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2.
Nat Immunol ; 21(8): 950-961, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32572241

RESUMO

A contribution of epigenetic modifications to B cell tolerance has been proposed but not directly tested. Here we report that deficiency of ten-eleven translocation (Tet) DNA demethylase family members Tet2 and Tet3 in B cells led to hyperactivation of B and T cells, autoantibody production and lupus-like disease in mice. Mechanistically, in the absence of Tet2 and Tet3, downregulation of CD86, which normally occurs following chronic exposure of self-reactive B cells to self-antigen, did not take place. The importance of dysregulated CD86 expression in Tet2- and Tet3-deficient B cells was further demonstrated by the restriction, albeit not complete, on aberrant T and B cell activation following anti-CD86 blockade. Tet2- and Tet3-deficient B cells had decreased accumulation of histone deacetylase 1 (HDAC1) and HDAC2 at the Cd86 locus. Thus, our findings suggest that Tet2- and Tet3-mediated chromatin modification participates in repression of CD86 on chronically stimulated self-reactive B cells, which contributes, at least in part, to preventing autoimmunity.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Antígeno B7-2/imunologia , Proteínas de Ligação a DNA/imunologia , Dioxigenases/imunologia , Proteínas Proto-Oncogênicas/imunologia , Animais , Doenças Autoimunes/imunologia , Epigênese Genética/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
3.
Mol Psychiatry ; 28(5): 1932-1945, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36882500

RESUMO

The BTBR T+Itpr3tf/J (BTBR/J) strain is one of the most valid models of idiopathic autism, serving as a potent forward genetics tool to dissect the complexity of autism. We found that a sister strain with an intact corpus callosum, BTBR TF/ArtRbrc (BTBR/R), showed more prominent autism core symptoms but moderate ultrasonic communication/normal hippocampus-dependent memory, which may mimic autism in the high functioning spectrum. Intriguingly, disturbed epigenetic silencing mechanism leads to hyperactive endogenous retrovirus (ERV), a mobile genetic element of ancient retroviral infection, which increases de novo copy number variation (CNV) formation in the two BTBR strains. This feature makes the BTBR strain a still evolving multiple-loci model toward higher ASD susceptibility. Furthermore, active ERV, analogous to virus infection, evades the integrated stress response (ISR) of host defense and hijacks the transcriptional machinery during embryonic development in the BTBR strains. These results suggest dual roles of ERV in the pathogenesis of ASD, driving host genome evolution at a long-term scale and managing cellular pathways in response to viral infection, which has immediate effects on embryonic development. The wild-type Draxin expression in BTBR/R also makes this substrain a more precise model to investigate the core etiology of autism without the interference of impaired forebrain bundles as in BTBR/J.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Retrovirus Endógenos , Gravidez , Feminino , Humanos , Animais , Camundongos , Retrovirus Endógenos/genética , Variações do Número de Cópias de DNA , Transtorno Autístico/etiologia , Prosencéfalo/metabolismo , Corpo Caloso/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/complicações , Camundongos Endogâmicos
4.
Mol Ecol ; 31(14): 3859-3870, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35691011

RESUMO

Sex chromosomes constantly exist in a dynamic state of evolution: rapid turnover and change of heterogametic sex during homomorphic state, and often stepping out to a heteromorphic state followed by chromosomal decaying. However, the forces driving these different trajectories of sex chromosome evolution are still unclear. The Japanese frog Glandirana rugosa is one taxon well suited to the study on these driving forces. The species has two different heteromorphic sex chromosome systems, XX-XY and ZZ-ZW, which are separated in different geographic populations. Both XX-XY and ZZ-ZW sex chromosomes are represented by chromosome 7 (2n = 26). Phylogenetically, these two systems arose via hybridization between two ancestral lineages of West Japan and East Japan populations, of which sex chromosomes are homomorphic in both sexes and to date have not yet been identified. Identification of the sex chromosomes will give us important insight into the mechanisms of sex chromosome evolution in this species. Here, we used a high-throughput genomic approach to identify the homomorphic XX-XY sex chromosomes in both ancestral populations. Sex-linked DNA markers of West Japan were aligned to chromosome 1, whereas those of East Japan were aligned to chromosome 3. These results reveal that at least two turnovers across three different sex chromosomes 1, 3 and 7 occurred during evolution of this species. This finding raises the possibility that cohabitation of the two different sex chromosomes from ancestral lineages induced turnover to another new one in their hybrids, involving transition of heterogametic sex and evolution from homomorphy to heteromorphy.


Assuntos
Cromossomos Sexuais , Processos de Determinação Sexual , Animais , Anuros/genética , Evolução Molecular , Feminino , Marcadores Genéticos , Masculino , Ranidae/genética , Cromossomos Sexuais/genética , Processos de Determinação Sexual/genética
5.
Dev Growth Differ ; 64(6): 279-289, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35881001

RESUMO

Sex chromosomes in poikilothermal vertebrates are characterized by rapid and diverse evolution at the species or population level. Our previous study revealed that the Taiwanese frog Odorrana swinhoana (2n = 26) has a unique system of multiple sex chromosomes created by three sequential translocations among chromosomes 1, 3, and 7. To reveal the evolutionary history of sex chromosomes in the Odorrana species complex, we first identified the original, homomorphic sex chromosomes, prior to the occurrence of translocations, in the ancestral-type population of O. swinhoana. Then, we extended the investigation to a closely related Japanese species, Odorrana utsunomiyaorum, which is distributed on two small islands. We used a high-throughput nuclear genomic approach to analyze single-nucleotide polymorphisms and identify the sex-linked markers. Those isolated from the O. swinhoana ancestral-type population were found to be aligned to chromosome 1 and showed male heterogamety. In contrast, almost all the sex-linked markers isolated from O. utsunomiyaorum were heterozygous in females and homozygous in males and were aligned to chromosome 9. Morphologically, we confirmed chromosome 9 to be heteromorphic in females, showing a ZZ-ZW sex determination system, in which the W chromosomes were heterochromatinized in a stripe pattern along the chromosome axis. These results indicated that after divergence of the two species, the ancestral homomorphic sex chromosome 1 underwent highly rapid and diverse evolution, i.e., sequential translocations with two autosomes in O. swinhoana, and turnover to chromosome 9 in O. utsunomiyaorum, with a transition from XY to ZW heterogamety and change to heteromorphy.


Assuntos
Cromossomos Sexuais , Processos de Determinação Sexual , Animais , Anuros/genética , Evolução Molecular , Feminino , Genoma , Masculino , Ranidae/genética , Cromossomos Sexuais/genética , Processos de Determinação Sexual/genética
6.
Nature ; 539(7629): 378-383, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27806374

RESUMO

Sleep is conserved from invertebrates to vertebrates, and is tightly regulated in a homeostatic manner. The molecular and cellular mechanisms that determine the amount of rapid eye movement sleep (REMS) and non-REMS (NREMS) remain unknown. Here we identify two dominant mutations that affect sleep and wakefulness by using an electroencephalogram/electromyogram-based screen of randomly mutagenized mice. A splicing mutation in the Sik3 protein kinase gene causes a profound decrease in total wake time, owing to an increase in inherent sleep need. Sleep deprivation affects phosphorylation of regulatory sites on the kinase, suggesting a role for SIK3 in the homeostatic regulation of sleep amount. Sik3 orthologues also regulate sleep in fruitflies and roundworms. A missense, gain-of-function mutation in the sodium leak channel NALCN reduces the total amount and episode duration of REMS, apparently by increasing the excitability of REMS-inhibiting neurons. Our results substantiate the use of a forward-genetics approach for studying sleep behaviours in mice, and demonstrate the role of SIK3 and NALCN in regulating the amount of NREMS and REMS, respectively.


Assuntos
Canais Iônicos/genética , Mutagênese , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas Serina-Treonina Quinases/genética , Sono/genética , Sono/fisiologia , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Sequência Conservada , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Eletroencefalografia , Eletromiografia , Homeostase/genética , Canais Iônicos/química , Canais Iônicos/metabolismo , Proteínas de Membrana , Camundongos , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Splicing de RNA/genética , Distribuição Aleatória , Privação do Sono , Sono REM/genética , Sono REM/fisiologia , Fatores de Tempo , Vigília/genética , Vigília/fisiologia
7.
Cytogenet Genome Res ; 161(1-2): 23-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33735859

RESUMO

The sex chromosomes of most anuran amphibians are characterized by homomorphy in both sexes, and evolution to heteromorphy rarely occurs at the species or geographic population level. Here, we report sex chromosome heteromorphy in geographic populations of the Japanese Tago's brown frog complex (2n = 26), comprising Rana sakuraii and R. tagoi. The sex chromosomes of R. sakuraii from the populations in western Japan were homomorphic in both sexes, whereas chromosome 7 from the populations in eastern Japan were heteromorphic in males. Chromosome 7 of R. tagoi, which is distributed close to R. sakuraii in eastern Japan, was highly similar in morphology to the Y chromosome of R. sakuraii. Based on this and on mitochondrial gene sequence analysis, we hypothesize that in the R. sakuraii populations from eastern Japan the XY heteromorphic sex chromosome system was established by the introduction of chromosome 7 from R. tagoi via interspecies hybridization. In contrast, chromosome 13 of R. tagoi from the 2 large islands in western Japan, Shikoku and Kyushu, showed a heteromorphic pattern of constitutive heterochromatin distribution in males, while this pattern was homomorphic in females. Our study reveals that sex chromosome heteromorphy evolved independently at the geographic lineage level in this species complex.


Assuntos
Mitocôndrias/genética , Ranidae/genética , Cromossomos Sexuais , Animais , Bandeamento Cromossômico , DNA Mitocondrial/genética , Feminino , Geografia , Japão , Cariotipagem , Funções Verossimilhança , Filogenia , RNA Ribossômico 16S/genética , Especificidade da Espécie , Cromossomo Y
8.
J Pineal Res ; 71(2): e12748, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34085306

RESUMO

The hormone melatonin is synthesized from serotonin by two enzymatic reactions (AANAT and ASMT/HIOMT) in the pineal gland following a circadian rhythm with low levels during the day and high levels at night. The robust nightly peak of melatonin secretion is an output signal of the circadian clock to the whole organism. However, so far the regulatory roles of endogenous melatonin in mammalian biological rhythms and physiology processes are poorly understood. Here, we establish congenic mouse lines (>N10 generations) that are proficient or deficient in melatonin synthesis (AH+/+ or AH-/- mice, respectively) on the C57BL/6J genetic background by crossing melatonin-proficient MSM/Ms with C57BL/6J. AH+/+ mice displayed robust nightly peak of melatonin secretion and had significantly higher levels of pineal and plasma melatonin vs AH-/- mice. Using this mice model, we investigated the role of endogenous melatonin in regulating multiple biological rhythms, physiological processes, and rhythmic behaviors. In the melatonin-proficient (AH+/+) mice, the rate of re-entrainment of wheel-running activity was accelerated following a 6-hour phase advance of dark onset when comparted with AH-/- mice, suggesting a role of endogenous melatonin in facilitating clock adjustment. Further in the AH+/+ mice, there was a significant decrease in body weight, gonadal weight and reproductive performance, and a significant increase in daily torpor (a hypothermic and hypometabolic state lasting only hours during adverse conditions). Endogenous melatonin, however, had no effect in the modulation of the diurnal rhythm of 2-[125 I]-iodomelatonin receptor expression in the SCN, free-running wheel behavior in constant darkness, life span, spontaneous homecage behaviors, and various types of social-emotional behaviors. The findings also shed light on the role of endogenous melatonin in mice domestication and provide new insights into melatonin's action in reducing energy expenditure during a food shortage. In summary, the congenic mice model generated in this study offers a significant advantage toward understanding of the role of endogenous melatonin in regulating melatonin receptor-mediated rhythm behaviors and physiological functions.


Assuntos
Melatonina , Glândula Pineal , Animais , Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Glândula Pineal/metabolismo , Reprodução
9.
J Neurochem ; 154(1): 25-40, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31587290

RESUMO

Vanishing white matter disease (VWM) is an autosomal recessive neurological disorder caused by mutation(s) in any subunit of eukaryotic translation initiation factor 2B (eIF2B), an activator of translation initiation factor eIF2. VWM occurs with mutation of the genes encoding eIF2B subunits (EIF2B1, EIF2B2, EIF2B3, EIF2B4, and EIF2B5). However, little is known regarding the underlying pathogenetic mechanisms or how to treat patients with VWM. Here we describe the identification and detailed analysis of a new spontaneous mutant mouse harboring a point mutation in the Eif2b5 gene (p.Ile98Met). Homozygous Eif2b5I98M mutant mice exhibited a small body, abnormal gait, male and female infertility, epileptic seizures, and a shortened lifespan. Biochemical analyses indicated that the mutant eIF2B protein with the Eif2b5I98M mutation decreased guanine nucleotide exchange activity on eIF2, and the level of the endoplasmic reticulum stress marker activating transcription factor 4 was elevated in the 1-month-old Eif2b5I98M brain. Histological analyses indicated up-regulated glial fibrillary acidic protein immunoreactivity in the astrocytes of the Eif2b5I98M forebrain and translocation of Bergmann glia in the Eif2b5I98M cerebellum, as well as increased mRNA expression of an endoplasmic reticulum stress marker, C/EBP homologous protein. Disruption of myelin and clustering of oligodendrocyte progenitor cells were also indicated in the white matter of the Eif2b5I98M spinal cord at 8 months old. Our data show that Eif2b5I98M mutants are a good model for understanding VWM pathogenesis and therapy development. Cover Image for this issue: doi: 10.1111/jnc.14751.


Assuntos
Modelos Animais de Doenças , Fator de Iniciação 2B em Eucariotos/genética , Leucoencefalopatias/genética , Leucoencefalopatias/patologia , Neuroglia/patologia , Animais , Encéfalo/patologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação Puntual
10.
Rinsho Ketsueki ; 61(2): 103-109, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32147608

RESUMO

A 69-year-old woman with leukocytopenia and thrombocytopenia was referred to our hospital. Her bone marrow comprised 70.5% abnormal promyelocytes that were positive for myeloperoxidase/CD33/CD117 and CD13 (dim) and negative for CD2/CD34/CD56 and HLA-DR. Chromosome analysis of the bone marrow showed t (12;17;15) (p13;q21;q22), and fluorescence in situ hybridization revealed the PML-RARA fusion signal only on the derivative chromosome 15. The patient was diagnosed with acute promyelocytic leukemia (APL) with PML-RARA and was treated using all-trans retinoic acid (ATRA). In peripheral blood (PB), PML-RARA-positive polymorphonuclear cells (PMNs) appeared on the second week and became negative on the sixth week after treatment, whereas PML-RARA-negative PMNs started to increase in number on the sixth week. Molecular remission was confirmed on the 10th week. Quantitative evaluation of the differentiated leukemic cells of APL and recovered cells from normal hematopoiesis in PB can provide useful information for a safer induction therapy. No significant difference was noted in the kinetics of the leukemic cells under ATRA treatment as well as in the clinical features between our patient without RARA-PML and those with t (15;17), which is a cytogenetic evidence for the critical role of PML-RARA in the pathogenesis of APL.


Assuntos
Leucemia Promielocítica Aguda , Idoso , Cromossomos Humanos , Feminino , Humanos , Hibridização in Situ Fluorescente , Cinética , Leucemia Promielocítica Aguda/genética , Proteínas de Fusão Oncogênica , Translocação Genética , Tretinoína
11.
Haematologica ; 104(7): 1417-1421, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30523053

RESUMO

The so-called "double-hit" and "double-protein-expression" lymphoma with MYC and BCL2 rearrangements is a rare, mature B-cell neoplasm characterized by a germinal center B-cell phenotype, abundant protein expression of MYC and BCL2, rapid disease progression, and a poor prognosis. In this study, we showed the potential benefit of the BCL2 inhibitor venetoclax in the treatment of this disease. Immunohistochemical studies of the lymphoma tissues confirmed that overexpression of MYC and BCL2 was observed more frequently in this subtype than in other germinal center B-cell-like diffuse large B-cell lymphomas. In contrast, another pro-survival protein MCL1 was less expressed in this subtype, even when compared with its expression in the non-"double-hit" and "double-protein-expression" type. Furthermore, in vitro studies using two "double-hit" and "double-protein-expression" lymphoma-derived cell lines, Karpas231 and OCI-Ly8, clearly showed that a low concentration of venetoclax, but not the MCL1 inhibitor S63845, was sufficient to induce apoptosis in the two lines, compared with in other germinal center B-cell-derived cell lines, BJAB and SU-DHL10. These results indicate that the survival of this type of lymphoma depends predominantly on BCL2 rather than on MCL1. Unexpectedly, we found that venetoclax not only disrupts the interaction between BCL2 and the pro-apoptotic protein BIM, but also leads to dephosphorylation of BCL2 and further downregulates MCL1 protein expression, probably through modulation of the protein phosphatase 2A B56α activity in Karpas231 and OCI-Ly8. Indeed, a low concentration of venetoclax induced substantial apoptosis in the primary lymphoma cells, regardless of high protein expression of MCL1 associated with venetoclax resistance. Venetoclax clearly triggers the signal transduction related to BCL2 and MCL1 in "double-hit" and "double-protein-expression" lymphoma cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Rearranjo Gênico , Linfoma Difuso de Grandes Células B/patologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Sulfonamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Células Tumorais Cultivadas
12.
Cancer Sci ; 109(4): 1254-1262, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29363227

RESUMO

Peripheral T- or natural killer (NK)-cell lymphomas are rare and difficult-to-recognize diseases. It remains arduous to distinguish between NK cell- and cytotoxic T-lymphocyte-derived lymphomas through routine histological evaluation. To clarify the cells of origin, we focused on NK-cell receptors and examined the expression using immunohistochemistry in 22 cases with T- and NK-cell neoplasms comprising angioimmunoblastic T-cell lymphoma, anaplastic lymphoma kinase (ALK)-positive and -negative anaplastic large-cell lymphomas, extranodal NK/T-cell lymphoma, nasal type, monomorphic epitheliotropic intestinal T-cell lymphoma, aggressive NK-cell leukemia, and other peripheral T-cell lymphomas. Inhibitory receptor leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1) was detected in 14 (64%) cases, whereas activating receptors DNAM1, NKp46, and NKG2D were expressed in 7 (32%), 9 (41%), and 5 (23%) cases, respectively. Although LILRB1 was detected regardless of the disease entity, the activating NK-cell receptors were expressed predominantly in TIA-1-positive neoplasms (DNAM1, 49%; NKp46, 69%; and NKG2D, 38%). In addition, NKp46 and NKG2D were detected only in NK-cell neoplasms and cytotoxic T-lymphocyte-derived lymphomas including monomorphic epitheliotropic intestinal T-cell lymphoma. One Epstein-Barr virus-harboring cytotoxic T-lymphocyte-derived lymphoma mimicking extranodal NK/T-cell lymphoma, nasal type lacked these NK-cell receptors, indicating different cell origin from NK and innate-like T cells. Furthermore, NKG2D expression showed a negative impact on survival among the 22 examined cases, which mainly received the standard chemotherapy regimen (log-rank test, P = .024). We propose that the presence of activating NK-cell receptors may provide new insights into understanding peripheral T-cell lymphomas and characterizing them as innate-like T-cell neoplasm.


Assuntos
Células Matadoras Naturais/metabolismo , Linfoma de Células T Periférico/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Linfócitos T Citotóxicos/metabolismo , Adulto , Idoso , Quinase do Linfoma Anaplásico , Antígenos de Diferenciação de Linfócitos T/metabolismo , Feminino , Humanos , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Linfoma Anaplásico de Células Grandes/metabolismo , Masculino , Pessoa de Meia-Idade , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Adulto Jovem
13.
Genome Res ; 25(8): 1125-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26129709

RESUMO

The germline mutation rate is an important parameter that affects the amount of genetic variation and the rate of evolution. However, neither the rate of germline mutations in laboratory mice nor the biological significance of the mutation rate in mammalian populations is clear. Here we studied genome-wide mutation rates and the long-term effects of mutation accumulation on phenotype in more than 20 generations of wild-type C57BL/6 mice and mutator mice, which have high DNA replication error rates. We estimated the base-substitution mutation rate to be 5.4 × 10(-9) (95% confidence interval = 4.6 × 10(-9)-6.5 × 10(-9)) per nucleotide per generation in C57BL/6 laboratory mice, about half the rate reported in humans. The mutation rate in mutator mice was 17 times that in wild-type mice. Abnormal phenotypes were 4.1-fold more frequent in the mutator lines than in the wild-type lines. After several generations, the mutator mice reproduced at substantially lower rates than the controls, exhibiting low pregnancy rates, lower survival rates, and smaller litter sizes, and many of the breeding lines died out. These results provide fundamental information about mouse genetics and reveal the impact of germline mutation rates on phenotypes in a mammalian population.


Assuntos
Animais de Laboratório/genética , Mutação em Linhagem Germinativa , Camundongos/genética , Animais , Animais de Laboratório/fisiologia , Evolução Molecular , Feminino , Genoma , Tamanho da Ninhada de Vivíparos , Camundongos/classificação , Camundongos/fisiologia , Taxa de Mutação , Fenótipo , Gravidez , Taxa de Gravidez , Seleção Genética
14.
Mamm Genome ; 29(9-10): 663-669, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30171338

RESUMO

Male reproductive anomalies are widely distributed among mammals, and male factors are estimated to contribute to approximately 50% of cases of human infertility. The B10.M/Sgn (B10.M) mouse strain exhibits two adverse reproductive phenotypes: severe teratospermia and male subfertility. Although teratospermia is known to be heritable, the relationship between teratospermia and male subfertility has not been well characterized. The fertility of B10.M male mice is considerably lower (~ 30%) than that of standard laboratory mouse strains (~ 70%). To genetically analyze male subfertility, F2 males were produced by intercrossing the F1 progeny of female B10.M and male C3H/HeN mice. The fertility of each F2 male mouse was assessed based on the outcomes of matings with five females. Statistical analysis of correlations between the two reproductive phenotypes (teratospermia and subfertility) in F2 males (n = 177) revealed that teratospermia is not the cause of male subfertility. Quantitative trait loci (QTL) analysis of the male subfertility phenotype (n = 128) using GigaMUGA markers mapped one significant QTL peak to chromosome 4 at 62.9 centimorgans (cM) with a logarithm of odds score of 11.81 (P < 0.05). We named the QTL locus Mfsf1 (male factor subfertility 1). Further genetic analysis using recombinant males restricted the physical area to 1.53 megabasepairs (Mbp), encompassing 22 protein-coding genes. In addition, we found one significant QTL and one indicative QTL on chromosome 5 and 12, respectively, that interacted with the Mfsf1 locus. Our results demonstrate that genetic dissection of male subfertility in the B10.M strain is a useful model for characterizing the complex genetic mechanisms underlying reproduction and infertility.


Assuntos
Mapeamento Cromossômico , Infertilidade Masculina/genética , Locos de Características Quantitativas/genética , Animais , Epistasia Genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Modelos Genéticos , Fenótipo , Característica Quantitativa Herdável , Software
15.
Mod Pathol ; 31(2): 313-326, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28984304

RESUMO

Most high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements are aggressive B-cell lymphomas. Occasional double-hit follicular lymphomas have been described but the clinicopathological features of these tumors are not well known. To clarify the characteristics of double-hit follicular lymphomas, we analyzed 10 cases of double-hit follicular lymphomas and 15 cases of high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements for clinicopathological and genome-wide copy-number alterations and copy-neutral loss-of-heterozygosity profiles. For double-hit follicular lymphomas, the median age was 67.5 years (range: 48-82 years). The female/male ratio was 2.3. Eight patients presented with advanced clinical stage. The median follow-up time was 20 months (range: 1-132 months). At the end of the follow-up, 8 patients were alive, 2 patients were dead including 1 patient with diffuse large B-cell lymphoma transformation. Rearrangements of MYC/BCL2, MYC/BCL6, and MYC/BCL2/BCL6 were seen in 8, 1, and 1 cases, respectively. The partner of MYC was IGH in 6 cases. There were no cases of histological grade 1, 4 cases of grade 2, 5 cases of grade 3a, and 1 case of grade 3b. Two cases of grade 3a exhibited immunoblast-like morphology. Immunohistochemistry demonstrated 9 cases with ≥50% MYC-positive cells. There was significant difference in MYC intensity (P=0.00004) and MIB-1 positivity (P=0.001) between double-hit follicular lymphomas and high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements. The genome profile of double-hit follicular lymphomas was comparable with conventional follicular lymphomas (GSE67385, n=198) with characteristic gains of 2p25.3-p11.1, 7p22.3-q36.3, 12q11-q24.33, and loss of 18q21.32-q23 (P<0.05). In comparison with high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements, double-hit follicular lymphomas had fewer copy-number alterations and minimal common region of gain at 2p16.1 (70%), locus also significant against conventional follicular lymphomas (P=0.0001). In summary, double-hit follicular lymphomas tended to be high-grade histology, high MYC protein expression, high MYC/IGH fusion, and minimal common region of gain at 2p16.1. Double-hit follicular lymphomas seemed to be a different disease from high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements and have an indolent clinical behavior similar to follicular lymphomas without MYC rearrangement.


Assuntos
Rearranjo Gênico , Linfoma de Células B/patologia , Linfoma Folicular/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-myc/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Linfoma de Células B/genética , Linfoma Folicular/genética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Fenótipo
16.
Mol Ecol ; 27(20): 4078-4089, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30086193

RESUMO

Sex-determining mechanisms change repeatedly throughout evolution, and it is difficult to track this continual process. The Japanese soil-frog Glandirana rugosa is a remarkable evolutionary witness to the ongoing process of the evolution of sex-determining modes. The two geographic groups, designated XY and Neo-ZW, have homologous sex chromosomes, yet display opposite types of sex chromosomes, XX-XY and ZZ-ZW, respectively. These two groups are sympatric at the edges of their respective ranges in Central Japan. In this study, we discovered molecular evidence that the eastern part of the Neo-ZW group (Neo-ZW2 subgroup), which is found near the sympatric area, shares mitochondrial haplotypes with the XY group. By analysing single nucleotide polymorphism (SNP) loci, we have also discovered that the representative nuclear genome of the Neo-ZW2 subgroup shares allele clusters with both the XY group and another part of the Neo-ZW group (Neo-ZW1 subgroup), indicating a hybrid origin of the Neo-ZW2. Further analysis of sex-linked SNP loci revealed that the alleles on the W chromosomes of the Neo-ZW2 were derived mostly from X chromosomes, while alleles on the Z chromosomes originated from the Z chromosomes of the Neo-ZW1 subgroup and partly from the Y chromosomes of the XY group. Our study revealed that admixture of the two opposite sex-chromosome systems reconstructed a female heterogametic system by recycling the X chromosomes into new W chromosomes. This work offers an illustrative example of how de novo sex-chromosome systems can arise by recycling material from ancestral sex chromosomes.


Assuntos
Cromossomos Sexuais/genética , Animais , Anuros , Evolução Molecular , Feminino , Masculino , Polimorfismo de Nucleotídeo Único/genética , Processos de Determinação Sexual/genética , Processos de Determinação Sexual/fisiologia , Cromossomo Y/genética
17.
Acta Haematol ; 140(2): 121-127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30227394

RESUMO

The prognosis for patients who experience hemostatic complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is poor. However, no report has investigated disseminated intravascular coagulation (DIC) caused by the complications of allo-HSCT without infection. Recombinant human soluble thrombomodulin (rhTM) was used to treat 12 episodes of DIC (n = 10; group 1) caused by allo-HSCT complications such as acute graft-versus-host disease (aGVHD) or thrombotic microangiopathy (TMA), and the clinical outcomes were compared with those of historical controls (n = 9; group 2) treated for DIC without rhTM. In group 1, the mean DIC score was significantly improved after using rhTM. Fibrinogen degeneration product (FDP), C-reactive protein (CRP), and the inflammatory cytokine high-mobility group box 1 (HMGB1) were also significantly decreased. Serial changes from the baseline values of platelet counts and levels of FDP were significantly better in group 1 than in group 2. The recovery rate from DIC was significantly higher in group 1 than in group 2. These findings suggest that rhTM is effective against both DIC and systemic inflammatory complications after allo-HSCT.


Assuntos
Coagulação Intravascular Disseminada/terapia , Transplante de Células-Tronco Hematopoéticas , Adulto , Idoso , Proteína C-Reativa/análise , Coagulação Intravascular Disseminada/tratamento farmacológico , Coagulação Intravascular Disseminada/mortalidade , Feminino , Doença Enxerto-Hospedeiro/etiologia , Proteína HMGB1/sangue , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Trombomodulina/genética , Trombomodulina/metabolismo , Trombomodulina/uso terapêutico , Microangiopatias Trombóticas/etiologia , Transplante Homólogo , Adulto Jovem
18.
Rinsho Ketsueki ; 59(3): 269-274, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29618683

RESUMO

A 73-year-old man with left parotid gland swelling over 2 months was referred to our hospital in March 201X. Purpura on the lower legs had been recurrent for >20 years. Biopsy of the parotid gland demonstrated diffuse infiltration of abnormal lymphocytes that were negative for CD10 and positive for CD19, CD20, and κ-chain. The Ki-67 positivity was <10%; lymphoepithelial lesions were observed. The patient was diagnosed with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Chromosome analysis revealed t (X;14) (p11.2;q32), and fluorescence in situ hybridization (FISH) of metaphase spreads showed three signals of the immunoglobulin heavy chain (IGH) gene on the derivative chromosomes X and 14, besides the normal chromosome 14. CT findings of parotid glands were suggestive of Sjogren syndrome, and biopsy of the purpura on the leg demonstrated leukocytoclastic vasculitis. In the literature, only seven patients with lymphoma and t (X;14) translocation have been reported. Of these, five patients had MALT lymphoma, one had nodal marginal zone lymphoma, and one had diffuse large B-cell lymphoma. In all patients, lymphoma evolved from previous autoimmune diseases. It is suggested that MALT lymphoma with the t (X;14) translocation forms a new entity of lymphoma.


Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico , Vasculite Leucocitoclástica Cutânea/patologia , Idoso , Cromossomos Humanos Par 14/genética , Cromossomos Humanos X/genética , Humanos , Hibridização in Situ Fluorescente , Linfoma de Zona Marginal Tipo Células B/genética , Masculino , Translocação Genética
19.
BMC Clin Pathol ; 17: 21, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29151814

RESUMO

BACKGROUND: B-cell lymphomas harboring the 8q24/MYC plus 18q21/BCL2 translocations are now referred to as high grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (HGBL-MBR). Although HGBL-MBR is frequently found in cases with diffuse large B-cell lymphoma or Burkitt lymphoma-like B-cell lymphoma, acute lymphoblastic leukemia (ALL)-like disease of HGBL-MBR (AL-HGBL-MBR) has been reported incidentally. CASE PRESENTATION: A 69-year-old Japanese woman developed remittent fever and increasing systemic bone pain. The bone marrow examination revealed that more than 90% of nuclear cells were blastoid cells, which were positive for CD10, CD19, CD20, and surface IgMκ and negative for terminal deoxynucleotidyl transferase (TdT). Cytogenetic studies confirmed that the patient had de novo AL-HGBL-MBR with the extra copies of MYC and loss of chromosome 17p. She showed resistance to chemoimmunotherapy and died seven months after the diagnosis. The literature review identified further 47 de novo AL-HGBL-MBR cases within the last 32 years. The median age was 61 years (range, 27 - 86); the male/female ratio was 2.0. Thirty-eight cases (79%) presented a clinical picture of ALL at diagnosis; 14 (36%) of 39 available cases showed central nervous system involvement. Loss of 17p and translocations at 2p12-13, 3q27, 9p13 were frequently observed as additional cytogenetic abnormalities. Although the median survival of 46 available cases was only five months (range, 0.1-18), rituximab use significantly improved the survival of AL-HGBL-MBR (log-rank test, P = 0.0294). CONCLUSION: Our patient and most reported de novo AL-HGBL-MBR cases showed resistance to conventional chemoimmunotherapy and disastrous consequences. AL-HGBL-MBL is a rare, but should be considered a distinct clinical condition in HGBL-MBR. Other therapeutic strategies, such as using inhibitors of MYC and BCL2, are needed to overcome the chemoresistance of AL-HGBL-MBR.

20.
Rinsho Ketsueki ; 58(1): 3-8, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28190862

RESUMO

A 69-year-old man diagnosed with leukocytosis was referred to our hospital in July 201X. The patient was diagnosed as having a myelodysplastic/myeloproliferative neoplasm. However, he presented with leukemia 2 months later. Chromosomal analysis of a bone marrow sample documented that this patient had a normal karyotype. The patient was successfully treated with idarubicin and cytarabine, and he underwent three courses of consolidation therapy. However, he suffered a relapse in May of the following year. A cytogenetic analysis revealed the presence of a t (3;21) (q13;q22) translocation, and fluorescence in situ hybridization of metaphase spreads detected three signals corresponding to the runt related transcription factor 1 (RUNX1) on the derivative chromosomes 3 and 21, besides the normal chromosome 21. Chromosomal translocations in leukemia often involve genes encoding transcription factors, and the RUNX1 is a common target for such translocations. To the best of our knowledge, this is a novel variant of the RUNX1 translocation. Identifying genes associated with translocations in leukemia contributes to novel insights into the mechanisms of disease progression and chemotherapy resistance and also facilitates the development of molecularly targeted therapies.


Assuntos
Cromossomos Humanos Par 21 , Cromossomos Humanos Par 3 , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Translocação Genética , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Evolução Fatal , Humanos , Cariotipagem , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino
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