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Schematic diagram of the eukaryotic plex that is
required for the transcription of DNA to messenger RNA. The PART
TATA-box binding protein is shown in orange. V
EXPRESSION AND
TRANSMISSION
OF IC
INFORMATION
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Chapter Nucleic Acid
29 Structures
1 Double Helical Structures RNA and one-third protein, have functional as well as
A. B-DNA structural roles.
B. Other Nucleic Acid Helices
3. During protein synthesis, amino acids are delivered
2 Forces Stabilizing Nucleic Acid Structures
to the ribosome by molecules of transfer RNA (tRNA).
A. Sugar–Phosphate Chain Conformations
B. Base Pairing 4. Certain RNAs are associated with specific proteins
C. Base Stacking and Hydrophobic Interactions to form ribonucleoproteins that participate in the post-
D. Ionic Interactions transcriptional processing of other RNAs.
3 Supercoiled DNA 5. In many viruses, RNA, not DNA, is the carrier of
A. Superhelix Topology hereditary information.
B. Measurements of Supercoiling
C. Topoisomerases The structure and properties of DNA are introduced in
Section 5-5. In this chapter we extend this discussion with
emphasis on DNA; the structures of RNAs are detailed
in Sections 31-4A and 32-2B. Methods of purifying, se-
There are two classes of nucleic acids, deoxyribonucleic quencing, and chemically synthesizing nucleic acids are dis-
acid (DNA) and ribonucleic acid (RNA). DNA is the cussed in Sections 6-6, 7-2, and 7-5, and binant DNA
hereditary molecule in all cellular life-forms, as well as in techniques are discussed in Section 5-5. Bioinformatics, as
many viruses. It has but two functions: it concerns nucleic acids, is outlined in Section 7-4, and the
1. To direct its own replication during cell division. Nucleic Acid Database is described