Archives de la catégorie development

Vertebrate limb bud formation is initiated by localized epithelial-to-mesenchymal transition

Vertebrate limbs first emerge as small buds at specific locations along the trunk. Although a fair amount is known about the molecular regulation of limb initiation and outgrowth, the cellular events underlying these processes have remained less clear. We show that the mesenchymal limb progenitors arise through localized epithelial-to-mesenchymal transition (EMT) of the coelomic epithelium specifically within the presumptive limb fields. This EMT is regulated at least in part by Tbx5 and Fgf10, two genes known to control limb initiation. This work shows that limb buds initiate earlier than previously thought, as a result of localized EMT rather than differential proliferation rates.

Gros J, Tabin CJ.

Science 14 March 2014:  Vol. 343 no. 6176 pp. 1253-1256, doi:10.1126/science.1248228

, , ,

Poster un commentaire

A Switch Between Topological Domains Underlies HoxD Genes Collinearity in Mouse Limbs

Guillaume Andrey, Thomas Montavon, Bénédicte Mascrez, Federico Gonzalez, Daan Noordermeer, Marion Leleu, Didier Trono, François Spitz, Denis Duboule

Science 7 June 2013: Vol. 340 no. 6137 dpi: 10.1126/science.1234167

Editors Summary

During limb development, the time and place of Hox transcription are fixed by respective gene position within the gene cluster. Andrey et al. (p. 1234167; see the Perspective by Rodrigues and Tabin) found that this enigmatic property results from the opposite and successive actions of two large regulatory landscapes located on either side of the mouse Hox locus. In the early phase, one of these topological domains regulates transcription in the proximal limb until a switch occurs toward the other topological domain, which takes over the regulation in the distally developing digits. As a side effect of this antagonistic regulatory strategy, cells in-between have lessened Hox transcription, which generates the wrist.

11F80FB6-2F3F-4EE8-BD7C-1BCAB062F790.jpg

Lire la suite »

,

Poster un commentaire

Macrophages are required for adult salamander limb regeneration

Macrophages are required for adult salamander limb regeneration

James W. Godwina, Alexander R. Pinto, and Nadia A. Rosenthal

Published online before print May 20, 2013, doi: 10.1073/pnas.1300290110

Lire la suite »

Poster un commentaire

Emergence and Diversification of Fly Pigmentation Through Evolution of a Gene Regulatory Module

Laurent Arnoult, Kathy F. Y. Su, Diogo Manoel, Caroline Minervino, Justine Magriña, Nicolas Gompel, and Benjamin Prud’homme

Science 22 March 2013: 339 (6126), 1423-1426. doi: 10.1126/science.1233749

Capture d’écran 2013-03-22 à 20.11.43.JPG

Lire la suite »

Poster un commentaire

Genomic Diversity and Evolution of the Head Crest in the Rock Pigeon

Genomic Diversity and Evolution of the Head Crest in the Rock Pigeon

Shapiro MD et al

Science DOI: 10.1126/science.1230422


Or, les lois de la physique contiennent la notion de champ d’orientation, qui une fois comprise implique un sens de déformation des animaux gravé dans les tissus. [Vincent Fleury, Source]

Gravé dans les tissus peut-être, mais par l’expression génique 😉

Lire la suite »

Poster un commentaire

Inducible genetic system for the axolotl

Inducible genetic system for the axolotl

Jessica L. Whited, Jessica A. Lehoczky, and Clifford J. Tabin

PNAS 2012 ; published ahead of print August 6, 2012, doi:10.1073/pnas.1211816109

Lire la suite »

,

Poster un commentaire

Alzheimer’s-Related Peptide Amyloid-β Plays a Conserved Role in Angiogenesis

Alzheimer’s-Related Peptide Amyloid-β Plays a Conserved Role in Angiogenesis

Cameron DJ, Galvin C, Alkam T, Sidhu H, Ellison J, et al. (2012)

PLoS ONE 7(7): e39598. doi:10.1371/journal.pone.003959810.1371/journal.pone.0039598

A3DD321A-E854-44CA-91A9-6ACCD131BCAF.jpg

Lire la suite »

Poster un commentaire

Transient downregulation of Bmp signalling induces extra limbs in vertebrates

Transient downregulation of Bmp signalling induces extra limbs in vertebrates

Bea Christen, Alexandre Miguel Cavaco Rodrigues, Monserrat Barragán Monasterio, Carme Fabregat Roig and Juan Carlos Izpisua Belmonte

Development 139, 2557-2565 (2012) doi:10.1242/dev.078774

Lire la suite »

, , , , ,

Poster un commentaire

Gastrulation and pre-gastrulation morphogenesis, inductions, and gene expression: similarities and dissimilarities between urodelean and anuran embryos

Gastrulation and pre-gastrulation morphogenesis, inductions, and gene expression: similarities and dissimilarities between urodelean and anuran embryos

Teruo Kaneda & Jun-ya Doi Motoki

Developmental Biology Available online 25 May 2012 doi :10.1016/j.ydbio.2012.05.019

Lire la suite »

Poster un commentaire

Modeling Planarian Regeneration: A Primer for Reverse-Engineering the Worm

Modeling Planarian Regeneration: A Primer for Reverse-Engineering the Worm

Lobo D, Beane WS, Levin M

PLoS Comput Biol 8(4): e1002481. doi:10.1371/journal.pcbi.1002481

figE.jpg

(E) A post-pharyngeal fragment treated with octanol and with the nerve cords partially amputated regenerates into a quadruple-headed worm.

Lire la suite »

Poster un commentaire