遗传学实验技术

The immunoglobulin (Ig) genes of B cells are diversified at high rate by point mutations whereas the non-Ig genes of B cells accumulate no or significantly fewer mutations. Ig hypermutations are critical for the affinity maturation of antibodies for most of jawed vertebrates and also contri ...

Homologous recombination (HR) is a mode of double-strand break (DSB) repair required for cell viability in vertebrate cells. Targeted integration of homologous DNA fragment by HR is usually a very rare event in vertebrate cells; however, in chicken B lymphoma cell line DT40, the ratio of target ...

DNA interstrand cross-links (ICLs) covalently link both strands of the DNA duplex, impeding cellular processes like DNA replication. Homologous recombination (HR) is considered to be a major pathway for the repair of ICLs in mammalian cells as mutants for HR components are highly sensiti ...

Homologous recombination during meiosis is critical for the formation of gametes. Recombination is initiated by programmed DNA double-strand breaks which preferentially occur at hotspots dispersed throughout the genome. These double-strand breaks are repaired from the hom ...

Homologous recombination processes, which occur during the prophase of the first meiotic division, while generating new allelic combinations, are mechanistically important for the regular segregation of homologous chromosomes. They generate either crossovers, which are ...

Recent studies have shown that the meiosis-specific kinase, Mek1, plays a key role in promoting recombination between homologous chromosomes during meiosis in budding yeast by suppressing recombination between sister chromatids, as well as playing a role in the meiotic recombinat ...

Crossovers (COs) play an essential role in promoting successful chromosome segregation during meiosis. Crossing over generates chiasmata, which are physical bridges between homologs that provide the appropriate tension to properly align chromosomes on the meiosis I spindle. H ...

During meiosis, programmed double strand breaks give rise to crossover and non-crossover recombination products. Meiotic recombination products are formed via several branched intermediates, including single end invasions and double Holliday junctions. Two-dimensio ...

Multiple types of DNA damage, including bulky adducts, DNA single-strand breaks, and DNA double-strand breaks (DSBs), have deleterious effects on the genomes of eukaryotes. DSBs form normally during a variety of biological processes, such as V–D–J recombination and yeast mating type swi ...

Topoisomerases can release topological stress and resolve DNA catenanes by a DNA strand breakage and re-ligation mechanism. During the lifetime of the DNA break, the topoisomerase remains covalently linked to the DNA and removes itself when the break is re-ligated. While the lifetime of a co ...

The controlled fragmentation of chromosomes by DNA double-strand breaks (DSBs) initiates meiotic recombination, which is essential for meiotic chromosome segregation in most eukaryotes. This chapter describes a straightforward microarray-based approach to measure the ...

High levels of homologous recombination are induced during meiosis. This meiotic recombination is initiated by programmed formation of DNA double-strand breaks (DSBs) by a conserved meiosis-specific protein, Spo11. Meiotic DSBs are not formed at random along chromosomes but are fo ...

Resection of DNA double-strand break (DSB) ends, which results in 3′ single-stranded tails, is an early event of DSB repair and can be a critical determinant in choice of repair pathways and eventual genome stability. Current techniques for examining resection are restricted to model in vivo sy ...

Spontaneous mitotic recombination occurs in response to DNA damage incurred during DNA replication or from lesions that do not block replication but leave recombinogenic substrates such as single-stranded DNA gaps. Other types of damages result in general genome instability such as ...

The discovery of RNA-templated DNA repair has revealed a novel case where genetic information can flow directly from RNA to genomic DNA without passing through a reverse transcript intermediate. As initially demonstrated in the yeast Saccharomyces cerevisiae via transformation by ...

Delitto perfetto is a site-specific in vivo mutagenesis system that has been developed to generate changes at will in the genome of the yeast Saccharomyces cerevisiae. Using this technique, it is possible to rapidly and efficiently engineer yeast strains without requiring several inte ...

Many systems have been developed for the study of mitotic homologous recombination (HR) in the yeast Saccharomyces cerevisiae at both genetic and molecular levels. Such systems are of great use for the analysis of different features of HR as well as of the effect of mutations, transcription, etc., ...

The huge advances that have been made in human (and other species) genome projects have been lead by, and have themselves fueled, tremendous innovations in the field of sequencing. These innovations have lead to a specialization, with very expensive equipment, often in core sequencing cente ...

Subtractive hybridization methods provide a means to isolate genes that are specifically expressed in a cell type or tissue (1–3), genes that are differentially regulated during activation or differentiation of cells (4–7), or genes that are involved in pathological conditions such as c ...

Efficient genome-engineering tools have been developed for use in whole-genome essentiality studies. In this chapter, we describe a powerful genomic deletion tool, the Tn5-targeted Cre/loxP excision system, for determining genetic essentiality and minimizing bacterial gen ...