Related Experiment Video
Updated: Jul 15, 2026
09:07
Detecting the Ligand-binding Domain Dimerization Activity of Estrogen Receptor Alpha Using the Mammalian Two-Hybrid Assay
Published on: December 19, 2018
Reprogramming of the SWI/SNF complex for co-activation or co-repression in prohibitin-mediated estrogen receptor
B Zhang1, K J Chambers, D V Faller
1Cancer Research Center, Boston University School of Medicine, Boston, MA 02118, USA.
Oncogene
|May 9, 2007
Summary
The SWI/SNF complex
Area of Science:
- Molecular Biology
- Gene Regulation
- Chromatin Remodeling
Background:
- The SWI/SNF complex is known to regulate gene transcription.
- Brg1 and Brm, key SWI/SNF components, can function as co-repressors for E2F-mediated repression and other promoters.
Purpose of the Study:
- To investigate how Brg1 and Brm switch between co-activator and co-repressor roles.
- To understand the role of ligand-directed interactions in SWI/SNF complex function.
Main Methods:
- Investigated the interactions of Brg1 and Brm with other proteins.
- Analyzed the effect of ligand binding on SWI/SNF complex composition and function.
- Examined transcriptional regulation at specific promoters.
Main Results:
- Brg1 and Brm can switch between transcriptional activation and repression at the same promoter.
- This switch is mediated by differential coordination with proteins like BAF155, BAF170, HDAC1, p300, and prohibitin.
- Ligand binding dictates the functional mode of the SWI/SNF complex.
Conclusions:
- The SWI/SNF complex's function as a co-activator or co-repressor is context-dependent.
- Ligand-directed reprogramming allows the SWI/SNF complex to modulate transcription dynamically.
- This highlights a novel mechanism for fine-tuning gene expression.
Related Concept Videos
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
01:31Transducer Mechanism: Nuclear Receptors
Nuclear receptors, or NRs, are unique transcription factors that regulate gene transcription and affect the cellular pathways involved in reproduction, development, or metabolism. Their ability to be stimulated by small lipophilic ligands and control vital cellular processes makes them ideal drug targets. Nearly 10-15% of currently prescribed drugs target these receptors.
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
01:14Introduction to Nuclear Reprogramming
Nuclear reprogramming is the process of switching gene expression of one cell type to that of another cell type, usually from a differentiated cell state to an undifferentiated cell state. Differentiation occurs during processes such as development and morphogenesis, tissue regeneration, and malignancy. Cells can also be artificially induced to reprogram their gene expression by techniques such as nuclear transfer, induced pluripotency, and cell fusion. Such techniques have many applications in...