Dissecting the pre-placodal transcriptome to reveal presumptive direct targets of Six1 and Eya1 in cranial placodes

Abstract
Data availability
Article and author information
Metrics

Abstract

The pre-placodal ectoderm, marked by the expression of the transcription factor Six1 and its co-activator Eya1, develops into placodes and ultimately into many cranial sensory organs and ganglia. Using RNA-Seq in Xenopus laevis we screened for presumptive direct placodal target genes of Six1 and Eya1 by overexpressing hormone-inducible constructs of Six1 and Eya1 in pre-placodal explants, and blocking protein synthesis before hormone-inducing nuclear translocation of Six1 or Eya1. Comparing the transcriptome of explants with non-induced controls, we identified hundreds of novel Six1/Eya1 target genes with potentially important roles for placode development. Loss-of-function studies confirmed that target genes encoding known transcriptional regulators of progenitor fates (e.g. Sox2, Hes8) and neuronal/sensory differentiation (e.g. Ngn1, Atoh1, Pou4f1, Gfi1) require Six1 and Eya1 for their placodal expression. Our findings provide insights into the gene regulatory network regulating placodal neurogenesis downstream of Six1 and Eya1 suggesting new avenues of research into placode development and disease.

Data availability

The following data sets were generated

1. Riddiford N
2. Schlosser G
(2016) PRJNA317049
Publicly available at the NCBI BioProject database (accession no: PRJNA317049).

http://www.ncbi.nlm.nih.gov/bioproject?LinkName=biosample_bioproject&from_uid=4640079

Article and author information

Author details

Nick Riddiford

School of Natural Sciences, National University of Ireland, Galway, Ireland

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0002-4739-4233
Gerhard Schlosser

School of Natural Sciences, National University of Ireland, Galway, Ireland

For correspondence
gerhard.schlosser@nuigalway.ie

Competing interests
The authors declare that no competing interests exist.

Funding

Science Foundation Ireland (11/RFP/EOB/3168)

Gerhard Schlosser

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All animal experiments were performed in full accordance with Irish and European legislation, were approved by the NUI Galway Animal Care Research Ethics Committee (ACREC, 003/10) and were covered under the animal license (Cruelty to Animals Act, 1876) B100/4291 to G. Schlosser.

Copyright

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.