遗传学实验技术

Regulation of many biological processes in eukaryotes involves distant communication between the regulatory DNA sequences (e.g., enhancers) and their targets over the DNA regions organized in chromatin. However previously developed methods for analysis of communication in c ...

This unit details the use of hydroxyl radicals to characterize protein–DNA interactions. This method may be used to assess the exact location of contacts between a protein and its cognate DNA and details of the complex structure. We describe several methods to prepare DNA templates for footpr ...

The uranyl-(VI) cation (UO2 2+) forms strong complexes with accessible phosphates of nucleic acid (DNA and RNA) backbones. Upon excitation with long wavelength ultraviolet light (λ = 300–420 nm), uranyl ions bound to backbone phosphates oxidize proximal sugars and induce nucleic acid back ...

Structural studies of DNA–protein complexes reveal networks of contacts between proteins and the phosphates, sugars and bases of DNA. A range of biochemical methods, termed chemical footprinting, aim to determine the functional groups on DNA which are protected in solution by bound pro ...

Sequence-specific protein/DNA contacts direct most transcription factors to binding sites within the promoters of genes they regulate. Several chemical probes, such as dimethyl sulfate, have been used to obtain information on these sites of interaction. Protection and interfer ...

Transgenesis in Drosophila melanogaster relies upon direct microinjection of embryos and subsequent crossing of surviving adults. The necessity of crossing single flies to screen for transgenic events limits the range of useful transgenesis techniques to those that have a very hi ...

Two efficient strategies have been developed and are widely used for the genetic transformation of the nematode Caenorhabditis elegans, DNA microinjection, and DNA-coated microparticle bombardment. Both methodologies facilitate the delivery of exogenous DNA into the devel ...

In the absence of germ-line-competent ES cells in the rat, pronuclear microinjection remains an essential tool to generate transgenic rat models. However, DNA microinjection procedures first developed for mouse do not provide scientists with satisfying results when applied to rat. H ...

The possibility of generating transgenic animals is of obvious advantage for the analysis of gene function in development and disease. One of the established vertebrate model systems in developmental biology is the amphibian Xenopus laevis. Different techniques have been success ...

The zebrafish (Danio rerio) is a useful model for genetic studies of vertebrate development. Its embryos are transparent and develop rapidly outside the mother, making it feasible to visualize and manipulate specific cell types in the living animal. Zebrafish is well suited for transgenic ...

Gene trapping is a powerful tool to ablate gene function and to analyze in vivo promoter activity of the trapped gene in parallel. The gene trap strategy is not as commonly used as the conventional gene-targeting strategy, although it offers appealing options. Nowadays, a wide collection of embr ...

There is a continuing need for more efficient methods to examine mutations in humans and other species resulting from exposures to environmental toxins and radiation. Environmental genomic studies, which often utilize nonmodel system species and as a result, there is a particular need f ...

The study of DNA damage at the chromosome level is an essential part of genetic toxicology because chromosomal mutation is an important event in carcinogenesis. Micronucleus assays have emerged as one of the preferred methods for assessing chromosome damage because they enable both chr ...

Numerous chemicals as well as ionizing radiations of different qualities can induce damage to chromosome integrity and/or chromosome distribution at mitosis and meiosis. Fluorescence in situ hybridization with many kinds of probes complementary to different DNA sequences has b ...

The Barcode of Life initiative represents an ambitious effort to develop an identification system for eukaryotic life based on the analysis of sequence diversity in short, standardized gene regions. Work is furthest advanced for members of the animal kingdom. In this case, a target gene regi ...

Metagenomics addresses the collective genetic structure and functional composition of a microbial environmental sample without the bias or necessity for culturing the microorganisms from the community in question. Metagenomic studies are now beginning to take advantage of t ...

Genotypes are easily measured using a variety of experimental methods. However, experimental methods for measuring haplotypes, i.e., molecular haplotyping, are limited. Instead, haplotypes often are statistically inferred from genotype data with varying degrees of confide ...

The past decades have seen the staggering development of molecular microbial ecology as a discipline that uses the detection of so-called biomarkers to monitor microbial communities in environment samples. A variety of molecules can be used as biomarkers, including cell-wall compon ...

In the field of biotechnology, fusing recombinant proteins to highly soluble partners is a common practice for overcoming aggregation in Escherichia coli. E. coli maltose-binding protein (MBP) has been recognized as one of the most effective solubilizing agents, having frequently be ...

Protein–protein interaction is one of the most pivotal roles of proteins in living organisms. Association/dissociation of proteins reflects responses to intrinsic or extrinsic perturbations of signaling pathways, involved in gene expression, cell division, cell different ...