A5049101604- Developmental Biology and Gene Regulation
- Congenital heart defects research
- Ichthyology and Marine Biology
- RNA Research and Splicing
- RNA modifications and cancer
- RNA and protein synthesis mechanisms
- Zebrafish Biomedical Research Applications
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- MicroRNA in disease regulation
- Animal Genetics and Reproduction
- Marine animal studies overview
- Retinal Development and Disorders
- Hemispheric Asymmetry in Neuroscience
- Morphological variations and asymmetry
- Paleontology and Evolutionary Biology
- Physiological and biochemical adaptations
- Neurogenesis and neuroplasticity mechanisms
- Single-cell and spatial transcriptomics
- Neurobiology and Insect Physiology Research
- Reproductive biology and impacts on aquatic species
- Identification and Quantification in Food
- Renal and related cancers
- Epigenetics and DNA Methylation
- Genomics and Chromatin Dynamics
- Pluripotent Stem Cells Research
Centre National de la Recherche Scientifique
2015-2025
Biologie Intégrative des Organismes Marins
2016-2025
Sorbonne Université
2015-2025
Observatoire Océanologique de Banyuls-sur-Mer
2018-2024
Université Paris Cité
2015-2019
Station Biologique de Roscoff
2012-2017
Université Européenne de Bretagne
2011-2015
Institut thématique Biologie cellulaire, développement et évolution
2013
Bipar
2005-2010
Immunologie et Neurogénétique Expérimentales et Moléculaires
2008
We have replaced part of the mouse homeogene Otx2 coding region with E. coli lacZ sequence, thus creating a null allele Otx2. By 9.5 dpc, homozygous mutant embryos are characterized by absence forebrain and midbrain regions. From early to midstreak stages, endomesodermal cells expressing fail be properly localized anteriorly. In ectodermal layer, transcription is progressively extinguished, being barely detectable late streak stage. These data suggest that expression in endomesoderm ectoderm...
The stomach, a hallmark of gnathostome evolution, represents unique anatomical innovation characterized by the presence acid- and pepsin-secreting glands. However, occurrence these glands in species is not universal; nineteenth century French zoologist Cuvier first noted that some teleosts lacked stomach. Strikingly, Holocephali (chimaeras), dipnoids (lungfish) monotremes (egg-laying mammals) also lack acid secretion gastric cellular phenotype. Here, we test hypothesis loss phenotype...
rRNA processing pathways in humans have been reinverstigated through systematic Northernblot hybridizations of HeLa cell nuclear RNA with a collection digoxigenine‐lebeled rDNA probes from different regions the human transcriptional unit. In addition to known 45S, 41S, 32S and 21S pre‐rRNA, two major pre‐rRNA fractions were identified; ‘30S’ (about 5800 nucleotides) precursor 18S containing an external transcribed spacer at 5′ end (ETS) internal trnscribed (ITS) 1 sequences ‘12S’ 950 5.8S...
INTRODUCTIONDue to their large size and long generation times, chondrichthyans have been largely ignored by geneticists. However, key phylogenetic position makes them ideal subjects study the molecular bases of important morphological physiological innovations that characterize jawed vertebrates. Such analyses are crucial understanding origin complex genetic mechanisms unraveled in osteichthyans. The small spotted dogfish Scyliorhinus canicula, a representative largest order extant sharks,...
Left-right asymmetries in the epithalamic region of brain are widespread across vertebrates, but their magnitude and laterality varies among species. Whether these differences reflect independent origins forebrain or taxa-specific diversifications an ancient vertebrate feature remains unknown. Here we show that catshark Scyliorhinus canicula lampreys Petromyzon marinus Lampetra planeri exhibit conserved molecular between left right developing habenulae. Long-term pharmacological treatments...
Abstract The support of pluripotent cells over time is an essential feature development. In eutherian embryos, pluripotency maintained from naïve states in peri-implantation to primed at gastrulation. To understand how these emerged, we reconstruct the evolutionary trajectory Pou5 gene family, which contains central factor OCT4. By coupling sequence analysis with functional studies mouse embryonic stem cells, find that ability POU5 proteins originated gnathostome lineage, prior generation...
By their phylogenetic position and marked epithalamic asymmetries, lampreys are relevant models for understanding the formation evolution of this trait across vertebrates. In study, we use a transcriptomic approach to identify novel signature markers characterize highly asymmetric, bipartite organization habenulae in lampreys. Lamprey subdivided into two complementary subdomains related, respectively, lateral/ventral medial/dorsal jawed vertebrates: dorsal, right-restricted subdomain...
Mechanisms of ITS2 excision from pre-rRNA remain largely elusive. In mammals, at least two endonucleolytic cleavages are involved, which result in the transient accumulation precursors to 5.8S rRNA termed 8S and 12S RNAs. We have sequenced four new species Mus genus investigated its secondary structure using thermodynamic prediction comparative approach. Phylogenetic evidence supports an folding organized domains extending a preserved structural core. This is also conserved for previously...
Abstract Background The three vertebrate pituitary glycoprotein hormones (GPH) are heterodimers of a common α and specific β subunit. In human, they located on different chromosomes but in similar genomic environment. We took advantage the availability EST data from two cartilaginous fish species as well lamprey to identify their repertoire neurotrophin, lin7 KCNA gene family members which close environment gphβ . Gphα absent outside vertebrates related genes present both protostomes...
Classical hypotheses regarding the evolutionary origin of paired appendages propose transformation precursor structures (gill arches and lateral fin folds) into fins. During development, gnathostome form as outgrowths body wall somatopleure, a tissue composed somatic plate mesoderm (LPM) overlying ectoderm. In amniotes, LPM contributes connective to abaxial musculature forms ventrolateral dermis interlimb wall. The phylogenetic distribution this character is uncertain because lineage...
In dogfish, spermatogenesis progresses from a restricted germinative zone, which lines the dorsal testicular vessel. Single spermatogonia (A(s)), including spermatogonial stem cells (SSCs), produce successively paired (A(p)), undifferentiated (A(u4) to A(u512)), and differentiated (A(d1) A(d8)) preleptotene (PL) spermatocytes through 13 mitoses. Dogfish subpopulations present classical morphological characteristics but cannot be distinguished on basis of molecular markers. This...
Abstract In order to characterize the molecular bases of mineralizing cell evolution, we targeted type X collagen, a nonfibrillar network forming collagen encoded by Col10a1 gene. It is involved in process endochondral ossification ray-finned fishes and tetrapods (Osteichthyes), but until now unknown cartilaginous (Chondrichthyes). We show that holocephalans elasmobranchs have respectively five six tandemly duplicated gene copies display conserved genomic synteny with osteichthyan genes. All...
The forebrain is the brain region which has undergone most dramatic changes through vertebrate evolution. Analyses conducted in lampreys are essential to gain insight into broad ancestral characteristics of at dawn vertebrates, and understand molecular basis for diversifications that have taken place cyclostomes gnathostomes following their splitting. Here, we report embryonic expression patterns 43 lamprey genes, coding transcription factors or signaling molecules known be involved cell...
The basic anatomy of the elasmobranch brain has been previously established after studying organization different subdivisions in adult brain. However, despite relatively abundant immunohistochemical and hodologic studies performed species sharks skates, some remains unclear. present study focuses on regions which basis anatomical data adults remain controversial, such as subpallium, mainly striatal subdivision. Taking advantage great potential lesser spotted dogfish, <i>Scyliorhinus...
The neuropeptide gonadotropin-releasing hormone (GnRH) plays an important role in the control of reproductive functions. Vertebrates possess multiple GnRH forms that are classified into three main groups, namely GnRH1, GnRH2, and GnRH3. In order to gain more insights gene family vertebrates, we sought identify which paralogs this present cartilaginous fish. For purpose, searched genomes and/or transcriptomes representative species group, small-spotted catshark, Scyliorhinus canicula, whale...
The processing of pre-rRNA in eukaryotic cells involves a complex pattern nucleolytic reactions taking place preribosomes with the participation several nonribosomal proteins and small nuclear RNAs. mechanism these remains largely unknown, mainly because absence faithful vitro assays for most steps. We have developed system using transient expression ribosomal minigenes transfected into cultured mouse cells. Truncated or human rRNA genes are faithfully transcribed under control promoter...
Using a degenerate PCR approach, we performed an exhaustive search of Otx genes in the reedfish Erpetoichthys calabaricus, dogfish Scyliorhinus canicula, and hagfish Myxine glutinosa. Three novel were identified each these species, their deduced protein sequences determined over large C-terminal fragment located immediately downstream homeodomain. Like lamprey osteichthyan counterparts, nine display tandem duplication 20–25-residue domain, which appears to be hallmark all craniate thus far,...