scholarly journals Novel Genes Required for Meiotic Chromosome Segregation Are Identified by a High-Throughput Knockout Screen in Fission Yeast

2005 ◽  
Vol 15 (18) ◽  
pp. 1663-1669 ◽  
Author(s):  
Juraj Gregan ◽  
Peter K. Rabitsch ◽  
Benjamin Sakem ◽  
Ortansa Csutak ◽  
Vitaly Latypov ◽  
...  
Keyword(s):  
Fission Yeast ◽  
Chromosome Segregation ◽  
High Throughput ◽  
Meiotic Chromosome ◽  
Novel Genes

scholarly journals Shake It Off: The Elimination of Erroneous Kinetochore-Microtubule Attachments and Chromosome Oscillation

2021 ◽  
Vol 22 (6) ◽  
pp. 3174
Author(s):  
Ayumu Yamamoto
Keyword(s):  
Cell Proliferation ◽  
Sexual Reproduction ◽  
Fission Yeast ◽  
Chromosome Segregation ◽  
Meiotic Chromosome ◽  
Spindle Poles ◽  
Selective Elimination ◽  
Random Nature ◽  
Attachment Process ◽  
Segregation Of Chromosomes

Cell proliferation and sexual reproduction require the faithful segregation of chromosomes. Chromosome segregation is driven by the interaction of chromosomes with the spindle, and the attachment of chromosomes to the proper spindle poles is essential. Initial attachments are frequently erroneous due to the random nature of the attachment process; however, erroneous attachments are selectively eliminated. Proper attachment generates greater tension at the kinetochore than erroneous attachments, and it is thought that attachment selection is dependent on this tension. However, studies of meiotic chromosome segregation suggest that attachment elimination cannot be solely attributed to tension, and the precise mechanism of selective elimination of erroneous attachments remains unclear. During attachment elimination, chromosomes oscillate between the spindle poles. A recent study on meiotic chromosome segregation in fission yeast has suggested that attachment elimination is coupled to chromosome oscillation. In this review, the possible contribution of chromosome oscillation in the elimination of erroneous attachment is discussed in light of the recent finding.

scholarly journals Immediate visualization of recombination events and chromosome segregation defects in fission yeast meiosis

2018 ◽  
Author(s):  
Dmitriy Li ◽  
Marianne Rocl ◽  
Raif Yuecel ◽  
Alexander Lorenz
Keyword(s):  
Fission Yeast ◽  
Chromosome Segregation ◽  
High Throughput ◽  
Meiotic Recombination ◽  
Recombination Frequency ◽  
Genetic Interval ◽  
Chromosome Iii ◽  
Yeast Meiosis ◽  
Chromosome I ◽  
High Throughput Screens

AbstractSchizosaccharomyces pombe, also known as fission yeast, is an established model for studying chromosome biological processes. Over the years research employing fission yeast has made important contributions to our knowledge about chromosome segregation during meiosis, as well as meiotic recombination and its regulation. Quantification of meiotic recombination frequency is not a straightforward undertaking, either requiring viable progeny for a genetic plating assay, or relying on laborious Southern blot analysis of recombination intermediates. Neither of these methods lends itself to high-throughput screens to identify novel meiotic factors. Here, we establish visual assays novel to Sz. pombe for characterizing chromosome segregation and meiotic recombination phenotypes. Genes expressing red, yellow, and/or cyan fluorophores from spore-autonomous promoters have been integrated into the fission yeast genomes, either close to the centromere of chromosome I to monitor chromosome segregation, or on the arm of chromosome III to form a genetic interval at which recombination frequency can be determined. The visual recombination assay allows straightforward and immediate assessment of the genetic outcome of a single meiosis by epi-fluorescence microscopy without requiring tetrad dissection. We also demonstrate that the recombination frequency analysis can be automatized by utilizing imaging flow cytometry to enable high-throughput screens. These assays have several advantages over traditional methods for analysing meiotic phenotypes.

scholarly journals Double or nothing: a Drosophila mutation affecting meiotic chromosome segregation in both females and males.

Genetics ◽  
1994 ◽  
Vol 136 (3) ◽  
pp. 953-964 ◽  
Author(s):  
D P Moore ◽  
W Y Miyazaki ◽  
J E Tomkiel ◽  
T L Orr-Weaver
Keyword(s):  
Cell Death ◽  
Chromosome Segregation ◽  
Sister Chromatid ◽  
Meiotic Chromosome ◽  
Sister Chromatid Cohesion ◽  
Aberrant Chromosome ◽  
Chromatid Cohesion ◽  
Meiotic Nondisjunction ◽  
Lethal Allele ◽  
Meiosis I

Abstract We describe a Drosophila mutation, Double or nothing (Dub), that causes meiotic nondisjunction in a conditional, dominant manner. Previously isolated mutations in Drosophila specifically affect meiosis either in females or males, with the exception of the mei-S332 and ord genes which are required for proper sister-chromatid cohesion. Dub is unusual in that it causes aberrant chromosome segregation almost exclusively in meiosis I in both sexes. In Dub mutant females both nonexchange and exchange chromosomes undergo nondisjunction, but the effect of Dub on nonexchange chromosomes is more pronounced. Dub reduces recombination levels slightly. Multiple nondisjoined chromosomes frequently cosegregate to the same pole. Dub results in nondisjunction of all chromosomes in meiosis I of males, although the levels are lower than in females. When homozygous, Dub is a conditional lethal allele and exhibits phenotypes consistent with cell death.

Abstract 12905: Gene Expression and Expression Quantifying Trait Loci Analysis of Left Atrium of Patients With Post-operative Atrial Fibrillation

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Martin I Sigurdsson ◽  
Mahyar Heydarpour ◽  
Louis Saddic ◽  
Tzuu-Wang Chang ◽  
Stanton K Shernan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Atrial Fibrillation ◽  
Left Atrium ◽  
High Throughput ◽  
Specific Gene ◽  
Eqtl Analysis ◽  
Gene Variants ◽  
Nucleotide Polymorphisms ◽  
Novel Genes ◽  
Trait Loci

Introduction: The majority of information on the genetic background of atrial fibrillation (AF) results from genomic DNA variant analysis without consideration of tissue expression. Hypothesis: Analysis of tissue-specific gene expression in left atrium (LA) can further understanding of the molecular mechanism of identified AF risk variants, and identify novel genes and gene variants associated with AF. Methods: We isolated mRNA from samples of the LA free wall taken during mitral valve surgery in 62 Caucasian individuals. Gene expression in the LA was compared between patients who did and did not have post-operative AF (poAF) using high-throughput RNA expression. Using genotypes of 1.4 million single nucleotide polymorphisms (SNP) we performed cis expression quantifying trait loci (eQTL) analysis, correlating gene expression of each gene with the genotypes of adjacent (<1Mbp) SNPs. Results: We identified 23 differentially expressed genes in the LA of patients with poAF, including three potassium channel genes (KCNA7, KCNH8 and KCNK17). The largest expression difference was in LOC645323, a long non-coding RNA. The expression of PITX2, ZFHX3 and KCNN3, previously shown to be associated with AF, did not differ between patients with and without poAF. We identified 12,476 cis eQTL relationships in the LA, several of those included genetic regions and genes previously associated with AF. We confirmed an eQTL relationship between rs3744029 genotype and the expression of MYOZ1. Furthermore we describe a novel eQTL relationship between rs6795970 genotype and the expression of the SCN10A gene. Conclusions: We have analysed the human LA expression via high-throughput RNA sequencing, and identified novel genes and gene variants likely involved in the molecular pathophysiology of AF.

scholarly journals DeepTetrad: high-throughput analysis of meiotic tetrads by deep learning in plants

2019 ◽  
Author(s):  
Eun-Cheon Lim ◽  
Jaeil Kim ◽  
Jihye Park ◽  
Eun-Jung Kim ◽  
Juhyun Kim ◽  
...  
Keyword(s):  
Deep Learning ◽  
Chromosome Segregation ◽  
High Throughput ◽  
Fluorescent Protein ◽  
Genetic Dissection ◽  
Crossover Frequency ◽  
Tetrad Analysis ◽  
High Throughput Analysis ◽  
Crossover Interference ◽  
Pollen Tetrad

AbstractMeiotic crossovers facilitate chromosome segregation and create new combinations of alleles in gametes. Crossover frequency varies along chromosomes and crossover interference limits the coincidence of closely spaced crossovers. Crossovers can be measured by observing the inheritance of linked transgenes expressing different colors of fluorescent protein in Arabidopsis pollen tetrads. Here we establish DeepTetrad, a deep learning-based image recognition package for pollen tetrad analysis that enables high-throughput measurements of crossover frequency and interference in individual plants. DeepTetrad will accelerate genetic dissection of mechanisms that control meiotic recombination.

scholarly journals Differential requirement for Bub1 and Bub3 in regulation of meiotic versus mitotic chromosome segregation

2020 ◽  
Vol 219 (4) ◽  
Author(s):  
Gisela Cairo ◽  
Anne M. MacKenzie ◽  
Soni Lacefield
Keyword(s):  
Chromosome Segregation ◽  
Protein Phosphatase ◽  
Mitotic Chromosome ◽  
Budding Yeast ◽  
Meiotic Chromosome ◽  
Protein Phosphatase 1 ◽  
Aurora B ◽  
Chromosome Missegregation ◽  
Anaphase Onset ◽  
Spindle Microtubules

Accurate chromosome segregation depends on the proper attachment of kinetochores to spindle microtubules before anaphase onset. The Ipl1/Aurora B kinase corrects improper attachments by phosphorylating kinetochore components and so releasing aberrant kinetochore–microtubule interactions. The localization of Ipl1 to kinetochores in budding yeast depends upon multiple pathways, including the Bub1–Bub3 pathway. We show here that in meiosis, Bub3 is crucial for correction of attachment errors. Depletion of Bub3 results in reduced levels of kinetochore-localized Ipl1 and concomitant massive chromosome missegregation caused by incorrect chromosome–spindle attachments. Depletion of Bub3 also results in shorter metaphase I and metaphase II due to premature localization of protein phosphatase 1 (PP1) to kinetochores, which antagonizes Ipl1-mediated phosphorylation. We propose a new role for the Bub1–Bub3 pathway in maintaining the balance between kinetochore localization of Ipl1 and PP1, a balance that is essential for accurate meiotic chromosome segregation and timely anaphase onset.

scholarly journals A microtubule polymerase cooperates with the kinesin-6 motor and a microtubule cross-linker to promote bipolar spindle assembly in the absence of kinesin-5 and kinesin-14 in fission yeast

2017 ◽  
Vol 28 (25) ◽  
pp. 3647-3659 ◽  
Author(s):  
Masashi Yukawa ◽  
Tomoki Kawakami ◽  
Masaki Okazaki ◽  
Kazunori Kume ◽  
Ngang Heok Tang ◽  
...  
Keyword(s):  
Fission Yeast ◽  
Chromosome Segregation ◽  
Spindle Pole Body ◽  
Spindle Assembly ◽  
Spindle Pole ◽  
Temperature Sensitive ◽  
Bipolar Spindle ◽  
Pole Body ◽  
Cross Linker ◽  
Spindle Elongation

Accurate chromosome segregation relies on the bipolar mitotic spindle. In many eukaryotes, spindle formation is driven by the plus-end–directed motor kinesin-5 that generates outward force to establish spindle bipolarity. Its inhibition leads to the emergence of monopolar spindles with mitotic arrest. Intriguingly, simultaneous inactivation of the minus-end–directed motor kinesin-14 restores spindle bipolarity in many systems. Here we show that in fission yeast, three independent pathways contribute to spindle bipolarity in the absence of kinesin-5/Cut7 and kinesin-14/Pkl1. One is kinesin-6/Klp9 that engages with spindle elongation once short bipolar spindles assemble. Klp9 also ensures the medial positioning of anaphase spindles to prevent unequal chromosome segregation. Another is the Alp7/TACC-Alp14/TOG microtubule polymerase complex. Temperature-sensitive alp7cut7pkl1 mutants are arrested with either monopolar or very short spindles. Forced targeting of Alp14 to the spindle pole body is sufficient to render alp7cut7pkl1 triply deleted cells viable and promote spindle assembly, indicating that Alp14-mediated microtubule polymerization from the nuclear face of the spindle pole body could generate outward force in place of Cut7 during early mitosis. The third pathway involves the Ase1/PRC1 microtubule cross-linker that stabilizes antiparallel microtubules. Our study, therefore, unveils multifaceted interplay among kinesin-dependent and -independent pathways leading to mitotic bipolar spindle assembly.

Sign in / Sign up

Export Citation Format

Share Document