Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 15, Problem 13CONQ
Transcription factors such as the glucocorticoid receptor and the CREB protein form homodimers and activate transcription. Other transcription factors form heterodimers. For example, a transcription factor known as myogenic bHLH forms a heterodimer with a protein called the E protein. This heterodimer activates the transcription of genes that promote muscle cell differentiation. However, when myogenic bHLH forms a heterodimer with a protein called the Id protein, transcriptional activation does not occur. (Note: Id stands for “Inhibitor of differentiation.”) Which of the following possibilities best explains this observation? Only one possibility is correct.
| Myogenic bHLH | E Protein | Id Protein | |
| Possibility 1 | |||
| DNA-binding domain: | Yes | No | No |
| Leucine zipper: | Yes | No | Yes |
| Possibility 2 | |||
| DNA-binding domain: | Yes | Yes | No |
| Leucine zipper: | Yes | Yes | Yes |
| Possibility 3 | |||
| DNA-binding domain: | Yes | No | Yes |
| Leucine zipper: | Yes | No | No |
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Chapter 15 Solutions
Genetics: Analysis and Principles
Ch. 15.1 - 1. Combinatorial control refers to the phenomenon...Ch. 15.1 - 2. A regulatory transcription factor protein...Ch. 15.1 - 3. A bidirectional enhancer has the following...Ch. 15.1 - 4. Regulatory transcription factors can be...Ch. 15.2 - 1. A chromatin-remodeling complex may
a. change...Ch. 15.2 - Prob. 2COMQCh. 15.2 - 3. Which of the following characteristics is...Ch. 15.2 - 4. Transcriptional activation of eukaryotic genes...Ch. 15.3 - How can methylation affect transcription? a. It...Ch. 15.3 - 2. The process in which completely unmethylated...
Ch. 15.4 - Prob. 1COMQCh. 15.5 - The overall goal of the ENCODE Project is a. to...Ch. 15.6 - The binding of iron regulatory protein (IRP) to...Ch. 15 - Discuss the common points of control in eukaryotic...Ch. 15 - 2. Discuss the structure and function of...Ch. 15 - 3. What is meant by the term transcription factor...Ch. 15 - What are the functions of transcriptional...Ch. 15 - 5. Is each of the following statements true or...Ch. 15 - 6. Transcription factors usually contain one or...Ch. 15 - Prob. 7CONQCh. 15 - Prob. 8CONQCh. 15 - 9. Let’s suppose a mutation in the glucocorticoid...Ch. 15 - Prob. 10CONQCh. 15 - Prob. 11CONQCh. 15 - Prob. 12CONQCh. 15 - 13. Transcription factors such as the...Ch. 15 - An enhancer, located upstream from a gene, has the...Ch. 15 - 15. The DNA-binding domain of each CREB protein...Ch. 15 - The gene that encodes the enzyme called tyrosine...Ch. 15 - Prob. 17CONQCh. 15 - 18. What is a histone variant?
Ch. 15 - Prob. 19CONQCh. 15 - 20. What is meant by the term histone code? With...Ch. 15 - Prob. 21CONQCh. 15 - Histones are thought to be displaced as RNA...Ch. 15 - 23. What is an insulator? Describe two different...Ch. 15 - 24. What is DNA methylation? When we say that DNA...Ch. 15 - Lets suppose that a vertebrate organism carries a...Ch. 15 - 26. What is a CpG island? Where would you expect...Ch. 15 - Describe how the binding of iron regulatory...Ch. 15 - 1. Briefly describe the method of chromatin...Ch. 15 - Researchers can isolate a sample of cells, such as...Ch. 15 - Prob. 3EQCh. 15 - Prob. 4EQCh. 15 - Prob. 5EQCh. 15 - 6. As described in Chapter 21, an electrophoretic...Ch. 15 - Prob. 7EQCh. 15 - 1. Explain how DNA methylation could be used to...Ch. 15 - 2. Enhancers can occur almost anywhere in DNA and...
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