Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
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Chapter 18, Problem 11PDQ
In 1998, future Nobel laureates Andrew Fire and Craig Mello, and colleagues, published an article in Nature entitled, “Potent and Specific Genetic Interference by Double-Stranded RNA in Caenorhabditis elegans.” Explain how RNAi is both “potent and specific.”
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Searching the yeast Saccharomyces cerevisiae genome, researchers found approximately 4,000 DNA sites with a sequence which could potentially bind the yeast transcription factor GAL4. GAL4 activates the transcription of galactose genes. Yet there are only 10 GAL4-binding sites which control the genes necessary for galactose metabolism. The GAL4 binding sequence is CGGAT#AGAAGC*GCCG, where # is T, C or G, and * is C or T.
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Chapter 18 Solutions
Concepts of Genetics (12th Edition)
Ch. 18 - Some mutations in the tra gene of Drosophila cause...Ch. 18 - Some scientists use the analogy that the...Ch. 18 - Consider the example that actin mRNA localization...Ch. 18 - What is alternative splicing, where does it occur,...Ch. 18 - What role might the expanded tri- and...Ch. 18 - DM1 is characterized by a phenomenon known as...Ch. 18 - HOW DO WE KNOW? In this chapter, we focused on how...Ch. 18 - CONCEPT QUESTION Review the Chapter Concepts list...Ch. 18 - List three types of alternative splicing patterns...Ch. 18 - Consider the CT/CGRP example of alternative...
Ch. 18 - Explain how the use of alternative promoters and...Ch. 18 - Explain how a tissue-specific RNA-binding protein...Ch. 18 - The regulation of mRNA decay relies heavily upon...Ch. 18 - Nonsense-mediated decay is an mRNA surveillance...Ch. 18 - AU-rich elements (AREs) are cis-elements in mRNAs...Ch. 18 - What are processing bodies (P bodies), and what...Ch. 18 - In 1998, future Nobel laureates Andrew Fire and...Ch. 18 - Present an overview of RNA interference (RNAi)....Ch. 18 - RNAi may be directed by small interfering RNAs...Ch. 18 - Prob. 14PDQCh. 18 - In principle, RNAi may be used to fight viral...Ch. 18 - Prob. 16PDQCh. 18 - Prob. 17PDQCh. 18 - Prob. 18PDQCh. 18 - Prob. 19PDQCh. 18 - How is it possible that a given mRNA in a cell is...Ch. 18 - Prob. 21PDQCh. 18 - Prob. 22PDQCh. 18 - Prob. 23PDQCh. 18 - Prob. 24ESPCh. 18 - Prob. 25ESPCh. 18 - Mutations in the low-density lipoprotein receptor...Ch. 18 - RNA helicases are a class of proteins that bind...Ch. 18 - While miRNA response elements (MREs) may be...Ch. 18 - RNAi is currently being tested as a therapeutic...Ch. 18 - The localization and translational control of...Ch. 18 - Explain how the expression of a single gene can be...
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- 4) The fact that splicing is a strategy to optimize the use of the genome in eukaryotes is evidenced in C. elegans, which with 20,000 genes can synthesize more than 20,000 proteins. True or false 7) The mutation in the myostatin protein that results in mice with hypertrophied muscles results from a premature stop codon that results in a truncated (shorter than necessary) protein that loses its function of stopping cell division of muscle cells. What post-transcriptional quality control mechanisms fail here? (two apply) a) polyadenylation b) NMD c) splicing d) capping e) methylation 10) The nuclear transplant experiment results in: a) KO or knockout b) transgenic organisms c) RNAi (interference) d) animal cloningarrow_forwardCertain mutations called amber in bacteria and viruses result in premature termination of polypeptide chains during translation. Many amber mutationshave been detected at different points along the gene thatcodes for a head protein in phage T4. How might this system be further investigated to demonstrate and support the concept ofcolinearity?arrow_forward(c) By binding one L-tryptophan molecule/monomer, the trp repressor binds to DNA to suppress syn- thesis of L-tryptophan in E. coli. Below is the amino acid sequence of the helix – (reverse) turn – helix region of the trp repressor that binds to DNA compared to the sequence of the corresponding DNA binding motif of the Prl protein, a different type of repressor protein. A diagram of the trp repressor dimer is also shown. reverse turn trp helix 4 70 Trp -Gly-Glu-Met-Ser-Gln-Arg-Glu-Leu-Lys-Asn-Glu-Leu-Gly-Ala-Gly- Ile- Prl -Ser-Glu-Glu-Ala-Lys-Glu-Glu-Leu-Ala-Lys-Lys-Cys-Gly-Ile-Thr- Val- Pri heilix trp helix 5 80 90 Trp Ala-Thr-Ile-Thr-Arg-Gly-Ser sgn-Ser-Leu-Lys-Ala-Ala- Prl Ser-Gln-Val-Ser-Asn-Trp-Phe-Gly-Asn-Lys-Arg-Ile-Arg- Prl helixarrow_forward
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