细胞功能测定

Traditional methods for surveying meiotic recombination in humans are limited to pedigree and linkage disequilibrium analyses. We have developed assays that allow the direct detection of crossover and gene conversion molecules in batches of sperm DNA. To date, we have characterized ...

The recombination between homologous chromosomes during the prophase of the first meiotic division plays an essential role in the formation of euploid gametes, as well as contributing to genetic diversity through the generation of new allele combinations. Two types of products are for ...

Cooperative actions of chromosomal proteins play critical roles in the dynamics, structural transition, segregation, and maintenance of meiotic chromosomes. A high-resolution genome-tiling array combined with a chromatin immunoprecipitation assay (ChIP-chip) is a powe ...

During meiotic prophase a number of important events require recombination between maternal and paternal chromosomes, which is initiated through the introduction of DNA double-strand breaks (DSBs). The majority of DSBs, which mostly occur at so-called hotspots, have been located b ...

One of the major features of meiosis is a high frequency of homologous recombination that not only confers genetic diversity to a successive generation but also ensures proper segregation of chromosomes. Meiotic recombination is initiated by DNA double-strand breaks that require many ...

The fission yeast Schizosaccharomyces pombe has many biological characteristics that make it an ideal model organism for the study of meiosis. A nearly synchronous meiosis is one of the most important. Under certain environmental and genetic conditions, large cultures of S. pombe can be in ...

Joint Molecule (JM) recombination intermediates result from DNA strand-exchange between homologous chromosomes. Physical monitoring of JM formation in budding yeast has provided a wealth of information about the timing and mechanism of meiotic recombination. These assays are ...

The SPO11 protein generates programmed DNA double-strand breaks (DSBs) that initiate meiotic recombination. Endonucleolytic cleavage 3′ to the DSB sites releases SPO11 from DNA, leaving SPO11 covalently associated with an oligonucleotide. This chapter describes detection of ...

During meiosis Spo11 catalyzes the formation of DNA double-strand breaks, becoming covalently attached to the 5′ ends on both sides of the break during this process. Spo11 is removed from the DSB by single-stranded endonucleolytic cleavage flanking the DSB, liberating a short-lived spec ...

DNA double-strand breaks (DSBs) initiate meiotic recombination in eukaryotes. We describe two strategies that use microarrays to determine the genome-wide distribution of meiotic DSBs in the yeast Saccharomyces cerevisiae. The first is a chromatin immunoprecipitation (ChIP) ...

The study of location and intensity of double-strand breaks (DSBs) in mammalian systems is more challenging than in yeast because, unlike yeast, the progression through meiosis is not synchronous and only a small fraction of all testis cells are actually at the stage where DSB formation is initi ...

Measuring meiotic gene conversion is important both because of its role in the fundamental mechanisms of meiotic recombination and because of its influence on linkage relationships and allelic diversity in the genome. Historically, gene conversion has been most thoroughly examin ...

Caenorhabditis elegans is an important experimental organism for the study of recombination during meiosis. A variety of techniques have been developed for the measurement of meiotic recombination in C. elegans, ranging from traditional genetic measures to direct cytological d ...

The fission yeast Schizosaccharomyces pombe is well-suited for studying meiotic recombination. Methods are described here for culturing S. pombe and for genetic assays of intragenic recombination (gene conversion), intergenic recombination (crossing-over), and spore via ...

Several methods have been developed to measure interactions between homologous chromosomes during meiosis in budding yeast. These include cytological analysis of fixed, spread nuclei using fluorescence in situ hybridization (FISH) (1, 2), visualization of GFP-labeled chrom ...

Interest in crossover interference in yeast has been spurred by the discovery and characterization of mutants that alter it as well as by the development and testing of models to explain it. This chapter describes methods for detecting and for measuring interference, with emphasis on those th ...

Meiotic recombination is initiated by DNA double-strand breaks (DSBs) formed by the evolutionary conserved Spo11 protein. Along the S. cerevisiae chromosomes, the DSB sites are not evenly distributed and the cleavage frequencies vary 10–100-fold from site to site. Herein are reviewed t ...

Different sporulation and pre-sporulation regimens were compared for a number of commonly used laboratory strains of S. cerevisiae to define conditions that support high-efficiency sporulation.

One of the most important principles of scientific endeavour is that the results be reproducible from lab to lab. Although research groups rarely redo the published experiments of their colleagues, research plans almost always rely on the work of someone else. The assumption is that if the same e ...

Progress in tissue engineering has led to the development of technologies allowing the reconstruction of autologous tissues from the patient’s own cells. Thus, tissue-engineered epithelial substitutes produced from cultured skin epithelial cells undergo long-term regene ...