2Alecture+22+big+color

2Alecture+22+big+color - Lecture 22 Eukaryo/c gene...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
5/23/11 Lecture’22: Eukaryo/c’gene’regula/on General±Core’transcrip/on’factors Transcrip/onal’ac/va/on’factors’(and repressors)’consist’of’2’to’3’dis/nct’ domains DNA’binding’and’ac/va/on,’and (some/mes)’signal-sensing Chap:’16.3,’16.4 A’promoter’is …. a.A’DNA’sequence b.An’RNA’sequence c. A’protein d.A’micro’RNA
Background image of page 1

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

View Full Document Right Arrow Icon
5/23/11 A’promoter’includes a.A’site’that’binds’mRNA b.A’site’that’binds’RNA’polymerase c. A’site’that’binds’regulatory’factors d.A’site’that’binds’ ribosomes Possible’modes’of’Transcrip/onal’control Nega/ve’control:’Turning’oF’transcrip/on’by’blocking’access to’the’promoter Promoter Regulatory Region (operator) transcript In bacteria, its easy for RNA polymerase to locate promoters
Background image of page 2
5/23/11 Nega/ve’control:’Example’from’ lac’operon Promoter Regulatory Region (operator) Genes for lactose import and digestion lacI Regulatory protein (Active Lac Repressor) Nega/ve’control:’Blocking’access’to’the’gene Promoter Regulatory Region (operator) lacI Regulatory protein (Active Repressor) RNA pol NO TRANSCRIPTION of lacZ,Y, A ???
Background image of page 3

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

View Full Document Right Arrow Icon
5/23/11 Nega/ve’control:’Blocking’access’to’the’gene Promoter Regulatory Region (operator) lacI Regulatory protein (Active Repressor) RNA pol Coded for by a gene elsewhere in the DNA!!! How’can’you’turn’the’gene’on? Promoter Regulatory Region (operator) lacI Regulatory protein (Active Repressor) RNA pol ???
Background image of page 4
5/23/11 How’ might you’turn’the’gene’on? A. Mutate’the’operator B. Mutate’the’repressor C. Degrade’(=’destroy)’the’repressor D. Inac/vate’the’repressor E. Switch’of’the’gene’For’the’repressor Promoter Regulatory Region (operator) repressor How’could’the’gene’be’turned ’on ? Promoter Regulatory protein (Repressor) Small inducer molecule (lactose) Which induces what, exactly? A.Expression of the lacI gene B.Activity of the lacI protein C.Expression of the lac Z, Y, and A genes
Background image of page 5

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

View Full Document Right Arrow Icon
5/23/11 How’could’the’gene’be’turned ’on ? Promoter Regulatory protein (Repressor) Small inducer molecule (lactose) How does it induce anything? A.By inhibiting a repressor B.By activating a repressor C.By activating an activator D.By inhibiting an activator How’could’the’gene’be’turned’on? Promoter Regulatory protein (Inactive Repressor) RNA pol Change in shape of Repressor (allosteric inhibition)
Background image of page 6
5/23/11 How’could’the’gene’be’turned’on? Promoter RNA pol Change in shape of Repressor (allosteric inhibition) Gene is transcribed In’eukaryotes,’areas’of’ac/ve’chroma/n’have’to’be’maintained- groomed-’by’proteins’like’ HATs’ (histone’ acetyl’ transferases).
Background image of page 7

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

View Full Document Right Arrow Icon
5/23/11 Heterochromatin - methylated DNA, particular methylated lysines Euchromatin - Acetylated and phosphorylated nucleosomes, different methylated lysines Eukaryotic DNA is wound around nucleosomes- this results in greater or lesser
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 20

2Alecture+22+big+color - Lecture 22 Eukaryo/c gene...

This preview shows document pages 1 - 9. Sign up to view the full document.

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