Developmental gene expression provides clues to relationships between sponge and eumetazoan body plans.
Elucidation of macroevolutionary transitions between diverse animal body plans remains a major challenge in evolutionary biology. We address the sponge-eumetazoan transition by analyzing expression of a broad range of eumetazoan developmental regulatory genes in Sycon ciliatum (Calcispongiae). Here we show that many members of surprisingly numerous Wnt and Tgfβ gene families are expressed higher or uniquely in the adult apical end and the larval posterior end. Genes involved in formation of the eumetazoan endomesoderm, such as β-catenin, Brachyury and Gata, as well as germline markers Vasa and Pl10, are expressed during formation and maintenance of choanoderm, the feeding epithelium of sponges. Similarity in developmental gene expression between sponges and eumetazoans, especially cnidarians, is consistent with Haeckel's view that body plans of sponges and cnidarians are homologous. These results provide a framework for further studies aimed at deciphering ancestral developmental regulatory networks and their modifications during animal body plans evolution.
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2] [3].
Sven
S
Leininger
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2].
Marcin
M
Adamski
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2].
Brith
B
Bergum
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2].
Corina
C
Guder
Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway.
Jing
J
Liu
Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway.
Mary
M
Laplante
Department of Biosciences, University of Oslo, Blindernveien 36, N-0316 Oslo, Norway.
Jon
J
Bråte
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2] Department of Biology and Centre for Geobiology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Bergen, Norway.
Friederike
F
Hoffmann
1] Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway [2] Department of Biology and Centre for Geobiology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Bergen, Norway.
Sofia
S
Fortunato
Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway.
Signe
S
Jordal
Department of Biology and Centre for Geobiology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Bergen, Norway.
Hans Tore
HT
Rapp
Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway.
Maja
M
Adamska
D000818:Animals; D001483:Base Sequence; D019521:Body Patterning / Q000235:genetics*; D003063:Cnidaria / Q000235:genetics*; D005326:Fetal Proteins / Q000235:genetics; D050980:GATA Transcription Factors / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D008969:Molecular Sequence Data; D011161:Porifera / Q000235:genetics*; D020825:T-Box Domain Proteins / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000235:genetics; D051153:Wnt Proteins / Q000235:genetics; D051176:beta Catenin / Q000235:genetics; D000098908:Brachyury Protein
D005326:Fetal Proteins; D050980:GATA Transcription Factors; D020825:T-Box Domain Proteins; D016212:Transforming Growth Factor beta; D051153:Wnt Proteins; D051176:beta Catenin; D000098908:Brachyury Protein