ZFIN ID: ZDB-PUB-050318-9
T-box gene eomesodermin and the homeobox-containing Mix/Bix gene mtx2 regulate epiboly movements in the zebrafish
Bruce, A.E., Howley, C., Dixon Fox, M., and Ho, R.K.
Date: 2005
Source: Developmental dynamics : an official publication of the American Association of Anatomists   233(1): 105-114 (Journal)
Registered Authors: Bruce, Ashley, Ho, Robert K., Howley, Cristin
Keywords: zebrafish, epiboly, radial intercalation, eomesodermin, mtx2
MeSH Terms:
  • Animals
  • Blastula/metabolism
  • Gastrula/metabolism
  • Gene Expression Regulation, Developmental/physiology*
  • Membrane Proteins/genetics
  • Membrane Proteins/metabolism*
  • T-Box Domain Proteins/genetics
  • T-Box Domain Proteins/metabolism*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 15765511 Full text @ Dev. Dyn.
The T-box gene eomesodermin (eomes) has been implicated in mesoderm specification and patterning in both zebrafish and frog. Here, we describe an additional function for eomes in the control of morphogenesis. Epiboly, the spreading and thinning of an epithelial cell sheet, is a central component of gastrulation in many species; however, despite its importance, little is known about its molecular control. Here, we show that repression of eomes function in the zebrafish embryo dramatically inhibits epiboly movements. We also show that eomes regulates the expression of a zygotic homeobox transcription factor mtx2. Gene knockdown of mtx2 using antisense morpholino oligonucleotides, likewise, leads to an inhibition of epiboly; moreover, we show that knockdown of mtx2 function in the extraembryonic yolk syncytial layer only is sufficient to cause epiboly defects. Thus, we have identified two components in a molecular pathway controlling epiboly and show that interactions between deep layer cells of the embryo proper and extraembryonic tissues contribute in a coordinated manner to different aspects of epiboly movements. Developmental Dynamics, 2005. (c) 2005 Wiley-Liss, Inc.