Cdx4 couples hox temporal collinear induction to spatial collinear expression

ISAAC SKROMNE; ALBERT HAYWARD; TRISTÁN AGÜERO

Congreso; 10th International Zebrafish Genetics and Development meeting; 2012

The Genetics Society of America

Accurate anterior-posterior patterning of the vertebrate axis is critically dependent on the deployment of a large family oftranscription factors, the hox genes, at precise developmental times and in specific embryonic domains. Spatiotemporal control of hoxgene expression is under several regulatory mechanisms. Key to hox gene regulation is a family of transcription factors, Cdx, shownto integrate numerous signaling inputs into coherent hox expression through poorly understood processes. To investigate Cdx function in hox gene regulation in neural and paraxial mesoderm tissue, we eliminated in embryos the activity of Cdx4. Loss of Cdx4 function caused a delay in hox gene induction and subsequently, a delay in the anterior spreading of hox expression domains in neural, but not paraxial mesoderm tissue. We conclude that in the nervous system Cdx4 initially functions to regulate temporal collinear induction of hox gene expression and subsequently, Cdx4 renders hox temporal collinear induction into spatial collinear expression.