Programas divergentes de expressão de gene, mas planos corporais semelhantes

Current Biology, Volume 19, Issue 23, 2014-2019, 19 November 2009

Highly Divergent Gene Expression Programs Can Lead to Similar Chordate Larval Body Plans

Daniel Sobral 1, 2, Olivier Tassy 1, 3 and Patrick Lemaire 1,

1 Institut de Biologie du Développement de Marseille-Luminy (IBDML), UMR6216, CNRS, Université de la Méditerranée, Campus de Luminy, Case 907, F-13288 Marseille Cedex 09, France

Corresponding author

Corresponding author

2 Present address: European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK

3 Present address: Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA


Summary

The diversity of animal morphologies is thought to result largely from spatial or temporal variations in gene expression. Conversely, we explored here the extent of divergence in transcriptional expression patterns compatible with a common morphological output, the chordate larva. We compared two organisms that share a prototypical tadpole larval body plan but are separated by over half a billion years of divergent evolution: the zebrafish (Danio rerio) and the ascidian Ciona intestinalis, an invertebrate chordate belonging to the sister group of vertebrates [1]. The large databases of whole-mount in situ hybridization expression patterns available for these two species allowed us to carry out a systematic large-scale comparison of spatiotemporal expression patterns of 1103 groups of orthologous genes. We found an extensive overall divergence in gene expression profiles between the two species that was similar at all developmental stages and did not discriminate developmental regulators from their targets. The level of conservation in individual tissues, however, varied. Conservation of tissue-specific expression patterns was highest in tissues involved in locomotion, including muscle, notochord, and the central nervous system. Thus, a broad divergence in gene expression profiles is compatible with the conservation of similar body plans across large evolutionary distances.

+++++

FREE PDF GRÁTIS

PERGUNTA INDISCRETA DESTE BLOGGER:

Como é que fica agora a noção de os planos corporais serem resultados de programas de expressão de gene???