Transcript Folie 1 - CERIMES

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
Diversity of sex determination in fish
-
Mank et al. 2006
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
SRY
dmrt1 (?) (Z)
DM-W (?) (W)
dmrt1bY (Y)
Ezaz et al. 2006
medaka
XY/XX
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
Tanaka et al. 2007
Dmrt1bY is not the universal master sex-determining gene in fish
Sex determination evolves very rapidly in fish
Possible association with the formation of new sex-determining
genes and new sex chromosomes
Possible role in speciation?
“Speciation genes” on sex chromosomes
Qvarnström and Bailey 2009
Sex determination evolution and prezygotic reproductive isolation
XY
WZ
Fish models for the study of genetic sex determination
The genus Xiphophorus
www.Xiphophorus.org
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
Xiphophorus maculatus
Xiphophorus hellerii
X
-/- ; R-/R-
Xmrk/Xmrk ; R+/R+
X
Xmrk/- ; R+/R-
Xmrk/- ; R-/R-
Xmrk/- ; R+/R-
-/- ; R-/R-
- / - ; R+/R-
- /- ; R-/R-
The sex-determining region of the platyfish X. maculatus
Macromelanophore
determining locus
Melanomainducing
oncogene
SexRed-yellow determining
locus Proto-oncogene
locus
Tel
Cen
Y
Mdl
Xmrk
RY
SD
Egfr-b
X
Mdl
Xmrk
RY
SD
Egfr-b
SD
Egfr-b
P
W
Melanoma
puberty locus
WX WY XX
P
XY YY
Positional cloning strategy
X
XmrkX
X-linked
egfrbX
Y
XmrkY
Y-linked
egfrbY
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 and
sex chromosomes in different fish species
Comparative sexomics in vertebrates
Mammals
Fish
Origin
Master gene
Differentiation
Degeneration
ancient / unique
unique (Sry)
yes
yes (Y)
recent / multiple
multiple (?)
restricted
restricted
Suppres. recombination
Sex-specific gonad genes
Gene duplications
Transposable elements
yes
yes (Y)
yes
yes
yes
yes
yes
yes
Since 2007
Equipe “Génomique Evolutive des Vertébrés“
Institut de Génomique Fonctionnelle de Lyon
CNRS/INRA/UCBL/ENSL
Astrid Böhne
Delphine Galiana-Arnoux
Amandine Darras
Emilie Deleva
Domittile Chalopin
Jean-Nicolas Volff
Frédéric Brunet
Christina Schultheis
Karim Madani
Laurie Nave
Vincent Martin
Until 2006
BioFuture Research Group “Evolutionary Fish Genomics”
Biozentrum, University of Würzburg, Germany
Christina Schultheis
Cornelia Schmidt
Anne-Marie Veith
Yvonne Selz
Sabine Matschl
Astrid Böhne
Marc Rathmann
Ingo Braasch
Mariam Naciri
Qingchun Zhou
Agnès Dettai
Alexander Froschauer
Marina Vucic
Jürgen Brandt
Wolfgang Bernhardt
Reinhold Hanel
Jean-Nicolas Volff
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)