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Prediction and Validation of Gene Regulatory Elements Activated During Retinoic Acid Induced Embryonic Stem Cell Differentiation
Published on: June 21, 2016
A HOX complex, a repressor element and a 50 bp sequence confer regional specificity to a DPP-responsive enhancer
T Marty1, M A Vigano, C Ribeiro
1Abteilung Zellbiologie, Biozentrum, Universität Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
Development (Cambridge, England)
|August 30, 2001
Summary
Cell type-specific responses rely on integrating signaling pathways. This study reveals how a specific enhancer in Drosophila integrates DPP signaling and HOX proteins for precise gene expression during development.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- Cellular responses to extracellular signals are crucial for development and homeostasis.
- Mechanisms for integrating signaling pathways in a cell-type specific manner are not fully understood.
- Drosophila melanogaster serves as a model organism to study fundamental biological processes.
Purpose of the Study:
- To characterize an enhancer (lab550) regulated by DPP signaling and homeotic proteins.
- To elucidate the molecular mechanisms underlying cell-type specific gene expression.
- To understand how signaling inputs are integrated to generate specific developmental outcomes.
Main Methods:
- Detailed characterization of the lab550 enhancer and its mutants in Drosophila embryos.
- Analysis of enhancer activity in cultured cells.
- Deletion and point mutagenesis to dissect functional elements within the enhancer.
Main Results:
- The lab550 enhancer comprises two cooperating elements: a Homeotic Response Element (HOMRE) and a DPP Response Element (DPPRE).
- Neither HOMRE nor DPPRE alone can replicate the full expression pattern of lab550.
- A repressor element and an additional DNA element modulate DPPRE activity and are critical for HOMRE-DPPRE cooperation, linking DPP response to homeotic input.
Conclusions:
- The synergistic action of HOMRE and DPPRE, modulated by regulatory elements, generates segmentally restricted enhancer activity.
- This provides a mechanism for creating specific cellular responses to DPP signaling, guided by HOX protein complexes.
- The findings offer insights into the complex regulation of gene expression during embryonic development.
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