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-6971
Dev Biol July 1, 2002; 247 (1): 137-48.

Distinct patterns of downstream target activation are specified by the helix-loop-helix domain of proneural basic helix-loop-helix transcription factors.

Talikka M , Perez SE , Zimmerman K .


Abstract
Both gain- and loss-of-function analyses indicate that proneural basic/helix-loop-helix (bHLH) proteins direct not only general aspects of neuronal differentiation but also specific aspects of neuronal identity within neural progenitors. In order to better understand the function of this family of transcription factors, we have used hormone-inducible fusion constructs to assay temporal patterns of downstream target regulation in response to proneural bHLH overexpression. In these studies, we have compared two distantly related Xenopus proneural bHLH genes, Xash1 and XNgnr1. Our findings indicate that both Xash1 and XNgnr1 induce expression of the general neuronal differentiation marker, N-tubulin, with a similar time course in animal cap progenitor populations. In contrast, these genes each induce distinct patterns of early downstream target expression. Both genes induce expression of the HLH-containing gene, Xcoe2, at early time points, but only XNgnr1 induces early expression of the bHLH genes, Xath3 and XNeuroD. Structure:function analyses indicate that the distinct pattern of XNgnr1-induced downstream target activation is linked to the XNgnr1 HLH domain, demonstrating a novel role for this domain in mediating the differential function of individual members of the proneural bHLH gene family.

PubMed ID: 12074558
Article link: Dev Biol
Grant support: [+]

Species referenced: Xenopus laevis
Genes referenced: acta4 actl6a ascl1 ebf2 nefm neurod1 neurod4 neurog2 nkx1-2 tbxt tubb2b


Article Images: [+] show captions