keyword
MENU ▼
Read by QxMD icon Read
search

Homologous chromosome pairing

keyword
https://www.readbyqxmd.com/read/28100589/meiotic-consequences-of-genetic-divergence-across-the-murine-pseudoautosomal-region
#1
Beth L Dumont
The production of haploid gametes during meiosis is dependent on the homology-driven processes of pairing, synapsis, and recombination. On the mammalian heterogametic sex chromosomes, these key meiotic activities are confined to the pseudoautosomal region (PAR), a short region of near-perfect sequence homology between the X and Y chromosomes. Despite its established importance for meiosis, the PAR is rapidly evolving, raising the question of how proper X/Y segregation is buffered against the accumulation of homology-disrupting mutations...
January 18, 2017: Genetics
https://www.readbyqxmd.com/read/28092459/toward-high-throughput-and-multiplexed-imaging-of-genome-organization
#2
Eric F Joyce
Dr. Eric Joyce from the Department of Genetics at the University of Pennsylvania was awarded The President's Innovation award at the annual Society of Biomolecular Imaging and Informatics meeting held in Boston, September 2016. Chromosome interactions are a fundamental aspect of nuclear organization that can activate and silence genes or even direct chromosome rearrangements. However, the molecular mechanisms underlying how chromosomal segments find each other and form stable interactions within cells remain unknown...
January 2017: Assay and Drug Development Technologies
https://www.readbyqxmd.com/read/28077446/regulating-chromosomal-movement-by-the-cochaperone-fkb-6-ensures-timely-pairing-and-synapsis
#3
Benjamin Alleva, Nathan Balukoff, Amy Peiper, Sarit Smolikove
In meiotic prophase I, homologous chromosome pairing is promoted through chromosome movement mediated by nuclear envelope proteins, microtubules, and dynein. After proper homologue pairing has been established, the synaptonemal complex (SC) assembles along the paired homologues, stabilizing their interaction and allowing for crossing over to occur. Previous studies have shown that perturbing chromosome movement leads to pairing defects and SC polycomplex formation. We show that FKB-6 plays a role in SC assembly and is required for timely pairing and proper double-strand break repair kinetics...
January 11, 2017: Journal of Cell Biology
https://www.readbyqxmd.com/read/28074715/comparison-of-three-different-primer-sets-for-sexing-birds
#4
Emel Çakmak, Çiğdem Akın Pekşen, C Can Bilgin
Because many bird species are monomorphic or only sexually dimorphic in adult stages, it is difficult to determine their sexes, which may cause significant problems in population and conservation studies. DNA-based sexing relies on the chromodomain helicase DNA binding ( CHD) gene located on the W chromosome and its homolog on the Z chromosome, giving distinct banding patterns on agarose gel as a result of length differences in intronic regions within this gene. We used 3 specific primer sets, CHD1F/CHD1R, 2550F/2718R, and P2/P8, for sex determination of 230 samples from 77 avian species...
January 2017: Journal of Veterinary Diagnostic Investigation
https://www.readbyqxmd.com/read/28059715/control-of-meiotic-pairing-and-recombination-by-chromosomally-tethered-26s-proteasome
#5
Jasvinder S Ahuja, Rima Sandhu, Rana Mainpal, Crystal Lawson, Hanna Henley, Patricia A Hunt, Judith L Yanowitz, G Valentin Börner
During meiosis, paired homologous chromosomes (homologs) become linked via the synaptonemal complex (SC) and crossovers. Crossovers mediate homolog segregation and arise from self-inflicted double-strand breaks (DSBs). Here, we identified a role for the proteasome, the multi-subunit protease that degrades proteins in the nucleus and cytoplasm, in homolog juxtaposition and crossing over. Without proteasome function, homologs failed to pair and instead remained associated with non-homologous chromosomes. While dispensable for non-crossover formation, a functional proteasome was required for a coordinated transition that entails SC assembly between longitudinally organized chromosome axes and stable strand exchange of crossover-designated DSBs...
January 5, 2017: Science
https://www.readbyqxmd.com/read/28050734/sororin-is-enriched-at-the-central-region-of-synapsed-meiotic-chromosomes
#6
Philip W Jordan, Craig Eyster, Jingrong Chen, Roberto J Pezza, Susannah Rankin
During meiotic prophase, cohesin complexes mediate cohesion between sister chromatids and promote pairing and synapsis of homologous chromosomes. Precisely how the activity of cohesin is controlled to promote these events is not fully understood. In metazoans, cohesion establishment between sister chromatids during mitotic divisions is accompanied by recruitment of the cohesion-stabilizing protein Sororin. During somatic cell division cycles, Sororin is recruited in response to DNA replication-dependent modification of the cohesin complex by ESCO acetyltransferases...
January 3, 2017: Chromosome Research
https://www.readbyqxmd.com/read/28049850/resolution-of-single-and-double-holliday-junction-recombination-intermediates-by-gen1
#7
Rajvee Shah Punatar, Maria Jose Martin, Haley D M Wyatt, Ying Wai Chan, Stephen C West
Genetic recombination provides an important mechanism for the repair of DNA double-strand breaks. Homologous pairing and strand exchange lead to the formation of DNA intermediates, in which sister chromatids or homologous chromosomes are covalently linked by four-way Holliday junctions (HJs). Depending on the type of recombination reaction that takes place, intermediates may have single or double HJs, and their resolution is essential for proper chromosome segregation. In mitotic cells, double HJs are primarily dissolved by the BLM helicase-TopoisomeraseIIIα-RMI1-RMI2 (BTR) complex, whereas single HJs (and double HJs that have escaped the attention of BTR) are resolved by structure-selective endonucleases known as HJ resolvases...
January 17, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28045371/the-synaptonemal-complex-has-liquid-crystalline-properties-and-spatially-regulates-meiotic-recombination-factors
#8
Ofer Rog, Simone Köhler, Abby F Dernburg
The synaptonemal complex (SC) is a polymer that spans ~100nm between paired homologous chromosomes during meiosis. Its striated, periodic appearance in electron micrographs led to the idea that transverse filaments within this structure 'crosslink' the axes of homologous chromosomes, stabilizing their pairing. SC proteins can also form polycomplexes, three-dimensional lattices that recapitulate the periodic structure of SCs but do not associate with chromosomes. Here we provide evidence that SCs and polycomplexes contain mobile subunits and that their assembly is promoted by weak hydrophobic interactions, indicative of a liquid crystalline phase...
January 3, 2017: ELife
https://www.readbyqxmd.com/read/28031483/speedy-a-cdk2-binding-mediates-initial-telomere-nuclear-envelope-attachment-during-meiotic-prophase-i-independent-of-cdk2-activation
#9
Zhaowei Tu, Mustafa Bilal Bayazit, Hongbin Liu, Jingjing Zhang, Kiran Busayavalasa, Sanjiv Risal, Jingchen Shao, Ande Satyanarayana, Vincenzo Coppola, Lino Tessarollo, Meenakshi Singh, Chunwei Zheng, Chunsheng Han, Zijiang Chen, Philipp Kaldis, Jan-Åke Gustafsson, Kui Liu
Telomere attachment to the nuclear envelope (NE) is a prerequisite for chromosome movement during meiotic prophase I that is required for pairing of homologous chromosomes, synapsis, and homologous recombination. Here we show that Speedy A, a noncanonical activator of cyclin-dependent kinases (Cdks), is specifically localized to telomeres in prophase I male and female germ cells in mice, and plays an essential role in the telomere-NE attachment. Deletion of Spdya in mice disrupts telomere-NE attachment, and this impairs homologous pairing and synapsis and leads to zygotene arrest in male and female germ cells...
January 17, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28028016/multiple-and-asymmetrical-origin-of-polyploid-dog-rose-hybrids-rosa-l-sect-caninae-dc-ser-involving-unreduced-gametes
#10
V Herklotz, C M Ritz
BACKGROUND AND AIMS: Polyploidy and hybridization are important factors for generating diversity in plants. The species-rich dog roses (Rosa sect. Caninae) originated by allopolyploidy and are characterized by unbalanced meiosis producing polyploid egg cells (usually 4x) and haploid sperm cells (1x). In extant natural stands species hybridize spontaneously, but the extent of natural hybridization is unknown. The aim of the study was to document the frequency of reciprocal hybridization between the subsections Rubigineae and Caninae with special reference to the contribution of unreduced egg cells (5x) producing 6x offspring after fertilization with reduced (1x) sperm cells...
December 27, 2016: Annals of Botany
https://www.readbyqxmd.com/read/28025319/molecular-cytogenetic-characterization-of-chromosome-site-specific-repetitive-sequences-in-the-arctic-lamprey-lethenteron-camtschaticum-petromyzontidae
#11
Junko Ishijima, Yoshinobu Uno, Mitsuo Nunome, Chizuko Nishida, Shigehiro Kuraku, Yoichi Matsuda
All extant lamprey karyotypes are characterized by almost all dot-shaped microchromosomes. To understand the molecular basis of chromosome structure in lampreys, we performed chromosome C-banding and silver staining and chromosome mapping of the 18S-28S and 5S ribosomal RNA (rRNA) genes and telomeric TTAGGG repeats in the Arctic lamprey (Lethenteron camtschaticum). In addition, we cloned chromosome site-specific repetitive DNA sequences and characterized them by nucleotide sequencing, chromosome in situ hybridization, and filter hybridization...
December 26, 2016: DNA Research: An International Journal for Rapid Publication of Reports on Genes and Genomes
https://www.readbyqxmd.com/read/28018375/genome-wide-identification-localization-and-expression-analysis-of-proanthocyanidin-associated-genes-in-brassica
#12
Xianjun Liu, Ying Lu, Mingli Yan, Donghong Sun, Xuefang Hu, Shuyan Liu, Sheyuan Chen, Chunyun Guan, Zhongsong Liu
Proanthocyanidins (PA) is a type of prominent flavonoid compound deposited in seed coats which controls the pigmentation in all Brassica species. Annotation of Brassica juncea genome survey sequences showed 72 PA genes; however, a functional description of these genes, especially how their interactions regulate seed pigmentation, remains elusive. In the present study, we designed 19 primer pairs to screen a bacterial artificial chromosome (BAC) library of B. juncea. A total of 284 BAC clones were identified and sequenced...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27989672/bloom-syndrome-helicase-promotes-meiotic-crossover-patterning-and-homolog-disjunction
#13
Talia Hatkevich, Kathryn P Kohl, Susan McMahan, Michaelyn A Hartmann, Andrew M Williams, Jeff Sekelsky
In most sexually reproducing organisms, crossover formation between homologous chromosomes is necessary for proper chromosome disjunction during meiosis I. During meiotic recombination, a subset of programmed DNA double-strand breaks (DSBs) are repaired as crossovers, with the remainder becoming noncrossovers [1]. Whether a repair intermediate is designated to become a crossover is a highly regulated decision that integrates several crossover patterning processes, both along chromosome arms (interference and the centromere effect) and between chromosomes (crossover assurance) [2]...
January 9, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/27986806/repair-of-meiotic-dna-breaks-and-homolog-pairing-in-mouse-meiosis-requires-a-minichromosome-maintenance-mcm-paralog
#14
Adrian J McNairn, Vera D Rinaldi, John C Schimenti
The mammalian Mcm-domain containing 2 (Mcmdc2) gene encodes a protein of unknown function that is homologous to the mini-chromosome maintenance family of DNA replication licensing and helicase factors. Drosophila melanogaster contains two separate genes, the "Mei-MCMs," that appear to have arisen from a single ancestral Mcmdc2 gene. The Mei-MCMs are involved in promoting meiotic crossovers by blocking the anti-crossover activity of BLM helicase, a function presumably performed by MSH4 and MSH5 in metazoans...
December 16, 2016: Genetics
https://www.readbyqxmd.com/read/27986793/a-snp-based-linkage-map-of-the-arctic-charr-salvelinus-alpinus-genome-provides-insights-into-the-diploidization-process-after-whole-genome-duplication
#15
Cameron M Nugent, Anne A Easton, Joseph D Norman, Moira M Ferguson, Roy G Danzmann
Diploidization, which follows whole genome duplication events, does not occur evenly across the genome. In salmonid fishes, certain pairs of homeologous chromosomes preserve tetraploid loci in higher frequencies towards the telomeres due to residual tetrasomic inheritance. Research suggests this occurs only in homeologous pairs where one chromosome arm has undergone a fusion event. We present a linkage map for Arctic charr (Salvelinus alpinus), a salmonid species with relatively fewer chromosome fusions. Genotype by sequencing identified 19,418 SNPs and a linkage map consisting of 4508 markers was constructed from a subset of high quality SNPs and microsatellite markers that were used to anchor the new map to previous versions...
December 16, 2016: G3: Genes—Genomes—Genetics
https://www.readbyqxmd.com/read/27965412/rmi1-and-top3%C3%AE-limit-meiotic-co-formation-through-their-c-terminal-domains
#16
Mathilde Séguéla-Arnaud, Sandrine Choinard, Cécile Larchevêque, Chloé Girard, Nicole Froger, Wayne Crismani, Raphael Mercier
At meiosis, hundreds of programmed DNA double-strand breaks (DSBs) form and are repaired by homologous recombination. From this large number of DSBs, only a subset yields crossovers (COs), with a minimum of one CO per chromosome pair. All DSBs must be repaired and every recombination intermediate must be resolved to avoid subsequent entanglement and chromosome breakage. The conserved BLM-TOP3α-RMI1 (BTR) complex acts on early and late meiotic recombination intermediates to both limit CO outcome and promote chromosome integrity...
December 13, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27956489/physical-mapping-of-amplified-5-enolpyruvylshikimate-3-phosphate-synthase-gene-copies-in-glyphosate-resistant-amaranthus-tuberculatus
#17
Andrew J Dillon, Vijay K Varanasi, Tatiana Danilova, Dal-Hoe Koo, Sridevi Nakka, Dallas Peterson, Patrick Tranel, Bernd Friebe, Bikram S Gill, Mithila Jugulam
Recent and rapid evolution of resistance to glyphosate, the most widely used herbicides, in several weed species, including Amaranthus tuberculatus, poses a serious threat to sustained crop production. We report that glyphosate resistance in A. tuberculatus was due to amplification of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene, which encodes the molecular target of glyphosate. There was a positive correlation between EPSPS gene copies and its transcript expression. We analyzed the distribution of EPSPS copies in the genome of A...
December 12, 2016: Plant Physiology
https://www.readbyqxmd.com/read/27913618/meiotic-centromere-coupling-and-pairing-function-by-two-separate-mechanisms-in-saccharomyces-cerevisiae
#18
Emily L Kurdzo, David Obeso, Hoa Chuong, Dean S Dawson
In meiosis I, chromosomes become paired with their homologous partners and then are pulled towards opposite poles of the spindle. In the budding yeast, Saccharomyces cerevisiae, in early meiotic prophase, centromeres are observed to associate in pairs in a homology-independent manner, a process called centromere coupling. Later, as homologous chromosomes align, their centromeres associate in a process called centromere pairing. The synaptonemal complex protein Zip1 is necessary for both types of centromere association...
December 2, 2016: Genetics
https://www.readbyqxmd.com/read/27909815/homoeologous-recombination-in-the-presence-of-ph1-gene-in-wheat
#19
Dal-Hoe Koo, Wenxuan Liu, Bernd Friebe, Bikram S Gill
A crossover (CO) and its cytological signature, the chiasma, are major features of eukaryotic meiosis. The formation of at least one CO/chiasma between homologous chromosome pairs is essential for accurate chromosome segregation at the first meiotic division and genetic recombination. Polyploid organisms with multiple sets of homoeologous chromosomes have evolved additional mechanisms for the regulation of CO/chiasma. In hexaploid wheat (2n = 6× = 42), this is accomplished by pairing homoeologous (Ph) genes, with Ph1 having the strongest effect on suppressing homoeologous recombination and homoeologous COs...
December 1, 2016: Chromosoma
https://www.readbyqxmd.com/read/27900493/mining-the-cicer-arietinum-genome-for-the-mildew-locus-o-mlo-gene-family-and-comparative-evolutionary-analysis-of-the-mlo-genes-from-medicago-truncatula-and-some-other-plant-species
#20
Reena Deshmukh, V K Singh, Brahma Deo Singh
The mildew locus O (Mlo) gene family is ubiquitous in land plants. Some members of this gene family are involved in negative regulation of powdery mildew resistance, while others are involved in several other biological functions. Mlo proteins have characteristic seven transmembrane domains and a calmodulin-binding domain at their C-termini, and are associated with plasma membrane. The Mlo gene family has been studied in several economically important cereals, but little information is available on this gene family in the important legumes, Medicago truncatula Gaertn...
November 30, 2016: Journal of Plant Research
keyword
keyword
103023
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"