Transcription Elongation Factor A3 (TCEA3)

Transcription elongation factors in the SII class release RNA polymerase II from transcriptional arrest. TCEA1 binds to RNA polymerase II and stimulates nuclease activity during nucleotide misincorporation. Labhart and Morgan (1998) cloned a partial human cDNA encoding a third TFIIS isoform, TCEA3. Northern blot analysis of Xenopus tissues suggested that this isoform may have a restricted tissue expression. As transcription proceeds, RNA polymerase traverses the template strand and uses base pairing complementarity with the DNA template to create an RNA copy. Although RNA polymerase traverses the template strand from 3'=>5', the coding strand and newly-formed RNA can also be used as reference points, so transcription can be described as occurring 5'=>3'.