Skip Navigation


MBE Advance Access originally published online on February 21, 2008
Molecular Biology and Evolution 2008 25(5):980-996; doi:10.1093/molbev/msn047
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Supplementary Data
Right arrow All Versions of this Article:
25/5/980    most recent
msn047v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Larroux, C.
Right arrow Articles by Degnan, B. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Larroux, C.
Right arrow Articles by Degnan, B. M.
Social Bookmarking
 Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2008. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org

Research Articles

Genesis and Expansion of Metazoan Transcription Factor Gene Classes

Claire Larroux*, Graham N. Luke{dagger}, Peter Koopman{ddagger}, Daniel S. Rokhsar§,||, Sebastian M. Shimeld and Bernard M. Degnan*

* School of Integrative Biology, The University of Queensland, Brisbane, Queensland, Australia
{dagger} School of Biological Sciences, The University of Reading, Whiteknights, Reading, United Kingdom
{ddagger} Institute of Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
§ US Department of Energy Joint Genome Institute, Walnut Creek, CA
|| Department of Molecular and Cell Biology, Center for Integrative Genomics, University of California, Berkeley
Department of Zoology, University of Oxford, Oxford, UK

E-mail: b.degnan{at}uq.edu.au.

Accepted for publication February 12, 2008.

We know little about the genomic events that led to the advent of a multicellular grade of organization in animals, one of the most dramatic transitions in evolution. Metazoan multicellularity is correlated with the evolution of embryogenesis, which presumably was underpinned by a gene regulatory network reliant on the differential activation of signaling pathways and transcription factors. Many transcription factor genes that play critical roles in bilaterian development largely appear to have evolved before the divergence of cnidarian and bilaterian lineages. In contrast, sponges seem to have a more limited suite of transcription factors, suggesting that the developmental regulatory gene repertoire changed markedly during early metazoan evolution. Using whole-genome information from the sponge Amphimedon queenslandica, a range of eumetazoans, and the choanoflagellate Monosiga brevicollis, we investigate the genesis and expansion of homeobox, Sox, T-box, and Fox transcription factor genes. Comparative analyses reveal that novel transcription factor domains (such as Paired, POU, and T-box) arose very early in metazoan evolution, prior to the separation of extant metazoan phyla but after the divergence of choanoflagellate and metazoan lineages. Phylogenetic analyses indicate that transcription factor classes then gradually expanded at the base of Metazoa before the bilaterian radiation, with each class following a different evolutionary trajectory. Based on the limited number of transcription factors in the Amphimedon genome, we infer that the genome of the metazoan last common ancestor included fewer gene members in each class than are present in extant eumetazoans. Transcription factor orthologues present in sponge, cnidarian, and bilaterian genomes may represent part of the core metazoan regulatory network underlying the origin of animal development and multicellularity.

Key Words: developmental genes • Amphimedon queenslandica • sponge • homeodomain • Sox • Fox • T-box


Billie Swalla, Associate Editor


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
Phil Trans R Soc BHome page
S. M. Degnan and B. M. Degnan
The initiation of metamorphosis as an ancient polyphenic trait and its role in metazoan life-cycle evolution
Phil Trans R Soc B, February 27, 2010; 365(1540): 641 - 651.
[Abstract] [Full Text] [PDF]


Home page
Cold Spring Harb Symp Quant BiolHome page
G.S. Richards and B.M. Degnan
The Dawn of Developmental Signaling in the Metazoa
Cold Spring Harb Symp Quant Biol, November 10, 2009; (2009) sqb.2009.74.028v1.
[Abstract] [PDF]


Home page
Mol Biol EvolHome page
J. Nehyba, R. Hrdlickova, and H. R. Bose
Dynamic Evolution of Immune System Regulators: The History of the Interferon Regulatory Factor Family
Mol. Biol. Evol., November 1, 2009; 26(11): 2539 - 2550.
[Abstract] [Full Text] [PDF]


Home page
Mol Biol EvolHome page
E. A. Sperling, K. J. Peterson, and D. Pisani
Phylogenetic-Signal Dissection of Nuclear Housekeeping Genes Supports the Paraphyly of Sponges and the Monophyly of Eumetazoa
Mol. Biol. Evol., October 1, 2009; 26(10): 2261 - 2274.
[Abstract] [Full Text] [PDF]


Home page
Phil Trans R Soc BHome page
D. H. Erwin
Early origin of the bilaterian developmental toolkit
Phil Trans R Soc B, August 12, 2009; 364(1527): 2253 - 2261.
[Abstract] [Full Text] [PDF]


Home page
Mol Biol EvolHome page
I. Braasch, J.-N. Volff, and M. Schartl
The Endothelin System: Evolution of Vertebrate-Specific Ligand-Receptor Interactions by Three Rounds of Genome Duplication
Mol. Biol. Evol., April 1, 2009; 26(4): 783 - 799.
[Abstract] [Full Text] [PDF]


Home page
CSH ProtocolsHome page
B. M. Degnan, M. Adamska, A. Craigie, S. M. Degnan, B. Fahey, M. Gauthier, J. N.A. Hooper, C. Larroux, S. P. Leys, E. Lovas, et al.
The Demosponge Amphimedon queenslandica: Reconstructing the Ancestral Metazoan Genome and Deciphering the Origin of Animal Multicellularity
CSH Protocols, December 1, 2008; 2008(13): pdb.emo108 - pdb.emo108.
[Abstract] [Full Text]


Home page
J. Biol. Chem.Home page
J.-Y. Exposito, C. Larroux, C. Cluzel, U. Valcourt, C. Lethias, and B. M. Degnan
Demosponge and Sea Anemone Fibrillar Collagen Diversity Reveals the Early Emergence of A/C Clades and the Maintenance of the Modular Structure of Type V/XI Collagens from Sponge to Human
J. Biol. Chem., October 17, 2008; 283(42): 28226 - 28235.
[Abstract] [Full Text] [PDF]


Home page
Biol. Bull.Home page
B. Fahey, C. Larroux, B. J. Woodcroft, and B. M. Degnan
Does the High Gene Density in the Sponge NK Homeobox Gene Cluster Reflect Limited Regulatory Capacity?
Biol. Bull., June 1, 2008; 214(3): 205 - 217.
[Abstract] [Full Text] [PDF]



Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.