Addition of the third nucleotide on the nascent transcript

Stable Identifier
R-HSA-75850
Type
Reaction [BlackBoxEvent]
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.

Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
helicase activity of TFIIH [nucleoplasm]
Physical Entity
Activity
Title
DNA-directed 5'-3' RNA polymerase activity of RNA Polymerase II (unphosphorylated):TFIIF complex [nucleoplasm]
Physical Entity
Activity
Orthologous Events