scholarly journals The X-Chromosome Has a Different Pattern of Gene Expression in Women Compared With Men With Ischemic Stroke

Stroke ◽  
2012 ◽  
Vol 43 (2) ◽  
pp. 326-334 ◽  
Author(s):  
Boryana Stamova ◽  
Yingfang Tian ◽  
Glen Jickling ◽  
Cheryl Bushnell ◽  
Xinhua Zhan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ischemic Stroke ◽  
X Chromosome

scholarly journals X chromosome-dependent disruption of placental regulatory networks in hybrid dwarf hamsters

Genetics ◽  
2021 ◽  
Author(s):  
Thomas D Brekke ◽  
Emily C Moore ◽  
Shane C Campbell-Staton ◽  
Colin M Callahan ◽  
Zachary A Cheviron ◽  
...  
Keyword(s):  
Gene Expression ◽  
X Chromosome ◽  
Regulatory Networks ◽  
Mammalian Species ◽  
Strongly Correlated ◽  
Placental Development ◽  
Substitution Lines ◽  
Genome Wide ◽  
Highly Sensitive ◽  
First And Second Generation

AbstractEmbryonic development in mammals is highly sensitive to changes in gene expression within the placenta. The placenta is also highly enriched for genes showing parent-of-origin or imprinted expression, which is predicted to evolve rapidly in response to parental conflict. However, little is known about the evolution of placental gene expression, or if divergence of placental gene expression plays an important role in mammalian speciation. We used crosses between two species of dwarf hamsters (Phodopus sungorus and Phodopus campbelli) to examine the genetic and regulatory underpinnings of severe placental overgrowth in their hybrids. Using quantitative genetic mapping and mitochondrial substitution lines, we show that overgrowth of hybrid placentas was primarily caused by genetic differences on the maternally inherited P. sungorus X chromosome. Mitochondrial interactions did not contribute to abnormal hybrid placental development, and there was only weak correspondence between placental disruption and embryonic growth. Genome-wide analyses of placental transcriptomes from the parental species and first- and second-generation hybrids revealed a central group of co-expressed X-linked and autosomal genes that were highly enriched for maternally biased expression. Expression of this gene network was strongly correlated with placental size and showed widespread misexpression dependent on epistatic interactions with X-linked hybrid incompatibilities. Collectively, our results indicate that the X chromosome is likely to play a prominent role in the evolution of placental gene expression and the accumulation of hybrid developmental barriers between mammalian species.

Study of Dosage Compensation in Drosophila

Genetics ◽  
2003 ◽  
Vol 165 (3) ◽  
pp. 1167-1181
Author(s):  
Pei-Wen Chiang ◽  
David M Kurnit
Keyword(s):  
Gene Expression ◽  
X Chromosome ◽  
Dosage Compensation ◽  
Qpcr Assay ◽  
Male And Female ◽  
Multiple Genes ◽  
Chromosomal Changes ◽  
Regulatory Effects

Abstract Using a sensitive RT-QPCR assay, we analyzed the regulatory effects of sex and different dosage compensation mutations in Drosophila. To validate the assay, we showed that regulation for several genes indeed varied with the number of functional copies of that gene. We then confirmed that dosage compensation occurred for most genes we examined in male and female flies. Finally, we examined the effects on regulation of several genes in the MSL pathway, presumed to be involved in sex-dependent determination of regulation. Rather than seeing global alterations of either X chromosomal or autosomal genes, regulation of genes on either the X chromosome or the autosomes could be elevated, depressed, or unaltered between sexes in unpredictable ways for the various MSL mutations. Relative dosage for a given gene between the sexes could vary at different developmental times. Autosomal genes often showed deranged regulatory levels, indicating they were in pathways perturbed by X chromosomal changes. As exemplified by the BR-C locus and its dependent Sgs genes, multiple genes in a given pathway could exhibit coordinate regulatory modulation. The variegated pattern shown for expression of both X chromosomal and autosomal loci underscores the complexity of gene expression so that the phenotype of MSL mutations does not reflect only simple perturbations of genes on the X chromosome.

Autonomous gene expression on the human inactive X chromosome

1980 ◽  
Vol 6 (3) ◽  
pp. 309-323 ◽  
Author(s):  
Brenda Kahan ◽  
Robert DeMars
Keyword(s):  
Gene Expression ◽  
X Chromosome ◽  
Inactive X Chromosome

scholarly journals X chromosome regulation of autosomal gene expression in bovine blastocysts

Chromosoma ◽  
2014 ◽  
Vol 123 (5) ◽  
pp. 481-489 ◽  
Author(s):  
Yuichiro Itoh ◽  
Arthur P. Arnold
Keyword(s):  
Gene Expression ◽  
X Chromosome ◽  
Autosomal Gene

scholarly journals Sex and death: from cell fate specification to dynamic control of X-chromosome structure and gene expression

2018 ◽  
Vol 29 (22) ◽  
pp. 2616-2621 ◽  
Author(s):  
Barbara J. Meyer
Keyword(s):  
Gene Expression ◽  
Cell Fate ◽  
X Chromosome ◽  
Chromosome Structure ◽  
Dynamic Control ◽  
Three Dimensional ◽  
X Chromosomes ◽  
Meiotic Chromosomes ◽  
The Difference ◽  
Developmental Decision

Determining sex is a binary developmental decision that most metazoans must make. Like many organisms, Caenorhabditis elegans specifies sex (XO male or XX hermaphrodite) by tallying X-chromosome number. We dissected this precise counting mechanism to determine how tiny differences in concentrations of signals are translated into dramatically different developmental fates. Determining sex by counting chromosomes solved one problem but created another—an imbalance in X gene products. We found that nematodes compensate for the difference in X-chromosome dose between sexes by reducing transcription from both hermaphrodite X chromosomes. In a surprising feat of evolution, X-chromosome regulation is functionally related to a structural problem of all mitotic and meiotic chromosomes: achieving ordered compaction of chromosomes before segregation. We showed the dosage compensation complex is a condensin complex that imposes a specific three-­dimensional architecture onto hermaphrodite X chromosomes. It also triggers enrichment of histone modification H4K20me1. We discovered the machinery and mechanism underlying H4K20me1 enrichment and demonstrated its pivotal role in regulating higher-order X-chromosome structure and gene expression.

scholarly journals Random X Inactivation and Extensive Mosaicism in Human Placenta Revealed by Analysis of Allele-Specific Gene Expression along the X Chromosome

PLoS ONE ◽  
2010 ◽  
Vol 5 (6) ◽  
pp. e10947 ◽  
Author(s):  
Joana Carvalho Moreira de Mello ◽  
Érica Sara Souza de Araújo ◽  
Raquel Stabellini ◽  
Ana Maria Fraga ◽  
Jorge Estefano Santana de Souza ◽  
...  
Keyword(s):  
Gene Expression ◽  
X Chromosome ◽  
Human Placenta ◽  
X Inactivation ◽  
Specific Gene ◽  
Specific Gene Expression ◽  
Allele Specific

scholarly journals Elevated Lipocalin-2 Can Indicate the Vascular Inflammation in Patients with Ischemic Stroke

2019 ◽  
Author(s):  
Rajnics P ◽  
◽  
Kellner A ◽  
Nagy F ◽  
Alföldi V ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ischemic Stroke ◽  
Gene Expression Level ◽  
Expression Level ◽  
Neutrophil Granulocytes ◽  
Lipocalin 2 ◽  
Relative Gene Expression ◽  
Thrombotic Risk ◽  
Relative Gene ◽  
Relative Gene Expression Level

Purpose: Elevated level of Lipocalin-2 (LCN2), a new acute phase adipokine, was described after ischemic stroke. A number of researchers feel as though that LCN2 originated from the infiltrating neutrophils and other cells in brain after stroke. Others measured elevated LCN2 expression in arteriosclerotic plaque. Therefore we have investigated LCN2 relative gene expression level of blood neutrophil granulocytes in patients with ischemic stroke to assess if elevated LCN2 is the cause or consequence of ischemic stroke. Methods: Laboratory and anamnestic data were collected, which could have a role in development of thrombo-embolic events in patients with ischemic stroke. RNA based method was used to evaluate the relative gene expression level of LCN2. We calculated Odds Ratio (OR) and Confidence Interval (CI) for the association between LCN2 and ischemic stroke. Results: 34 samples were available for evaluation. The LCN 2 relative gene expression level was decreased in 12 cases. In this group, 91% of patients have Atrial Fibrillation (AF) at the time of hospitalisation. The mean LCN2 relative gene expression value was 64.25% (ranges: 34%-115%) in patients with AF. It was significantly lower than in patients with normal sinus rhythm (409.2%; ranges: 127%-1127%; p=0.0003). The elevated LCN2 relative gene expression level significantly (p=0.012) increases the risk of stroke (OR: 12.6) independently from other factors. Conclusions: High LCN2 expression level seems to have strong positive predictive value on ischemic stroke, and may be useful in thrombotic risk stratification of plaque vulnerability in these patients.

scholarly journals BRCa1 participates in XIST RNa localization on inactive x chromosome

2019 ◽  
Vol 18 (2) ◽  
pp. 21-26
Author(s):  
E. A. Shestakova ◽  
T. A. Bogush
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Confocal Microscopy ◽  
X Chromosome ◽  
Fluorescent Microscopy ◽  
S Phase ◽  
Immunofluorescent Staining ◽  
Heterochromatin Protein ◽  
Inactive X Chromosome ◽  
Xist Rna

Introduction . Inactive X chromosome (Xi) is associated with noncoding XIST RNA, series of proteins and contains multiple epigenetic modifications that altogether determine a silence of the most of X-linked genes. Recently the data were obtained that tumor suppressor BRCA1 is also associated with Xi. The purpose of this study was to reveal the colocalization of BRCA1 and XIST RNA and precise spatial organization on Xi with the high resolution of confocal microscopy.Materials and methods . The object of the study is IMR90hTERT diploid immortalized fibroblast cell line. For BRCA1 and XIST RNA colocalization analysis on Xi the method of fluorescent hybridization in situ associated with immunofluorescent cell staining (immunoFISH) and confocal microscopy were used. For BRCA1 and heterochromatin protein-1 colocalization study the method of double immunofluorescent staining and common fluorescent microscopy were applied. Results . The study using confocal fluorescent microscopy with higher resolution has demonstrated at first the colocalization of BRCA1 with XIST RNA region of Xi revealed with XIST RNA probes and with replicating Xi and autosomes revealed with BrdU in late S-phase of cell cycle. Altogether, the data obtained suggest the involvement of BRCA1 in the inhibition of gene expression on Xi due to the regulation of XIST RNA association with Xi. Moreover, according to the results of confocal microscopy, BRCA1 also colocalizes with replicating Xi and autosomes revealed with BrdU in late S-phase of cell cycle. This indicates a possible involvement of this protein in the replication of pericentromeric repeats in cellular chromosomes. Colocalization of BRCA1 with heterochromatin protein-1α presented in pericentromeric regions of all chromosomes supports this suggestion.Conclusions . Altogether, the data obtained in this study suggest the involvement of BRCA1 in the inhibition of gene expression on Xi due to the association with noncoding inhibiting XIST RNA and in replication of heterochromatin regions. 

scholarly journals Hyperexpression of TLR2 and TLR4 in patients with ischemic stroke in acute period of the disease

2020 ◽  
Vol 22 (4) ◽  
pp. 665-674
Author(s):  
L. V. Gankovskaya ◽  
L. V. Stakhovskaya ◽  
V. V. Grechenko ◽  
E. A. Koltsova ◽  
O. S. Uvarova ◽  
...  
Keyword(s):  
Gene Expression ◽  
Innate Immunity ◽  
Ischemic Stroke ◽  
Peripheral Blood ◽  
Surface Expression ◽  
Control Group ◽  
Peripheral Blood Leukocytes ◽  
Blood Leukocytes ◽  
Healthy Donors ◽  
Tlr4 Gene

Pathogenesis of ischemic stroke  is actively  involved  in the  system  of innate immunity. Under conditions of cerebral  ischemia, a number of biologically  active  substances are  released  that  interact with innate immunity receptors, in particular TLR2  and  TLR4, which  exacerbate inflammation in brain  tissue. Identification of predictor markers  at the level of the innate immunity system may foresee the clinical course of ischemic stroke and ensure timely treatment. Our objective was to study expression of TLR2 and TLR4 receptors in peripheral blood leukocytes  in patients with ischemic stroke in the dynamics of the disease. 27 people  were included in the study. The main  group consisted of patients with ischemic stroke of varying severity (n = 19). Patients of the main  group were divided into two subgroups:  with an NIHSS index value of < 10 (n = 10) and > 10 (n = 9). The control group included healthy  donors  with no history  of acute  and chronic inflammatory diseases (n = 8). Peripheral blood  leukocytes  were used as the  test material. To determine expression  of the TLR2  and TLR4  genes, RT-PCR in real time was used. Surface  expression  of TLRs was determined by flow cytometry. A study of the TLR2 and TLR4 gene expression showed that on the 1st, 3rd  and 7th  day post-stroke, the TLR4 gene expression  in patients was significantly  increased, when compared to the control group (p < 0.01), whereas TLR2 gene expression on the 3rd  day of the disease was not statistically different from the control group. A study of surface expression  of receptors showed that the average TLR2 fluorescence intensity on the patients’ peripheral blood monocytes was significantly  increased on the 1st  and 3rd  day of disease when compared to the control group.  The  surface  expression  of TLR4  on monocytes has a statistically significant  increase  only on day 7. Assessment  of surface expression  of TLRs in subgroups  with different  severity values by NIHSS showed that  patients with a NIHSS index > 10 had a significantly  higher  level of surface of TLR2  expression  over the observation period, while the largest difference in TLR4  expression  in the subgroups  was observed  on the 1st day of the disease (p < 0.05). Patients with ischemic stroke showed an increase  in TLR2 and TLR4 expression at the gene and protein level, compared to healthy  donors. These indices can be considered possible predictors for clinical  prognosis  of ischemic stroke.

Sign in / Sign up

Export Citation Format

Share Document