Mediator, known as a coactivator, can act in transcription initiation in an activator-independent manner in vivo.

08:00 EDT 7th July 2018 | BioPortfolio

Summary of "Mediator, known as a coactivator, can act in transcription initiation in an activator-independent manner in vivo."

Mediator is an evolutionarily conserved complex best known for its role as a coactivator responsible for transducing regulatory signals from DNA-bound activators to the basal RNA polymerase II (Pol II) machinery that initiates transcription from promoters of protein-encoding genes. By exploiting our in vivo activator-independent transcription assay in Saccharomyces cerevisiae, in combination with new temperature sensitive (ts) mutants of Med14 N-terminal half exhibiting widespread transcriptional defects, and existing ts mutants of Kin28 and Med17, we show that, in the absence of activator: (i) Mediator can associate with a promoter as a form devoid of the Cyclin-dependent kinase 8 (CDK8) module, and this association remains regulated by Kin28; (ii) Mediator can stimulate the assembly of the entire Pol II initiation machinery. Although the literature emphasizes the role of the interaction between activators and Mediator, together our results support the view that Mediator is able to act through a dual mechanism in vivo, activator-dependent but also activator-independent, therefore not always as a coactivator.


Journal Details

This article was published in the following journal.

Name: Biochimica et biophysica acta
ISSN: 0006-3002


DeepDyve research library

PubMed Articles [11443 Associated PubMed Articles listed on BioPortfolio]

Peroxisome proliferator-activated receptor γ coactivator family members competitively regulate hepatitis b virus biosynthesis.

Transcriptional coactivators represent critical components of the transcriptional pre-initiation complex and are required for efficient gene activation. Members of the peroxisome proliferator-activate...

Distinct Mechanisms of Transcription Initiation by RNA Polymerases I and II.

RNA polymerases I and II (Pol I and Pol II) are the eukaryotic enzymes that catalyze DNA-dependent synthesis of ribosomal RNA and messenger RNA, respectively. Recent work shows that the transcribing f...

Roles of Steroid Receptor Coactivator 3 in Host Defense Against Bacterial Pathogens.

Steroid receptor coactivator 3 (SRC-3) is a transcriptional coactivator that interacts with nuclear receptors such as the estrogen receptor and the androgen receptor and several other transcription fa...

Distribution of Initiation Times Reveals Mechanisms of Transcriptional Regulation in Single Cells.

Transcription is the dominant point of control of gene expression. Biochemical studies have revealed key molecular components of transcription and their interactions, but the dynamics of transcription...

Share and share alike: the role of Tra1 from the SAGA and NuA4 coactivator complexes.

SAGA and NuA4 are coactivator complexes required for transcription on chromatin. Although they contain different enzymatic and biochemical activities, both contain the large Tra1 subunit. Recent elect...

Clinical Trials [2561 Associated Clinical Trials listed on BioPortfolio]

A Drug-Drug Interaction Study of GK Activator (2) and Glyburide in Patients With Type 2 Diabetes.

This study will assess the potential pharmacodynamic and potential pharmacokinet ic interaction between GK Activator (2) and glyburide, in type 2 diabetes patien ts not adequately controll...

A Drug-Drug Interaction Study of GK Activator (2) and Simvastatin in Patients With Type 2 Diabetes.

This study will assess the potential pharmacokinetic interaction between GK Activator (2) and simvastatin, and the potential effect of simvastatin on the glucose-lowering effect of GK Acti...

Study of Targeted Therapy Using Transcription Activator-like Effector Nucleases in Cervical Precancerous Lesions

This is an open-label and triple cohort study of the safety and efficacy of T27 and T512 to possibly treat cervical intraepithelial neoplasia(CIN).

A Study to Evaluate the Long-Term Safety and Tolerability of GK Activator (2) in Patients With Type 2 Diabetes.

This study will evaluate the long-term safety and tolerability of GK Activator (2) at doses ranging from 25mg - 100mg po bid, administered alone or in combination with metformin, in patien...

A Dose-Titration Study of GK Activator (2) in Patients With Type 2 Diabetes.

This study will assess the efficacy, safety and tolerability of increasing doses of GK Activator (2) in patients with type 2 diabetes whose condition has not been optimally controlled with...

Medical and Biotech [MESH] Definitions

Artificial nucleases that cleave DNA at a defined distance from specific DNA sequences recognized by TRANSCRIPTION ACTIVATOR-LIKE EFFECTORS. They are composed of an endodeoxyribonuclease fused to DNA-binding domains of the transcription activator-like effectors.

The process that starts the transcription of an RNA molecule. It includes the assembly of the initiation complex and establishment of the start site.

A eukaryotic initiation factor that binds to 40S ribosomal subunits. Although initially considered a "non-essential" factor for eukaryotic transcription initiation, eukaryotic initiation factor-1 is now thought to play an important role in localizing RIBOSOMES at the initiation codon of MRNA.

A nuclear receptor coactivator with specificity for ESTROGEN RECEPTORS and PROGESTERONE RECEPTORS. It contains a histone acetyltransferase activity that may play a role in CHROMATIN REMODELING during the process of nuclear receptor-induced transcription. The coactivator has been found at elevated levels in certain HORMONE-DEPENDENT NEOPLASMS such as those found in BREAST CANCER.

The largest of the three prokaryotic initiation factors with a molecular size of approximately 80 kD. It functions in the transcription initiation process by promoting the binding of formylmethionine-tRNA to the P-site of the 30S ribosome and by preventing the incorrect binding of elongator tRNA to the translation initiation site.

Quick Search


DeepDyve research library

Relevant Topics

Bioinformatics is the application of computer software and hardware to the management of biological data to create useful information. Computers are used to gather, store, analyze and integrate biological and genetic information which can then be applied...

Polymerase Chain Reaction (PCR)
PCR (Polymerase Chain Reaction) uses the ability of DNA polymerase (enzymes that create DNA molecules by assembling nucleotides, the building blocks of DNA. These enzymes are essential to DNA replication and usually work in pairs to create two ident...

Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...

Searches Linking to this Article