie, Groupe "Gènes et Développement", Bâtiment C, 6ème étage, Case 16, 9 quai Saint-Bernard, F-75252 Paris Cedex 05, France, , , , , , FR.
authors.forename: N
authors.initials: N
authors.lastname: Angelier
mesh_terms: D021581:Active Transport, Cell Nucleus; D029845:Amphibian Proteins / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D047108:Embryonic Development; D005260:Female; D018507:Gene Expression Regulation, Developmental; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D008297:Male; D009928:Organ Specificity; D012455:Salamandridae / Q000196:embryology* / Q000235:genetics / Q000378:metabolism
chemical_list: D029845:Amphibian Proteins; D018841:HSP90 Heat-Shock Proteins
keywords: Amphibian; Development; Key words Heat-Shock Proteins 90; Molecular chaperones