This video provides a tutorial on the process of DNA transcription initiation and elongation in both prokaryotes and eukaryotes. There are three steps in DNA transcription, initiation, elongation and termination. In prokaryotes, RNA polymerase enzyme synthesizes all different forms of RNA. RNA polymerase enzyme contains core enzyme (alpha, beta, beta` and omega subunits) and sigma subunit. Holoenzyme binds to the pribnow box on the promoter region and initiate synthesizing small stretch of RNA. Following which the sigma subunit dissociates and core enzyme complete the synthesize of remainder of RNA strand. In eukaryotes, there three different RNA polymerase enzyme that synthesizes different forms of RNAs. In order for transcription to occur, chromatin loop is remodelled into euchromatin with the help of enzyme histone acetyltransferase. A specific protein called transcription factor IID binds to the core promoter, TATA box to initiate the transcription process. RNA polymerase II enzyme synthesizes pre-mRNA, which is then modified to generate mRNA strand via post-transcriptional modification.
The following topics are covered in this lesson,
1. Template/noncoding/antisense strand
2. Nontemplate/coding/sense strand
3. Transcription start site
4. RNA polymerase enzyme
5. Holoenzyme
6. Core enzyme
7. Transcription factors
8. Pribnow box
9. Oligonucleotides
10. Transcription bubble
11. Chromatin remodeling
12. Heterochromatin
13. Euchromatin
14. Histone acetyltransferase
15. Histone deacetylates
16. TATA box
17. CAAT box
18. Alpha-amanitin poisoning
14 июл 2024
