Reactome: A Curated Pathway Database

Addition of the third nucleotide on the nascent transcript

Stable Identifier
R-HSA-75850
Type
Reaction
Species
Homo sapiens
Compartment
Locations in the PathwayBrowser
Summation

Formation of the second phosphodiester bond creates a 3-nt product. This short transcript is still loosely associated with the RNA polymerase II initiation complex and can dissociate to yield abortive products, which are not further extended. The transcription complex still requires continued ATP-hydrolysis by TFIIH and remains sensitive to single-stranded oligo-nucleotide inhibition.

The open region (‚??transcription bubble‚??) expands concomitant with the site of RNA-extension. In this case this region spans positions -9 to +3.

Literature References
Participants
Participant Of
This entity is regulated by:
Title Physical Entity Activity
DNA-directed RNA polymerase activity of RNA Polymerase II (unphosphorylated):TFIIF complex [nucleoplasm] RNA Polymerase II (unphosphorylated):TFIIF complex [nucleoplasm] DNA-directed RNA polymerase activity (0003899)
helicase activity of TFIIH [nucleoplasm] TFIIH [nucleoplasm] helicase activity (0004386)
Orthologous Events