Chapter 13

DNA Structure and Function

The DNA Helix
Overview Deoxyribonucleic acid, or DNA, is the genetic material responsible for passing traits from generation to generation in all organisms and…
DNA Packaging
13.2: DNA Packaging
Overview Eukaryotes have large genomes compared to prokaryotes. In order to fit their genomes into a cell, eukaryotes must pack their DNA tightly…
Organization of Genes
13.3: Organization of Genes
Overview The genomes of eukaryotes can be structured in several functional categories. A strand of DNA is comprised of genes and intergenic regions.…
Karyotyping
13.4: Karyotyping
Overview Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is…
Replication in Prokaryotes
13.5: Replication in Prokaryotes
Overview DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins…
Replication in Eukaryotes
13.6: Replication in Eukaryotes
Overview In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high…
Proofreading
13.7: Proofreading
Overview Synthesis of new DNA molecules starts when DNA polymerase links nucleotides together in a sequence that is complementary to the template…
Mismatch Repair
13.8: Mismatch Repair
Overview Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires…
Nucleotide Excision Repair
13.9: Nucleotide Excision Repair
Overview Exposure to mutagens can damage DNA and result in bulky lesions that distort the double-helix structure or impede proper transcription.…
Mutations
13.10: Mutations
Overview Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental…
Transcription
13.11: Transcription
Overview Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a…
Translation
13.12: Translation
Overview Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription,…
Bioengineering: Folding and Characterization of a Bio-responsive Robot from DNA Origami
13.14: Bioengineering: Folding and Characterization of a Bio-responsive Robot from DNA Origami
Structural DNA nanotechnology uses nucleic acid as a self-assembling elementary unit for the construction of arbitrary shapes. This protocol…
Genetics: Targeted in situ Mutagenesis of Histone Genes in Budding Yeast
13.15: Genetics: Targeted in situ Mutagenesis of Histone Genes in Budding Yeast
Histones play roles in the organization and function of eukaryotic chromosomes, and in budding yeast, each is encoded by two genes. This article…
Biology: The ChIP-exo Method and Identifying Protein-DNA Interactions with Near Base-Pair Precision
13.16: Biology: The ChIP-exo Method and Identifying Protein-DNA Interactions with Near Base-Pair Precision
Chromatin immunoprecipitation is a tool used to isolate specific protein-DNA interactions, however, some protocols provide low mapping precision and…
Immunology: A Simple Chelex Protocol for DNA Extraction from Anopheles spp.
13.17: Immunology: A Simple Chelex Protocol for DNA Extraction from Anopheles spp.
This video describes a rapid and affordable way to extract quality malaria parasite and vector DNA from mosquito specimens. Capitalizing on the…
Genetics: Identifying Transcription Factor Olig2 Genomic Binding Sites in Acutely Purified PDGFRα+ Cells by Low-cell Chromatin Immunoprecipitation Sequencing Analysis
13.18: Genetics: Identifying Transcription Factor Olig2 Genomic Binding Sites in Acutely Purified PDGFRα+ Cells by Low-cell Chromatin Immunoprecipitation Sequencing Analysis
A major goal in genetics is to understand how gene transcription is regulated. The binding of transcription factor proteins to DNA is a major…
Examination of Telomere Structure
13.20: Examination of Telomere Structure
Chromosome analysis is routinely used by researchers and clinicians to observe chromosomal abnormalities and diagnose disease. In this video, Howe et…
Investigation of the Mechanism of Action of a DNA Repair Protein
13.21: Investigation of the Mechanism of Action of a DNA Repair Protein
The Msh2-Msh6 protein complex is responsible for initiating repair of replication errors in eukaryotic DNA. In this video, Biro et al. use a…
Atomic Force Microscopy Investigations of DNA Lesion Recognition in Nucleotide Excision Repair
13.22: Atomic Force Microscopy Investigations of DNA Lesion Recognition in Nucleotide Excision Repair
Atomic force microscopy (AFM) is a method that uses a mechanical probe to investigate structures on the nanometer scale. At this resolution,…