William S. Klug
Michael R. Cummings
Charlotte A. Spencer
Concepts of Genetics
Eighth Edition
Chapter 14
Translation and Proteins
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Translation of mRNA
Depends on Ribosomes and
Transfer RNAs
Ribosomal Structure
Figure 14-1
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tRNA Structure
Figure 14-2
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Figure 14-3
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Figure 14-4
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Charging tRNA
Figure 14-5
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Translation of mRNA Can
Be Divided into Three Steps
Table 14-1
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Initiation
Figure 14-6
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Elongation
Termination
Figure 14-8
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Polyribosomes
Figure 14-9
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Figure 14-9a
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Figure 14-9b
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Crystallographic Analysis
Has Revealed Many Details
about the Functional
Prokaryotic Ribosome
Translation Is More
Complex in Eukaryotes
The Initial Insight That
Proteins Are Important in
Heredity Was Provided by
the Study of Inborn Errors of
Metabolism
Figure 14-10
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Phenylketonuria
Studies of Neurospora Led
to the One-Gene:OneEnzyme Hypothesis
Analysis of Neurospora Mutants by
Beadle and Tatum
Figure 14-11
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Figure 14-11a
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Figure 14-11b
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Figure 14-11c
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Genes and Enzymes: Analysis of
Biochemical Pathways
Figure 14-12
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Studies of Human
Hemoglobin Established
That One Gene Encodes
One Polypeptide
Sickle-Cell Anemia
Figure 14-13
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Figure 14-13a
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Figure 14-13b
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Figure 14-14
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Human Hemoglobins
Table 14-2
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The Nucleotide Sequence
of a Gene and the Amino
Acid Sequence of the
Corresponding Protein
Exhibit Colinearity
Figure 14-15
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Protein Structure Is the Basis of
Biological Diversity
Protein Structure Is the
Basis of Biological Diversity
Posttranslational Modification
• N –terminus is ususally modified
• Amino acids may be modified, i.e.—phosphorylation
• Carboydrates can be added (glycoproteins)
• Polypeptides may be trimmed
• Signal sequences may be removed
• Polypeptides may complex with metals
• Some polypeptides must be folded by chaperones
Protein Function Is Directly
Related to the Structure of
the Molecule
Proteins Are Made Up of
One or More Functional
Domains
Exon Shuffling and the Origin of
Protein Domains
Figure 14-22
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