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-22947
Mech Dev January 1, 1993; 40 (1-2): 73-84.

The structure and expression of the Xenopus Krox-20 gene: conserved and divergent patterns of expression in rhombomeres and neural crest.

Bradley LC , Snape A , Bhatt S , Wilkinson DG .


Abstract
Recent studies in the chick have indicated that rhombomeres (r) are segments that underlie the patterning of hindbrain nerves. These segments may also be important for the specification of branchial arch structures since alternating rhombomeres, r2, r4 and r6, each contribute crest to a specific arch. Krox-20 has been implicated in the segmental patterning of the hindbrain in the mouse by its expression prior to segment formation in alternating domains, which later correspond to r3 and r5. Here, we describe the sequence and developmental expression of the Xenopus Krox-20 gene, XKrox-20. Alternating domains of XKrox-20 expression appear in the early neurula, later correspond to r3 and r5, and persist until late tadpole stages. In contrast to this conserved spatial expression in rhombomeres, we find a pattern in the neural crest of Xenopus that appears different from that found in the mouse: expression occurs in crest that migrates from r5 into the third visceral arch. We speculate that this may reflect a distinct route of neural crest migration due to anatomical differences between these systems, rather than a difference in the site of origin of Krox-20-expressing crest.

PubMed ID: 8443108
Article link:

Genes referenced: egr2 tcirg1 tfap2a


Article Images: [+] show captions


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