GENE 3200 Study Guide - Midterm Guide: Heterochromatin, Deoxyribonuclease, Methyl Group
Document Summary
Basic lo: describe how dna is organized in chromatin, heterochromatin and euchromatin, open promoters- tf and rna pol can access dna (euchromatin, closed/covered promoters- nucleosomes block tfs & rna pol access to dna. Transcription off until nucleosome moved (heterochromatin: distinguish between heterochromatin and euchromatin, eukromatin would be loosely packaged, addition of acetyl groups, dna will be more loosely and more likely to be transcribed because the promoter is more available. A lot of methyl groups will often recruited histone deacetyles, when you remove the acetyl groups, forms heterochromatin. When heterochromatin, expression of gene is less likely to be expressed: cpg isands are symmetrical, histone acetylation, adding an acetyl group, decreases the ability to interact with dna, polar charge, more neutral. Histone with hold on to the dna more loosely. If this modification is being added to lots of histones, you can change the structure: different modifications of histones will have different affects on genes.
