What is the role of RNA polymerase II?

Eukaryotic RNA polymerase II (pol II) is a 12-subunit DNA-dependent RNA polymerase that is responsible for transcribing nuclear genes encoding messenger RNAs and several small nuclear RNAs (1).

What causes transcription termination?

Transcription termination is caused by the destabilization and/or a conformational change of the Pol II EC after transcribing the poly(A) site. Release of antitermination factors (left) or recruitment of termination factors (right) triggers dissociation from template DNA.

What initiates termination?

Termination occurs when an employer or an employee ends an employee’s employment with a particular employer. When termination is initiated by the employer, it is usually involuntary although, under some circumstances, the employee and the employer may mutually agree to end their employment relationship.

What happens to RNA polymerase II after it?

What happens to RNA polymerase II after it has completed transcription of a gene? The enzyme is free to transcribe other genes in the cell. the DNA, pairing up RNA nucleotides with their DNA complements— adding nucleotides to the end of the growing RNA molecule.

What does RNA polymerase III do?

RNA polymerase III (Pol III) transcribes various small stable RNAs that are essential in multiple cellular pathways, including pre-mRNA splicing (U6 snRNA) and protein synthesis (5S rRNA, tRNAs)2.

What causes the termination of transcription in prokaryotes?

Termination in Prokaryotes Rho-dependent termination is controlled by the rho protein, which tracks along behind the polymerase on the growing mRNA chain. The result is a stable hairpin that causes the polymerase to stall as soon as it begins to transcribe a region rich in A–T nucleotides.

What is the termination state of RNA polymerase II?

Termination: Pol II ceases RNA synthesis and becomes termination-prone (indicated by its change in colour from green to yellow), and both Pol II and the nascent RNA are released from the template. As shown, destabilization of the RNA–DNA hybrid in the Pol II active site is likely to be a key feature in termination.

How does RNA polymerase II (Pol II) work?

RNA polymerase II (Pol II) transcribes hundreds of thousands of transcription units – a reaction always brought to a close by its termination. Because Pol II transcribes multiple gene types, its termination occurs in a variety of ways, with the polymerase being responsive to different inputs.

Why does Pol II terminate at the end of genes?

Because Pol II transcribes multiple gene types, its termination occurs in a variety of ways, with the polymerase being responsive to different inputs. Moreover, it is not just a default process occurring at the end of genes.

How does the Nusa termination factor interact with RNA polymerase?

Findings from this study show that interaction of the NusA termination factor with regions of bacterial RNA polymerase near the RNA exit channel (such as the β-flap and β′-dock) stimulates pausing and release. Toulokhonov, I., Artsimovitch, I. & Landick, R. Allosteric control of RNA polymerase by a site that contacts nascent RNA hairpins.