Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Chapter 6, Problem 40P
Cre is a recombinase enzyme encoded by a gene in bacteriophage P1. The Cre enzyme promotes site-specific recombination between two copies of a 34 bp long DNA sequence called loxP that is derived from the same bacteriophage.
Researchers use the Cre/loxP site-specific recombination system in order to make mice homozygous for a deletion of any particular gene and only in a specific tissue. You will see in Chapter 18 that scientists first make mice where a pair of loxP sites are configured in a particular way with respect to the gene to be deleted.
| a. | Draw a diagram that shows the configuration of the loxP sites that would enable deletion of a gene by site-specific recombination. |
| b. | What else would the researchers need to introduce into the mouse genome in order to generate mice where only one tissue is homozygous for the gene deletion? |
| c. | Why do you think that scientists would want to generate mice like this? |
| d. | Unlike the DNA rearrangements at attP and attB sites catalyzed by ΦC31 integrase (described in Problem 39), the DNA rearrangements caused by Cre recombinase are reversible. Why? |
| e. | Why does the reversibility of Cre/loxP-mediated recombination not interfere with the use of the Cre/loxP system to generate mouse tissues with deletions? |
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Chapter 6 Solutions
Genetics: From Genes to Genomes
Ch. 6 - Griffith, in his 1928 experiments, demonstrated...Ch. 6 - Griffith, in his 1928 experiments, demonstrated...Ch. 6 - During bacterial transformation, DNA that enters a...Ch. 6 - Nitrogen and carbon are more abundant in proteins...Ch. 6 - If 30 of the bases in human DNA are A, a what...Ch. 6 - Which of the following statements are true about...Ch. 6 - Imagine you have three test tubes containing...Ch. 6 - What information about the structure of DNA was...Ch. 6 - A portion of one DNA strand of the human gene...Ch. 6 - When a double-stranded DNA molecule is exposed to...
Ch. 6 - A particular virus with DNA as its genetic...Ch. 6 - The underlying structure of DNA is very simple,...Ch. 6 - Prob. 13PCh. 6 - Bacterial transformation and bacteriophage...Ch. 6 - The CAP protein is shown bound to DNA in Fig....Ch. 6 - In Meselson and Stahls density shift experiments...Ch. 6 - When Meselson and Stahl grew E. coli in 15N medium...Ch. 6 - If you expose human tissue culture cells for...Ch. 6 - Draw a replication bubble with both replication...Ch. 6 - a. Do any strands of nucleic acid exist in nature...Ch. 6 - As Fig. 6.21 shows, DNA polymerase cleaves the...Ch. 6 - The bases of one of the strands of DNA in a region...Ch. 6 - Replicating structures in DNA can be observed in...Ch. 6 - Indicate the role of each of the following in DNA...Ch. 6 - Draw a diagram of replication that is occurring at...Ch. 6 - Figure 6.18 depicts Watson and Cricks initial...Ch. 6 - Researchers have discovered that during...Ch. 6 - A DNA synthesizer is a machine that uses automated...Ch. 6 - Bacterial cells were coinfected with two types of...Ch. 6 - A yeast strain with a mutant spo11- allele has...Ch. 6 - Imagine that you have done a cross between two...Ch. 6 - The Neurospora octad shown came from a cross...Ch. 6 - From a cross between e f g and e f g strains of...Ch. 6 - In Step 6 of Fig. 6.27, the resolvase enzyme...Ch. 6 - Figure 6.31shows four potential outcomes of...Ch. 6 - Each of the substrates for site-specific...Ch. 6 - Prob. 37PCh. 6 - Suppose that you could inject a wild-type mouse...Ch. 6 - C31 is a type of bacteriophage that infects...Ch. 6 - Cre is a recombinase enzyme encoded by a gene in...Ch. 6 - Like Cre/loxP recombination, site-specific...
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