Format

Send to

Choose Destination
PLoS Genet. 2016 Apr 8;12(4):e1005981. doi: 10.1371/journal.pgen.1005981. eCollection 2016 Apr.

A Hox Transcription Factor Collective Binds a Highly Conserved Distal-less cis-Regulatory Module to Generate Robust Transcriptional Outcomes.

Author information

1
Division of Developmental Biology, Cincinnati Children's Hospital, Cincinnati, Ohio, United States of America.
2
Graduate Program in Molecular and Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio, United States of America.

Abstract

cis-regulatory modules (CRMs) generate precise expression patterns by integrating numerous transcription factors (TFs). Surprisingly, CRMs that control essential gene patterns can differ greatly in conservation, suggesting distinct constraints on TF binding sites. Here, we show that a highly conserved Distal-less regulatory element (DCRE) that controls gene expression in leg precursor cells recruits multiple Hox, Extradenticle (Exd) and Homothorax (Hth) complexes to mediate dual outputs: thoracic activation and abdominal repression. Using reporter assays, we found that abdominal repression is particularly robust, as neither individual binding site mutations nor a DNA binding deficient Hth protein abolished cooperative DNA binding and in vivo repression. Moreover, a re-engineered DCRE containing a distinct configuration of Hox, Exd, and Hth sites also mediated abdominal Hox repression. However, the re-engineered DCRE failed to perform additional segment-specific functions such as thoracic activation. These findings are consistent with two emerging concepts in gene regulation: First, the abdominal Hox/Exd/Hth factors utilize protein-protein and protein-DNA interactions to form repression complexes on flexible combinations of sites, consistent with the TF collective model of CRM organization. Second, the conserved DCRE mediates multiple cell-type specific outputs, consistent with recent findings that pleiotropic CRMs are associated with conserved TF binding and added evolutionary constraints.

PMID:
27058369
PMCID:
PMC4825978
DOI:
10.1371/journal.pgen.1005981
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center