Term
| Name the6 mechanism by which eukaryotic gene regulatory proteins can repress transcription: |
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Definition
1.Competitive DNA binding
2.Masking of an activating surface
3.Direct interaction with the general transcription factors
4.Recruitment of chromatin remodeling complexes
5.Recruitment of histone deacetylases
6.Recruitment of histone methyl transferases
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Term
Functions of the LCR in Beta-Globin expression |
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Definition
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•Proteins binding to the HS in the LCR mediate the formation ofmodified chromatin domains and an accessible LCR holocomplex
•If the stem cell commits to another lineage, the entire LCR andglobin locus is packed into heterochromatin
•If the stem cell commits to the erythroid lineage,
erythroid-specific (and other) factors bind to the globin locus,further unfold the chromatin structure and bring the LCR andthe b-globin promoter in close proximity
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Term
DNA methylation can affect gene expression in two ways..... |
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Definition
1.Direct interference of methyl-CpG with the DNA binding of gene regulatory proteins
2. Proteins which directly bind methylated CpGs independent of surrounding sequence
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Term
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Definition
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1) MECP2 functions as DNA methylation dependent transcriptional repressor.
2) MECP2 recruits histone deacetylase machinery to remodel chromatin
3)Do not see generalized changes in gene expression - thus MeCP2 has specific ranscription repression targets.
4) If mutated, causes Rett syndrome (X-LINKED DOMINANT, MALE LETHAL)
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Term
What is the result of mutations in the Has barrier sequence found in the beta-globin locus LCR? |
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Definition
- Thalassemia
- Active HS4 keeps heterochromatin from coming in and blocking transcription
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