Your browser version may not work well with NCBI's Web applications. More information here...
1: Dev Biol. 2007 Sep 15;309(2):358-72. Epub 2007 Jun 21.
Related Articles, Links
Click here to read Click here to read
Zebrafish Hoxb1a regulates multiple downstream genes including prickle1b.

Rohrschneider MR, Elsen GE, Prince VE.

The Committee on Developmental Biology, The University of Chicago, 1027 East 57th Street, Chicago, IL 60637, USA.

Despite 30 years of Hox gene study, we have a remarkably limited knowledge of the downstream target genes that Hox transcription factors regulate to confer regional identity. Here, we have used a microarray approach to identify genes that function downstream of a single vertebrate Hox gene, zebrafish hoxb1a. This gene plays a critical and conserved role in vertebrate hindbrain development, conferring identity to hindbrain rhombomere (r) 4. For example, zebrafish Hoxb1a, similar to mouse Hoxb1, is required for the migration of r4-derived facial branchiomotor neurons into the posterior hindbrain. We have screened microarrays carrying more than 16,000 expressed sequence tags (ESTs) for genes that are differentially regulated in normal versus Hoxb1a-deficient r4 tissue. Using this approach, we have identified both positively and negatively regulated candidate Hoxb1a target genes. We have used in situ hybridization to validate twelve positively regulated Hoxb1a targets. These downstream targets are expressed in a variety of subdomains within r4, with one gene, a novel prickle homolog (pk1b), expressed specifically within the facial branchiomotor neurons. Using morpholino knock-down and cell transplantation, we demonstrate that the Hoxb1a target Prickle1b functions cell-autonomously to control facial neuron migration, a single aspect of r4 identity.

Publication Types:
PMID: 17651720 [PubMed - indexed for MEDLINE]