Chapter 6 Regulation of Gene Expression in Eukaryotes
【教学目的】 本章要求学生掌握真核生物基因表达调控的基本 概念和理论，包括真核生物基因表达调控的多个层次， 顺式作用元件、反式作用因子及其相互关系，以及真核 基因不同水平的表达调控机制等。 【重点与难点】 1. 染色质重塑 2. 顺式作用元件、反式作用因子及其相互作用机制 3. 组蛋白密码 4. RNA干扰机制 【教学方法】 讲述式、多媒体教学、English Animation 【课时安排】 6-8课时
6.1 Multilevel Gene Regulation in Eukaryotes 6.2 Chromatin Remodeling 6.3 Transcriptional Regulation 6.4 Post-Transcriptional Regulation 6.5 Translational Regulation 6.6 Translational and Post-translational Regulation Summary
6.3 Transcriptional Regulation 1. Cis-Acting Element (1) What is cis-acting element? - DNA sequences close to a gene that are required for gene expression
(2) Features of Cis-Acting Elements ➢ contain short consensus sequences ➢ not fixed in location but usually within 200 bp ➢ usually upstream of the transcription start site ➢ a single element is usually sufficient for regulation ➢ many of them could bind specific proteins
TATA box GC box CAAT box Promoter Enhancer Silencer Insulator . Examples
(3) Types Cis-acting elements may be divided into two types: positve control elements → acivate transcription negaitve control elements → repress transcription
2. Major Types of Cis-Acting Element (1) Promoter -In genetics, a promoter is a region of DNA that facilitates the transcription of a particular gene. ❖ Core promoter in eukaryote: TATA-box, Initiator (Inr) in prokaryote: -10 region, Inr
❖ Proximal elements of promoter in prokaryote: -35 region in eukaryote: CAAT-box, GC-box UPE: upstream promoter element UAS: upstream activating sequence
