Transcription Notes

Transcription Notes - chromosomes. RNA processing None...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Transcription (General) Initiation: 1) Binding of the RNA polymerase to the promoter sequence. 2) Denaturation of the double-helix 3) RNA polymerase catalyses the creation of the phosphodiester bonds between the first two RNucleo. Elongation: 1) Addition of RNucleos from 5’ to 3’. 2) Continued denaturation of DNA. (Transcription bubble always around 14 nucleo long) 3) Phosphodiester linkages form. Termination: 1) RNA polymerase stops at a stop site sequence. 2) Release of completed RNA strand. 3) RNA polymerase dissociates with the DNA template strand. Prokaryotes: Eukaryotes RNA Polymerase Simple enzyme (4 or 5 subunits) Complex, 3 RNA Polymerases (I, II, III) Transcription Initiation Must be assisted by sigma factor. RNA Polymerase assisted by general transcription factors. These proteins help initiate transcription. Gene organization Operon, few non-coding gaps, generally no introns, co-regulation Introns and exons. Genes involved in same function are on different
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: chromosomes. RNA processing None Introns, 5’ cap, 3’ Poly A Post-transcriptional regulation miRNA, siRNA Cytoplasmic polyadenylation (unique), miRNA, siRNA mRNA Unstable, decays in few minutes Stable and can last hours, days or months or a lifetime. Sigma factors Needs sigma factors (70 and 54) to help RNA Polymerase bind No sigma factors. RNA polymerase subunits has similar functions. Translation Same time as transcription Separate processes. mRNA must be exported before translation can occur Ribosomes 70S, 3 different rRNA molecules 80S, 4 different rRNA molecules 1) Tatabox binding protein binds to Tatabox. 2) TFIIB binds to DNA and TBP to secure both. 3) TFIIF binds to RNA Polymerase II and both bind to DNA just downstream of Tatabox as TBP recognizes RNA polymerase. 4) TFIIE binds. 5) TFIIH binds. Its subunit, kinase phosphorylates the CTD, promoting elongation. 6) After initiation, everything dissociated except TBP....
View Full Document

This note was uploaded on 09/18/2011 for the course SCIENCE biol 200 taught by Professor Bureau during the Spring '11 term at McGill.

Page1 / 2

Transcription Notes - chromosomes. RNA processing None...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online