... the process of recombination. Here, we chart the evolutionary history of Spo11 and compare the protein to its ancestors. Evolving from the A subunit of archaeal topoisomerase VI (Topo VI), a heterotetrameric type II topoisomerase, Spo11 appears to have evolved alongside meiosis and been present in the last...

...Linda Chen; John R. Weir Meiotic recombination, a cornerstone of eukaryotic diversity and individual genetic identity, is essential for the creation of physical linkages between homologous chromosomes, facilitating their faithful segregation during meiosis I. This process requires that germ cells...

... Digital Library in an all-inclusive Read & Publish agreement with Portland Press and the Biochemical Society under a transformative agreement with MPDL. coarsening crossover DNA recombination E3 ligases HEI10 meiosis Meiotic crossovers (COs) between homologous chromosomes lead...

...James D. Higgins; Kim Osman; Stuart D. Desjardins; Ian R. Henderson; Keith J. Edwards; F. Chris H. Franklin Wheat is a major cereal crop that possesses a large allopolyploid genome formed through hybridisation of tetraploid and diploid progenitors. During meiosis, crossovers (COs) are constrained...

... of the egg. Chromosome segregation is driven by a microtubule spindle, which captures and separates the paired chromosomes during meiosis I, and sister chromatids during meiosis II. Recent studies reveal that defects in the organization of the acentrosomal meiotic spindle contribute to human egg aneuploidy...

... asymmetric cell division and the segregation of the two pairs of homologous chromosomes. The newly created mature egg rearrests at metaphase of the second meiotic division prior to ovulation and only completes meiosis following a Ca 2+ signal initiated by the sperm at gamete fusion. Here, we review...

...Ee Phie Tan; Francesca E. Duncan; Chad Slawson Cell division (mitosis) and gamete production (meiosis) are fundamental requirements for normal organismal development. The mammalian cell cycle is tightly regulated by different checkpoints ensuring complete and precise chromosomal segregation...

... the ability to perform meiosis, and ultimately generating gametes, which are cells that carry recombined half sets of the parental genome and are able to fertilize. These functions have been allocated to a highly specialized cell lineage: the germline. Given its significant evolutionary conservation...

... by the Yamamoto laboratory as a suppressor of the uncontrolled meiosis driven by a pat1 mutant. Numerous studies from this laboratory and others have established the role of the Ste11 transcription factor as the master regulator of the switch between proliferation and differentiation in fission yeast...

.... Recent investigations have extended the use of S. pombe to elucidate new roles for copper metabolism in meiotic differentiation. For example, these studies have led to the discovery of Mfc1, which turned out to be the first example of a meiosis-specific copper transporter. Whereas copper-dependent...

... crossing-over inversion meiosis recombination synaptic adjustment synaptonemal complex An inversion is a chromosomal aberration resulting from 180° rotation of the region between two breaks in the same chromosome. Inversions within the same chromosome arms are termed paracentric; those...

... regulated during meiosis. We have recently deciphered a combinatorial code that can be used to qualitatively and quantitatively predict the translational behaviour of CPE-containing mRNAs. This code defines positive and negative feedback loops that generate waves of polyadenylation and deadenylation...

...Carine Barreau; Elizabeth Benson; Helen White-Cooper Post-meiotic transcription is widespread in mammalian spermatogenesis, but is generally believed to be absent from Drosophila spermatogenesis. Genes required during meiosis, in early spermatids or later in spermiogenesis are typically transcribed...

... abnormalities as well as sensitivities to a range of DNA-damaging agents, such as UV, IR, methyl methanesulfonate and the DNA synthesis inhibitor, HU (hydroxyurea) [ 15 – 18 ]. 2 7 2007 © The Authors Journal compilation © 2007 Biochemical Society 2007 genome stability Nse2 meiosis...

.... Our recent work has shown that different susceptibility patterns are associated with the origin of the meiotic error and maternal age. For MI (meiosis I) errors, the proportion of oocytes with susceptible recombination patterns is highest among young mothers and decreases significantly in the oldest...

...G.V. Börner During meiosis, numerous DSBs (double-strand breaks) are induced along the genome which are processed via several steps into crossovers. Crossovers ensure the faithful segregation of homologous chromosomes during meiosis I. Although required for faithful chromosome segregation, DSBs...

... of meiotic non-disjunction in our species. Although this association extends to many other organisms, the factors that influence the number and placement of exchanges within a cell remain poorly understood. Like other aspects of meiosis, the control of recombination is likely to be subject to variation among...

...A. Lorenz; M.C. Whitby Homologous recombination is an important mechanism for the repair of double-strand breaks in DNA. One possible outcome of such repair is the reciprocal exchange or crossing over of DNA between chromosomes. Crossovers are beneficial during meiosis because, as well...

...S. Keeney; M.J. Neale Homologous recombination is essential for accurate chromosome segregation during meiosis in most sexual organisms. Meiotic recombination is initiated by the formation of DSBs (DNA double-strand breaks) made by the Spo11 protein. We review here recent findings pertaining...

... trypanosomes in the salivary glands of the fly before they attach to the salivary gland epithelium. 1 To whom correspondence should be addressed (email [email protected] ). 28 3 2006 © 2006 The Biochemical Society 2006 genetic exchange meiosis green fluorescent protein red...

...F.C.H. Franklin; J.D. Higgins; E. Sanchez-Moran; S.J. Armstrong; K.E. Osman; N. Jackson; G.H. Jones Immunocytochemistry reveals that the Arabidopsis mismatch repair proteins AtMSH4, AtMLH3 and AtMLH1 are expressed during prophase I of meiosis. Expression of AtMSH4 precedes AtMLH3 and AtMLH1 which...

... histone evolution meiosis ootid competition Robertsonian translocation Centromeres are typically visualized as the primary constriction point of chromosomes, laying the foundation for the kinetochore complex and the recruitment of microtubules. Thus centromeres provide an absolutely...

... and chimpanzees demonstrates very high rates of evolution of the fine-scale structure of the recombination landscape. In the light of these observations, we suggest possible resolutions of the hotspot paradox. evolution hotspot human genome meiosis recombination Evolutionary models suggest that biased...

...P. Jordan Following pre-meiotic DNA replication, homologous chromosomes must be paired and become tightly linked to ensure reductional segregation during meiosis I. Therefore initiation of homologous chromosome pairing is vital for meiosis to proceed correctly. A number of factors contribute...

... Electron microscopy of meiotic chromosome spreads led to the observation of RNs as proteinaceous ellipsoids approx. 100 nm in diameter appearing early in prophase I of meiosis; the molecular events of recombination are thought to occur in these structures [ 37 , 38 ]. Two types of RN, ENs (early nodules...

...M.C. Whitby Homologous recombination (HR) is required to promote both correct chromosome segregation and genetic variation during meiosis. For this to be successful recombination intermediates must be resolved to generate reciprocal exchanges or ‘crossovers’ between the homologous chromosomes...