11. Notably, theorists have shown that sequencing via exonuclease enzymes as described here is not feasible. 12. Yeast contains Rat1 and Xrn1 exonuclease . 13. By itself, the protein has 3'to 5'exonuclease activity and endonuclease activity. 14. Pol ? lacks 3'to 5'exonuclease activity and is a moderate fidelity polymerase. 15. Most contaminating DNA is degraded by the addition of a second single-strand specific exonuclease . 16. This process involves the exonuclease 's catching up to the pol II and terminating the transcription. 17. The ? subunit possesses DNA polymerase activity and the ? subunit is a 3-5 exonuclease . 18. This delay gives time for the DNA to be switched from the polymerase site to the exonuclease site. 19. The exonuclease activity of Rat1 degrades the RNA strand and halts transcriptions upon catching up to the polymerase. 20. The mutations that have been observed are in the regions that affect the exonuclease domain and polymerase domains.
