Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-9612
Genesis February 1, 2001; 29 (2): 78-90.

xPitx1 plays a role in specifying cement gland and head during early Xenopus development.

Chang W , KhosrowShahian F , Chang R , Crawford MJ .


Abstract
Xenopus Pitx1 is a homeobox gene whose family members are structurally and functionally conserved in organisms as diverse as Drosophila, chick, mouse, human, and frog. Present as a maternal transcript, the gene is zygotically expressed during gastrulation in a dorsal streak of cells. This streak restricts to a small circular domain underlying the center of presumptive neural plate. Shortly thereafter, a crescent of expression develops at the border of anterior neural ectoderm, and as the central plate domain diminishes, the crescent coalesces to define the presumptive cement gland. Expression remains high throughout cement gland development, and subsequently expands to include ectodermal cells involved in stomodeal invagination. During early organogenesis, expression ensues in developing eye, posterior lateral mesoderm, and first branchial arch derivatives. Ectopic expression of xPitx1 causes head deformities including enlarged cement gland, ectopic cement glands, and posterior deformities or, in extreme cases, inhibition of recognizable structures posterior to the cement gland. Expression of markers such as XCG-1, xOtx2, xPax6, neuralbeta tubulin, and xTwist suggest that increases in cement gland and lower mandibular size are likely at the expense of other head tissues. Paradoxically, overexpression is sufficient to partially rescue embryos that are axially perturbed by ultraviolet irradiation or retinoic acid administration. Ectopic expression of xPitx1 in ectodermal explants directly promotes cement gland development as there was no evidence that mesodermal or neural tissue was present in explants.

PubMed ID: 11170348
Article link: Genesis

Genes referenced: eef1a1 frzb2 fubp1 muc2 otx2 pax6 pitx1 tbxt tubb2b twist1


Article Images: [+] show captions


Xenbase: The Xenopus Model Organism Knowledgebase.
Version: 4.14.0
Major funding for Xenbase is provided by grant P41 HD064556