BIOL 300 Lecture Notes - Lecture 7: Heterochromatin, Dna Annotation, Histone H2B
15 Dec 2012
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Document Summary
Establishment of global chromatin environments: chromatin is not the same everywhere in the chromosome: heterochromatin is silent while euchromatin is active, this requires establishing boundary elements to separate the types of chromatin. These are elements which prevents a particular state of chromatin to spread to regions where they don"t belong. Chromatin states are able to spread to different regions through specific mechanisms: telomere centromere function: Chromatin is packed here in particular ways in order to provide unique mechanical properties (e. g. pulling apart in anaphase by linking to nuclear envelope proteins) Orchestrations of dna based biological tasks: regulation of gene expression in euchromatin, requires delivery of chromatin modifying enzymes by dna bound transcription factors. N-terminal acetylation is clearly involved in the regulation of gene expression. There are two protein domains which specifically interact with covalently modified histones, each with their own specific recognition site:
