Ch. 17 - Transcriptional Regulation in Eukaryotes

Klug - Concepts of Genetics 12th Edition

Klug12th EditionConcepts of GeneticsISBN: 9780135564776당신이 사용하는 게 아니라요?교과서 변경

Klug 12th Edition

Ch. 17 - Transcriptional Regulation in Eukaryotes

문제 17

17장, 문제 17

Explain the features of the Initiator (Inr) elements, BREs, DPEs, and MTEs of focused promoters.

검증된 단계별 안내

Start by defining what a focused promoter is: a promoter type where transcription initiates at a single or a few closely spaced start sites, often found in genes with regulated expression.

Explain the Initiator (Inr) element: it is a core promoter sequence that overlaps the transcription start site (TSS) and helps direct the accurate initiation of transcription by RNA polymerase II. Typically, it has a consensus sequence around the +1 position.

Describe the BRE (TFIIB Recognition Element): this element is located immediately upstream or downstream of the TATA box and serves as a binding site for the transcription factor TFIIB, which helps recruit RNA polymerase II to the promoter.

Discuss the DPE (Downstream Promoter Element): found downstream of the TSS (around +28 to +32), the DPE works together with the Inr to facilitate transcription initiation, especially in promoters lacking a TATA box.

Explain the MTE (Motif Ten Element): located downstream of the TSS (around +18 to +27), the MTE cooperates with the Inr and DPE to enhance transcription efficiency by providing additional binding sites for transcription factors.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Initiator (Inr) Element

The Initiator (Inr) is a core promoter element located around the transcription start site (TSS). It helps direct RNA polymerase II to the correct initiation point, often compensating for the absence of a TATA box. The Inr sequence is typically rich in pyrimidines and purines, facilitating precise transcription initiation.

TFIIB Recognition Elements (BREs)

BREs are short DNA sequences found immediately upstream (BREu) or downstream (BREd) of the TATA box in focused promoters. They serve as binding sites for the general transcription factor TFIIB, enhancing the stability and specificity of the pre-initiation complex formation, thus influencing transcription efficiency.

Downstream Promoter Elements (DPEs) and Motif Ten Elements (MTEs)

DPEs and MTEs are core promoter elements located downstream of the TSS, typically between +28 to +32 for DPE and +18 to +27 for MTE. They function in promoters lacking a TATA box by interacting with transcription factors like TFIID, aiding in the recruitment of RNA polymerase II and promoting accurate transcription initiation.

관련 실천

교과서 질문

DNA supercoiling, which occurs when coiling tension is generated ahead of the replication fork, is relieved by DNA gyrase. Supercoiling may also be involved in transcription regulation. Researchers discovered that enhancers operating over a long distance (2500 bp) are dependent on DNA supercoiling, while enhancers operating over shorter distances (110 bp) are not so dependent [Liu et al. (2001). Proc. Natl. Acad. Sci. USA 98:14,883–14,888]. Using a diagram, suggest a way in which supercoiling may positively influence enhancer activity over long distances.

1097

views

교과서 질문

Research indicates that promoters may fall into one of two classes: focused or dispersed. How do these classes differ, and which genes tend to be associated with each?

526

views

교과서 질문

Compare the control of gene regulation in eukaryotes and bacteria at the level of initiation of transcription. How do the regulatory mechanisms work? What are the similarities and differences in these two types of organisms in terms of the specific components of the regulatory mechanisms?

848

views

교과서 질문

Many promoter regions contain CAAT boxes containing consensus sequences CAAT or CCAAT approximately 70 to 80 bases upstream from the transcription start site. How might one determine the influence of CAAT boxes on the transcription rate of a given gene?

891

views

교과서 질문

How do the ENCODE data vastly help determine which enhancers regulate which genes?

579

views

교과서 질문

Many transcriptional activators are proteins with a DNA-binding domain (DBD) and an activation domain (AD). Explain how each domain contributes to transcriptional initiation. Would you expect repressors to also have each of these domains?

735

views