Eukaryotic Transcription Overview

These flashcards cover the key concepts of eukaryotic transcription, including major elements involved in the process, regulatory mechanisms, and transcription machinery.

Eukaryotic Transcription

The process by which eukaryotic cells transcribe DNA into RNA, involving numerous regulatory elements and complex machinery.

Pre-initiation Complex

A formation consisting of RNA polymerase II and general transcription factors that is crucial for the start of transcription at the promoter.

Cis-acting elements

Regulatory DNA sequences that are located near the gene they regulate, such as promoters and enhancers.

Trans-acting factors

Proteins such as transcription factors that are produced from elsewhere in the genome and can regulate genes at distant locations.

RNA polymerase II

The enzyme responsible for synthesizing mRNA in eukaryotic cells.

General transcription factors

Proteins that assist RNA polymerase II in recognizing the promoter and initiating transcription.

Enhancers

Long-range regulatory elements that increase the likelihood of transcription when bound by specific transcription factors.

Silencers

DNA elements that can inhibit transcription when bound by specific factors, reducing gene expression.

Mediator

A multi-subunit complex that conveys signals from transcriptional activators to RNA polymerase II.

Transcription initiation

The first step in the transcription process where RNA polymerase II and transcription factors assemble at the promoter to start RNA synthesis.

Transcription elongation

The phase following initiation where RNA polymerase II synthesizes the RNA transcript by adding nucleotides to the growing chain.

Transcription termination

The process that concludes transcription, leading to the release of the newly synthesized RNA molecule; mechanisms in eukaryotes are less understood.

Chromatin insulators

Elements that function to block enhancer activity toward adjacent genes, establishing boundaries between regions of active and inactive chromatin.