Exam #5 BIO 305

FML

Second Level packaging

30-nm fiber (nucleosome coiled into thicker structure)

Eukaryotic default state

restrictive

Prokaryotic default state

permissive

Restrictive nature of Eukaryotic DNA

contributes to silencing genes

Mechanisms for Eukaryotic gene regulation (6)

1. Transcription initiation

2. RNA processing

3. RNA transport

4. RNA stability

5. Translation efficiency

6. Protein activation/modification

Primary form of gene regulation

Transcription

Cis-acting elements for regulation of transcription by poly II

Promoter, Promoter proximal site, Enhancers

Trans-acting elements for regulation of transcription by poly II

Basal(general) TFs, Regulatory TFs

Class of trans-acting that does NOT bind directly to DNA

Mediator, Coactivaters, Corepressors

Euchromatin

loose, active

Heterochromatin

tightly packed, inactive

What is the role of Cis-regulatory modules?

Provide binding sites for regulatory transcription factors

Group of enzymes that add Me to chromatin?

Chromatin Writers

Group of enzymes that remove Me from chromatin?

Chromatin Erasers

Group of enzymes that identify methylation?

Chromatin readers