Transcription elongation factor A protein 1 (TCEA1)

Needed for efficient RNA polymerase II transcription elongation past template-encoded arresting sites. The arresting sites in DNA have the property of trapping a certain fraction of elongating RNA polymerases that pass through, resulting in locked ternary complexes.

Cleavage of the nascent transcript by S-II allows the resumption of elongation from the new 3'-terminus. .