Fish diversity
Laura (6)
Species richness in vertebrates
Genome and biodiversity
- Genome duplication and differential rediploidisation
- Transposable elements
- Sex chromosomes and sex determination
Sex determination systems in vertebrates
Ezaz et al. 2006
Mank et al. 2006
Diversity of sex determination in fish
Others:
- Autosomal influence
- Polyfactorial
- With several sex chromosomes- With several pairs of sex
chromosomes
…
Diversity of sex determination in Poeciliids
Sex determination systems in vertebrates:
master sex-determining genes
Ezaz et al. 2006medakaXY/XX
dmrt1bY (Y)
dmrt1 (?) (Z)
DM-W (?) (W)
SRY
Dmrt1bY, a recent master sex-determining gene from the medaka fish
Oryzias latipes
Dmrt1bY, a recent master sex-determining gene from the medaka fish
Oryzias latipes
Dmrt1bY is not the universal master sex-determining gene in
fish
Tanaka et al. 2007
Sex determination evolves very rapidly in fish
Possible association with the formation of new sex-determininggenes and new sex chromosomes
Possible role in speciation?
“Speciation genes” on sex chromosomes
Qvarnström and Bailey 2009
Sex determination evolution and prezygotic reproductive isolation
X Y W Z
Fish models for the study of genetic sex determination
www.Xiphophorus.org
The genus Xiphophorus
Livebearing, freshwater fish, first described 1884 by Heckel,Genus contains three groups: Northern and Southern swordtails and platyfish~23 species described
Melanoma formation in Xiphophorus interspecific hybrids
X
X
Xiphophorus maculatus Xiphophorus hellerii
Xmrk/Xmrk; R+/R+
Xmrk/- ; R+/R-
-/- ; R-/R-
-/- ; R-/R-
Xmrk/- ; R+/R-Xmrk/- ; R-/R- - / - ; R+/R- - /- ; R-/R-
The sex-determining region of the platyfish X. maculatus
Tel
XmrkMdl RY
Cen
Egfr-bSD
XmrkMdl RY SD
P
Egfr-b
Melanoma-inducingoncogene Proto-oncogene
SD Egfr-b
Y
X
W
Sex-determining
locus
Melanoma
Macromelanophoredetermining locus
Ppuberty locus
Red-yellowlocus
WX WY XX XY YY
Positional cloning strategy
egfrbYXmrkYY
egfrbXXmrkXX X-linked
Y-linked
Bacterial artificial clones (BACs)
Homomorphic sex chromosomes in the platyfish
XY XX
Neither dmrt nor sox genes in the sex-determining
region of the platyfish
No synteny with other fish sex chromosomes
Independent origin of sex-determining genes andsex chromosomes in different fish species
Comparative sexomics in vertebrates
Mammals Fish
Origin ancient / unique recent / multiple
Master gene unique (Sry) multiple (?)
Differentiation yes restricted
Degeneration yes (Y) restricted
Suppres. recombination yes yes
Sex-specific gonad genes yes (Y) yes
Gene duplications yes yes
Transposable elements yes yes
Since 2007Equipe “Génomique Evolutive des Vertébrés“Institut de Génomique Fonctionnelle de LyonCNRS/INRA/UCBL/ENSL
Astrid Böhne Frédéric BrunetDelphine Galiana-Arnoux Christina SchultheisAmandine Darras Karim MadaniEmilie Deleva Laurie NaveDomittile Chalopin Vincent MartinJean-Nicolas Volff
Until 2006BioFuture Research Group “Evolutionary Fish Genomics”Biozentrum, University of Würzburg, Germany
Christina Schultheis Qingchun ZhouCornelia Schmidt Agnès DettaiAnne-Marie Veith Alexander FroschauerYvonne Selz Marina VucicSabine Matschl Jürgen BrandtAstrid Böhne Wolfgang BernhardtMarc Rathmann Reinhold HanelIngo Braasch Jean-Nicolas Volff
Mariam Naciri
Collaborations
Manfred Schartl (University of Würzburg, Germany)
Sylvie Samain, Jean Weissenbach (Genoscope, Evry)
Catherine Ozouf-Costaz, Agnés Dettai (Muséum Natl d’Histoire Naturelle, Paris)
Yann Guigen, Julien Bobe (INRA SCRIBE, Rennes)
Jean-Francois Baroiller, Helena D‘Cotta (CIRAD Montpellier)
Indrajit Nanda, Michael Schmid (University of Würzburg, Germany)
Stefan Chilmonczyk (INRA, Jouy en Josas, France)
Carsten Hoffman, Martin Lohse (University of Würzburg, Germany)
Christoph Winkler (University of Singapore)