Lect18.RNA.part1

Lect18.RNA.part1 - LECTURE 17: RNA TRANSCRIPTION,...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
LECTURE 17: RNA TRANSCRIPTION, PROCESSING, TURNOVER Levels of specific messenger RNAs can differ in different types of cells and at different times in the same cell. Control of RNA abundance can be at the level of transcription initiation, transcription elongation, processing or degradation. RNA control mechanisms are more complex and varied in eukaryotes than in prokaryotes.
Background image of page 1

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

View Full DocumentRight Arrow Icon
RNA POLYMERASE Mediates transcription of RNA from a double-stranded DNA template Does not require primer Transcription is always 5’ --> 3’ direction, with each base addition using reaction RNA n + NTP --> RNA n+1 + PP i Transcription inititation mediated by proteins that bind to specific promoter sequence elements. The promoter binding proteins recruit RNA polymerase to the initiation site. RNA polymerases show evolutionary conservation between prokaryotes and eukaryotes, accounting for many similarities in transcription mechanism But there are substantial differences in transcription initiation, termination, and post-transcriptional RNA processing between pro- and eukaryotes
Background image of page 2
PROKARYOTIC TRANSCRIPTION INITIATION Prokaryotic promoters have elements near position -10 and -35 that bind to the σ initiation factor. Promoter elements have been physically mapped by DNA footprinting . Footprinting Technique
Background image of page 3

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

View Full DocumentRight Arrow Icon
ELONGATION PROCEEDS IN A MOVING TRANSCRIPTION BUBBLE
Background image of page 4
TRANSCRIPTION - TRANSLATION COUPLING IN PROKARYOTES Prokaryotic mRNA does not require processing nor cell compartment
Background image of page 5

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

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/14/2012 for the course BIO 710L taught by Professor Goldfarb during the Fall '10 term at Iowa State.

Page1 / 19

Lect18.RNA.part1 - LECTURE 17: RNA TRANSCRIPTION,...

This preview shows document pages 1 - 6. Sign up to view the full document.

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