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Ubeda Francisco F School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK - - 2015
Most animals and many plants make use of specialized chromosomes (sex chromosomes) to determine an individual's sex. Best known are the XY and ZW sex-determination systems. Despite having evolved numerous times, sex chromosomes present something of an evolutionary puzzle. At their origin, alleles that dictate development as one sex or ...
Fontoura Nathalia - - 2014
BackgroundComplexes of cryptic species are common in several taxa and this is also the case in the Anopheles genus, a group including all known human malaria vectors. The Anopheles albitarsis complex comprises at least nine cryptic species, some of which are implicated as vectors of human malaria. Several different types ...
van Hemmen Judy J Netherlands Institute for Neuroscience, Amsterdam, The Netherlands Department of Medical Psychology, Neuroscience Campus - - 2014
Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a ...
Ghadge Amita G - - 2014
Background Coccinia grandis is a dioecious species of Cucurbitaceae having heteromorphic sex chromosomes. The chromosome constitution of male and female plants is 22¿+¿XY and 22¿+¿XX respectively. Y chromosome of male sex is conspicuously large and plays a decisive role in determining maleness. Sex modification has been studied in hypogynous Silene ...
Pokorná Martina Johnson MJ Department of Ecology, Faculty of Science, Charles University in Prague, Viničná 7, Praha 2, Czech Republic; Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburská 89, Liběchov, Czech - - 2014
Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode ...
Manwani Bharti B Department of Neurology and Neuroscience, University of Connecticut Health Center, Farmington, Connecticut, - - 2014
Epidemiologic studies have shown sex differences in ischemic stroke. The four core genotype (FCG) mouse model, in which the testes determining gene, Sry, has been moved from Y chromosome to an autosome, was used to dissociate the effects of sex hormones from sex chromosome in ischemic stroke outcome. Middle cerebral ...
Hoehn Kenneth B KB University of Oxford; Duke University; Oriel College; - - 2014
The scuttle fly, Megaselia scalaris, is often cited as model in which to study early sex chromosome evolution because of its homomorphic sex chromosomes, low but measurable molecular differentiation between sex chromosomes, and occasional transposition of the male-determining element to different chromosomes in laboratory cultures. Counterintuitively, natural isolates consistently show ...
Peng Di D Center for Reproductive Medicine, The First Bethune Hospital of Jilin University, Changchun, Jilin, 130021, - - 2014
Patients with a karyotype of 45,X (monosomy X) normally display a female phenotype. However, in some rare cases, monosomy X is associated with maleness. Here we describe a case of a male with a 45,X karyotype and primary infertility, which prompted molecular investigation of the sex-determination gene SRY. Karyotyping was ...
Gennotte Vincent V Aquaculture Research and Education Center (CEFRA), AFFISH-RC, University of Liè, ge, Tihange, - - 2014
This study aimed to develop sex reversal procedures targeting the embryonic period as tools to study the early steps of sex differentiation in Nile tilapia with XX, XY, and YY sexual genotypes. XX eggs were exposed to masculinizing treatments with androgens (17α-methyltestosterone, 11-ketotestosterone) or aromatase inhibitor (Fadrozole), whereas XY and ...
Tachon G G Département de Génétique Médicale, CHRU Montpellier, Faculté de Médecine Université Montpellier 1, Montpellier, France Laboratoire de Génétique Chromosomique, Hôpital Arnaud de Villeneuve, CHRU Montpellier, Montpellier, - - 2014
We report a case of discordant phenotypic sex in monozygotic twins mosaic 47,XXY/46,XX: monozygotic heterokaryotypic twins. The twins presented with cognitive and comprehension delay, behavioural and language disorders, all symptoms frequently reported in Klinefelter syndrome. Molecular zygosity analysis with several markers confirmed that the twins are in effect monozygotic (MZ). ...
Ross Benjamin D BD Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA; Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N. A2-025, Seattle, WA 98109, - - 2014
Female meiosis presents unique opportunities for competition between chromosomes for evolutionary dominance. A new study reveals that centromere strength dictates meiotic success, driving karyotype evolution and reproductive isolation in mice.
Anaya Gabriel G Laboratory of Animal Genomics, MERAGEM (AGR-158) Research Group, Department of Genetics, University of Córdoba, - - 2014
Horses are characterized as having a greater rate of chromosomal abnormalities than other species, which are mainly related to the sex chromosome pair and produce a series of different anomalies known as disorders in sexual development (DSD). In the present study, three Pura Raza Española (PRE) and one Menorquín (MEN) ...
Mank Judith E JE Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United - - 2014
Intralocus sexual conflict and intragenomic conflict both affect sex chromosome evolution and can in extreme cases even cause the complete turnover of sex chromosomes. Additionally, established sex chromosomes often become the focus of heightened conflict. This creates a tangled relationship between sex chromosomes and conflict with respect to cause and ...
Kate Ushang V UV Senior Scientific Officer & Quality Manager, Department of Cytogenetics, PreventiNe Life Care Pvt Ltd. , Mumbai, India - - 2014
Background and objectives: The chromosomal abnormalities are one of the important causes of male infertility. In view of the genetic risks for the next generation, the importance of careful evaluation of karyotype is essential. The objective of this study was to determine the frequency of chromosomal abnormalities in infertile men ...
Schmid Michael M Department of Human Genetics, Biocenter, University of Würzburg, Würzburg, - - 2014
The chromosomes of the turnip-tailed gecko Thecadactylus rapicauda from the Falcón State in northern Venezuela were examined by means of conventional staining, a variety of banding techniques and in situ hybridization with an 18S + 28S rDNA probe. In female specimens, C-banding analyses detected a cryptic W sex chromosome-associated interstitial ...
Dufresnes Christophe C Department of Ecology and Evolution, Biophore Building, University of Lausanne, 1015, - - 2014
Occasional XY recombination is a proposed explanation for the sex-chromosome homomorphy in European tree frogs. Numerous laboratory crosses, however, failed to detect any event of male recombination, and a detailed survey of NW-European Hyla arborea populations identified male-specific alleles at sex-linked loci, pointing to the absence of XY recombination in ...
Valenzuela Nicole N Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, - - 2014
Sex determination is triggered by factors ranging from genotypic (GSD) to environmental (ESD), or both GSD + EE (GSD susceptible to environmental effects), and its evolution remains enigmatic. The presence/absence of sex chromosomes purportedly separates species at the ESD end of the continuum from the rest (GSD and GSD + ...
Ahmed Sophia S Integrative Biology of Marine Models, CNRS UMR 8227, Sorbonne Universités, UPMC Université Paris 6, Station Biologique de Roscoff, CS 90074, 29688 Roscoff, France; Medical Biology Centre, Queens University Belfast, Belfast BT9 7BL, Northern Ireland, - - 2014
A common feature of most genetic sex-determination systems studied so far is that sex is determined by nonrecombining genomic regions, which can be of various sizes depending on the species. These regions have evolved independently and repeatedly across diverse groups. A number of such sex-determining regions (SDRs) have been studied ...
Bajic Vladan V University of Belgrade, Institute for Nuclear Sciences "Vinca", Department of Radiobiology and Molecular Genetics, Belgrade, - - 2014
X-chromosome instability has been a long established feature in Alzheimer's disease (AD). Premature centromere division and aneuploidy of the X-chromosome has been found in peripheral blood lymphocytes and neuronal tissue in female AD patients. Interestingly, only one chromosome of the X pair has been affected. These results raised a question, ...
Herrera Paul P Biosciences, University of Exeter Cornwall Campus, Penryn, TR10 9FE, - - 2014
Female multiple mating, known as polyandry, is ubiquitous and occurs in a wide variety of taxa. Polyandry varies greatly from species in which females mate with one or two males in their lifetime to species in which females may mate with several different males on the same day. As multiple ...
Lima Thiago G TG Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, - - 2014
The two 'rules of speciation', Haldane's rule and the large X-effect, describe the genetic basis of postzygotic isolation, and have led to the realization that sex chromosomes play an important role in this process. However, a range of sex determination mechanisms exists in nature, not always involving sex chromosomes. Based ...
Kumbıçak Zübeyde Z Department of Molecular Biology and Genetics, Faculty of Science and Art, Nevşehir Hacı Bektaş Veli University, 50300, Nevşehir, - - 2014
In this study, the karyotypes of six spider species from Turkey belonging to the families Gnaphosidae, Salticidae, Thomisidae, and Zodariidae were analyzed. Male chromosomal features including diploid chromosome numbers and sex chromosome systems were determined as 2n=22, X1X20 in Drassyllus sur Tuneva & Esyunin, 2003, Nomisia exornata (C. L. Koch, ...
Asgharian Hosseinali H Program in Molecular and Computational Biology, Department of Biological Sciences, University of Southern California Los Angeles, CA, - - 2014
Wolbachia causes the feminization of chromosomally male embryos in several species of crustaceans and insects, including the leafhopper Zyginidia pullula. In contrast to the relatively well-established ecological aspects of male feminization (e.g., sex ratio distortion and its consequences), the underlying molecular mechanisms remain understudied and unclear. We embarked on an ...
Ali Rola H RH Department of Pathology, Faculty of Medicine, Health Sciences Center, Kuwait University, P.O. Box 24923, Safat 13110, Kuwait. - - 2014
Gender-related differences in colorectal cancer (CRC) are not fully understood. Recent studies have shown that CRC arising in females are significantly associated with CpG island methylator phenotype (CIMP-high). Using array comparative genomic hybridization, we analyzed a cohort of 116 CRCs (57 males, 59 females) for chromosomal copy number aberrations (CNA) ...
Romero María Luciana ML Laboratorio de Genética de la Estructura Poblacional, Departamento de Ecología, Genética y Evolución, Instituto IEGEBA (CONICET-UBA), Facultad de Ciencias, Exactas y Naturales, Universidad de Buenos Aires, Argentina Present address: Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina - - 2014
The water-hyacinth grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) is native to South America and inhabits lowlands from southern Mexico to central Argentina and Uruguay. This grasshopper feeds and lays eggs on species from the genera Eichhornia and Pontederia. Particularly, Eichhornia crassipes is considered "the world's worst water weed," and the ...
Jouyan Najmeh N Human Genetic Research Group, Iranian Academic Center for Education, Culture and Research, Fars Province Branch, Shiraz, Iran. ; Institute of Biochemistry and Biophysics, Tehran University, Tehran, - - 2012
Chromosome abnormality (CA) including Sex chromosomes abnormality (SCAs) is one of the most important causes of disordered sexual development and infertility. SCAs formed by numerical or structural alteration in X and Y chromosomes, are the most frequently CA encountered at both prenatal diagnosis and at birth. This study describes cytogenetic ...
Skinner B M - - 2012
It is generally believed that the organization of avian genomes remains highly conserved in evolution as chromosome number is constant and comparative chromosome painting demonstrated there to be very few interchromosomal rearrangements. The recent sequencing of the zebra finch (Taeniopygia guttata) genome allowed an assessment of the number of intrachromosomal ...
Suh Alexander - - 2011
The vast majority of extant birds possess highly differentiated Z and W sex chromosomes. Nucleotide sequence data from gametologs (homologs on opposite sex chromosomes) suggest that this divergence occurred throughout early bird evolution via stepwise cessation of recombination between identical sex chromosomal regions. Here we investigated avian sex chromosome differentiation ...
Velichko Artem K - - 2011
Heterochromatin protein 1 (HP1) was discovered as a protein essential for maintaining the silent transcriptional status of genes located within or close to centromeric regions of Drosophila chromosomes. Mammals express three variants of HP1; of these, HP1α is a direct homolog of Drosophila HP1. The prevailing view states that HP1 ...
Carneiro Miguel M CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, 4485-661, Vairão, Portugal. - - 2010
Studies of gene flow between closely related taxa can provide insight into the genetic basis of speciation. To evaluate the importance of the X chromosome in reproductive isolation between subspecies of the European rabbit and to study the genomic scale over which islands of differentiation extend, we resequenced a total ...
Dimitriadis Emilios K - - 2010
Mitosis ensures equal genome segregation in the eukaryotic lineage. This process is facilitated by microtubule attachment to each chromosome via its centromere. In centromeres, canonical histone H3 is replaced in nucleosomes by a centromere-specific histone H3 variant (CENH3), providing the unique epigenetic signature required for microtubule binding. Due to recent ...
Yamagishi Yuya - - 2010
For proper partitioning of chromosomes in mitosis, the chromosomal passenger complex (CPC) including Aurora B and survivin must be localized at the center of paired kinetochores, at the site called the inner centromere. It is largely unknown what defines the inner centromere and how the CPC is targeted to this ...
Tanno Yuji - - 2010
Shugoshin (Sgo) is a conserved centromeric protein. Mammalian Sgo1 collaborates with protein phosphatase 2A (PP2A) to protect mitotic cohesin from the prophase dissociation pathway. Although another shugoshin-like protein, Sgo2, is required for the centromeric protection of cohesion in germ cells, its precise molecular function remains largely elusive. We demonstrate that ...
Obado Samson O - - 2011
Topoisomerase-II accumulates at centromeres during prometaphase, where it resolves the DNA catenations that represent the last link between sister chromatids. Previously, using approaches including etoposide-mediated topoisomerase-II cleavage, we mapped centromeric domains in trypanosomes, early branching eukaryotes in which chromosome segregation is poorly understood. Here, we show that in bloodstream form ...
Qi Lili - - 2010
The evolution of five chromosomes of Brachypodium distachyon from a 12-chromosome ancestor of all grasses by dysploidy raises an interesting question about the fate of redundant centromeres. Three independent but complementary approaches were pursued to study centromeric region homologies among the chromosomes of Brachypodium, wheat, and rice. The genes present ...
Tsukahara Tatsuya - - 2010
Successful partition of replicated genomes at cell division requires chromosome attachment to opposite poles of mitotic spindle (bi-orientation). Any defects in this regulation bring about chromosomal instability, which may accelerate tumour progression in humans. To achieve chromosome bi-orientation at prometaphase, the chromosomal passenger complex (CPC), composed of catalytic kinase Aurora ...
Wang Fangwei F Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Smith Building, 1 Jimmy Fund Way, Boston, MA 02115, - - 2010
Aurora B is a component of the chromosomal passenger complex (CPC) required for correct spindle-kinetochore attachments during chromosome segregation and for cytokinesis. The chromatin factors that recruit the CPC to centromeres are unknown, however. Here we show that phosphorylation of histone H3 threonine 3 (H3T3ph) by Haspin is necessary for ...
Ryu Hyunju H Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045, - - 2010
SUMO conjugation of cellular proteins is essential for proper progression of mitosis. PIASy, a SUMO E3 ligase, is required for mitotic SUMOylation of chromosomal proteins, yet the regulatory mechanism behind the PIASy-dependent SUMOylation during mitosis has not been determined. Using a series of truncated PIASy proteins, we have found that ...
Stimpson Kaitlin M - - 2010
Genome rearrangement often produces chromosomes with two centromeres (dicentrics) that are inherently unstable because of bridge formation and breakage during cell division. However, mammalian dicentrics, and particularly those in humans, can be quite stable, usually because one centromere is functionally silenced. Molecular mechanisms of centromere inactivation are poorly understood since ...
Stimpson Kaitlin M - - 2010
The centromere is a complex chromosomal locus where the kinetochore is formed and microtubules attach during cell division. Centromere identity involves both genomic and sequence-independent (epigenetic) mechanisms. Current models for how centromeres are formed and, conversely, turned off have emerged from studies of unusual or engineered chromosomes, such as neocentromeres, ...
Dubin Manu - - 2010
The centromeric histone H3 variant (CenH3) serves to target the kinetochore to the centromeres and thus ensures correct chromosome segregation during mitosis and meiosis. The Dictyostelium H3-like variant H3v1 was identified as the CenH3 ortholog. Dictyostelium CenH3 has an extended N-terminal domain with no similarity to any other known proteins ...
Bassett Emily A EA Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, - - 2010
The nearly ubiquitous presence of repetitive centromere DNA sequences across eukaryotic species is in paradoxical contrast to their apparent functional dispensability. Centromeric chromatin is spatially delineated into the kinetochore-forming array of centromere protein A (CENP-A)-containing nucleosomes and the inner centromeric heterochromatin that lacks CENP-A but recruits the aurora B kinase ...
Mehta Gunjan D - - 2010
The centromere is a genetic locus, required for faithful chromosome segregation, where spindle fibers attach to the chromosome through kinetochore. Loss of centromere or formation of multiple centromeres on a single chromosome leads to chromosome missegregation or chromosome breakage, respectively, which are detrimental for fitness and survival of a cell. ...
Ewers Elisabeth - - 2010
Twenty-five dicentric small supernumerary marker chromosomes (sSMC) derived from #13/21, #14, #15, #18, and #22 were studied by immunohistochemistry for their centromeric activity. Centromere protein (CENP)-B was applied as marker for all centromeres and CENP-C to label the active ones. Three different 'predominant' activation patterns could be observed, i.e., centric ...
Manning Amity L - - 2010
Chromosome instability (CIN) is a common feature of tumor cells. By monitoring chromosome segregation, we show that depletion of the retinoblastoma protein (pRB) causes rates of missegregation comparable with those seen in CIN tumor cells. The retinoblastoma tumor suppressor is frequently inactivated in human cancers and is best known for ...
Lukaszewski A J - - 2010
Centromeres are responsible for the proper behavior of chromosomes in cell divisions. In meiosis the process is more complicated than in mitosis, as each chromosome in a bivalent has 2 sister centromeres and their behavior has to be strictly coordinated. Here, the behavior of sister centromeres in univalents in wheat ...
Guerra M - - 2010
The centromere appears as a single constriction at mitotic metaphase in most eukaryotic chromosomes. Holokinetic chromosomes are the exception to this rule because they do not show any centromeric constrictions. Holokinetic chromosomes are usually forgotten in most reviews about centromeres, despite their presence in a number of animal and plant ...
Shang Wei-Hao - - 2010
The centromere is essential for faithful chromosome segregation by providing the site for kinetochore assembly. Although the role of the centromere is conserved throughout evolution, the DNA sequences associated with centromere regions are highly divergent among species and it remains to be determined how centromere DNA directs kinetochore formation. Despite ...
Zhang Wenli - - 2010
A chromosome with two functional centromeres is cytologically unstable and can only be stabilized when one of the two centromeres becomes inactivated via poorly understood mechanisms. Here, we report a transmissible chromosome with multiple centromeres in wheat. This chromosome encompassed one large and two small domains containing the centromeric histone ...
Ellermeier Chad - - 2010
During meiosis, the formation of viable haploid gametes from diploid precursors requires that each homologous chromosome pair be properly segregated to produce an exact haploid set of chromosomes. Genetic recombination, which provides a physical connection between homologous chromosomes, is essential in most species for proper homologue segregation. Nevertheless, recombination is ...
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