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Homologous chromosome pairing in wheat
Journal of Cell Science, 1999ABSTRACT Bread wheat is a hexaploid (AABBDD, 2n=6x=42) containing three related ancestral genomes, each having 7 chromosomes, giving 42 chromosomes in diploid cells. During meiosis true homologues are correctly associated in wild-type wheat, but a degree of association of related chromosomes (homoeologues) occurs in a mutant (ph1b).
E, Martínez-Pérez +5 more
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To pair or not to pair: chromosome pairing and evolution
Current Opinion in Plant Biology, 1998Chromosome pairing in wild-type wheat closely resembles the process in both yeast and Drosophila. The recent characterisation of a mutant Ph1 wheat and the observation that chromosome pairing in the absence of Ph1 more closely resembles that of mammals and maize has shed light on the evolution of chromosome pairing in the cereals.
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Pairing at the chromosomal level
Journal of Cellular Physiology, 1967The discovery of the phenomenon of nonhomologous pairing in the female of Drosophila melanogaster provided a genetic tool for analyzing chromosome behavior, which has made it possible to establish a temporal order of meiotic events that includes two types of pairing, one preceding exchange (exchange pairing) and one following exchange (distributive ...
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Joint Classification and Pairing of Human Chromosomes
IEEE/ACM Transactions on Computational Biology and Bioinformatics, 2005We reexamine the problems of computer-aided classification and pairing of human chromosomes, and propose to jointly optimize the solutions of these two related problems. The combined problem is formulated into one of optimal three-dimensional assignment with an objective function of maximum likelihood. This formulation poses two technical challenges: 1)
Pravesh Biyani +2 more
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Philosophical Transactions of the Royal Society of London. B, Biological Sciences, 1977
Abstract Commonly accepted precepts are challenged : (1) that homologous chromosome pairing is normally mediated by nuclear envelope attachment sites; (2) that crossover site establishment awaits synaptic completion; and (3) that it is the function of the synaptonemal complex to hold homologues in register so that equal crossing over ...
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Abstract Commonly accepted precepts are challenged : (1) that homologous chromosome pairing is normally mediated by nuclear envelope attachment sites; (2) that crossover site establishment awaits synaptic completion; and (3) that it is the function of the synaptonemal complex to hold homologues in register so that equal crossing over ...
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A cytophotometric study of chromosome pairing
Chromosoma, 19561. Confirming earlier studies (Schrader 1945a and b), the chromosomes of the harlequin lobe of the testis of the pentatomid Loxa flavicolis are found to be asynaptic throughout late meiotic prophase and to divide equationally at metaphase I. All other lobes show a normal meiosis. 2.
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Centromere pairing precedes meiotic chromosome pairing in plants
Science China Life Sciences, 2017Meiosis is a specialized eukaryotic cell division, in which diploid cells undergo a single round of DNA replication and two rounds of nuclear division to produce haploid gametes. In most eukaryotes, the core events of meiotic prophase I are chromosomal pairing, synapsis and recombination.
Jing, Zhang, Fangpu, Han
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THE PAIRING OF AN ALIEN CHROMOSOME WITH HOMOEOLOGOUS CHROMOSOMES OF WHEAT
Canadian Journal of Genetics and Cytology, 1972The homoeology of chromosome A of Triticum umbellulatum has been determined by studying its pairing relationships with wheat telocentrics in hybrids having the chromosome constitution of 20 wheat chromosomes + one wheat telocentric chromosome + seven Triticum speltoides chromosomes + chromosome A.
Raghbir S. Athwal, Gordon Kimber
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Mechanism of Chromosome Pairing during Meiosis
Nature, 1970Electron microscopy with whole mount preparations has revealed that the synaptonemal complex merely pulls two homologous chromosomes together. Intimate molecular pairing is another matter—probably brought about by connexions between short stretches of single stranded DNA.
D E, Comings, T A, Okada
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Chromosome Pairing: Effect of Colchicine on an Isochromosome
Science, 1970Two separable stages in the process of chromosome pairing have been demonstrated. The first results in a close spatial relationship of homologs, and the second results in synapsis and formation of chiasmata. Colchicine reduces chiasma formation in conventional bivalents but not in an isochromosome.
C J, Driscoll, N L, Darvey
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