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1.
Nature ; 613(7944): 460-462, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653563

RESUMO

Most structural and evolutionary properties of galaxies strongly rely on the stellar initial mass function (IMF), namely the distribution of the stellar mass formed in each episode of star formation1-4. The IMF shapes the stellar population in all stellar systems, and so has become one of the most fundamental concepts of modern astronomy. Both constant and variable IMFs across different environments have been claimed despite a large number of theoretical5-7 and observational efforts8-15. However, the measurement of the IMF in Galactic stellar populations has been limited by the relatively small number of photometrically observed stars, leading to high uncertainties12-16. Here we report a star-counting result based on approximately 93,000 spectroscopically observed M-dwarf stars, an order of magnitude more than previous studies, in the 100-300 parsec solar neighbourhood. We find unambiguous evidence of a variable IMF that depends on both metallicity and stellar age. Specifically, the stellar population formed at early times contains fewer low-mass stars compared with the canonical IMF, independent of stellar metallicities. In more recent times, however, the proportion of low-mass stars increases with stellar metallicity. The variable abundance of low-mass stars in our Milky Way establishes a powerful benchmark for models of star formation and can heavily affect results in Galactic chemical-enrichment modelling, mass estimation of galaxies and planet-formation efficiency.

2.
Mol Cell ; 72(6): 1021-1034.e4, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30472193

RESUMO

The dynamic transcriptional regulation and interactions of human germlines and surrounding somatic cells during folliculogenesis remain unknown. Using RNA sequencing (RNA-seq) analysis of human oocytes and corresponding granulosa cells (GCs) spanning five follicular stages, we revealed unique features in transcriptional machinery, transcription factor networks, and reciprocal interactions in human oocytes and GCs that displayed developmental-stage-specific expression patterns. Notably, we identified specific gene signatures of two cell types in particular developmental stage that may reflect developmental competency and ovarian reserve. Additionally, we uncovered key pathways that may concert germline-somatic interactions and drive the transition of primordial-to-primary follicle, which represents follicle activation. Thus, our work provides key insights into the crucial features of the transcriptional regulation in the stepwise folliculogenesis and offers important clues for improving follicle recruitment in vivo and restoring fully competent oocytes in vitro.


Assuntos
Comunicação Celular/genética , Células da Granulosa/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Reserva Ovariana/genética , Transcriptoma , Adulto , Animais , Biologia Computacional , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Humanos , Camundongos , Folículo Ovariano/citologia , Transdução de Sinais/genética , Análise de Célula Única , Especificidade da Espécie , Transcrição Gênica , Adulto Jovem
3.
Genome Res ; 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35760561

RESUMO

Clinical exome sequencing has yielded extensive disease-related missense single-nucleotide variants (SNVs) of uncertain significance, leading to diagnostic uncertainty. KCNQ4 is one of the most commonly responsible genes for autosomal dominant nonsyndromic hearing loss. According to the gnomAD cohort, approximately one in 100 people harbors missense variants in KCNQ4 (missense variants with minor allele frequency > 0.1% were excluded), but most are of unknown consequence. To prospectively characterize the function of all 4085 possible missense SNVs of human KCNQ4, we recorded the whole-cell currents using the patch-clamp technique and categorized 1068 missense SNVs as loss of function, as well as 728 loss-of-function SNVs located in the transmembrane domains. Further, to mimic the heterozygous condition in Deafness nonsyndromic autosomal dominant 2 (DFNA2) patients caused by KCNQ4 variants, we coexpressed loss-of-function variants with wild-type KCNQ4 and found 516 variants showed impaired or only partially rescued heterogeneous channel function. Overall, our functional classification is highly concordant with the auditory phenotypes in Kcnq4 mutant mice and the assessments of pathogenicity in clinical variant interpretations. Taken together, our results provide strong functional evidence to support the pathogenicity classification of newly discovered KCNQ4 missense variants in clinical genetic testing.

4.
PLoS Genet ; 18(8): e1010310, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939513

RESUMO

Chromosomal mosaicism is common throughout human pre- and post-implantation development. However, the incidence and characteristics of mosaicism in human blastocyst remain unclear. Concerns and confusions still exist regarding the interpretation of chromosomal mosaicism on preimplantation genetic testing for aneuploidy (PGT-A) results and embryo development. Here, we aimed to estimate the genetic concordance between trophectoderm (TE), inner cell mass (ICM) and the corresponding human embryonic stem cells (hESCs), and to explore the characteristics of mosaicism in human blastocyst and hESCs on a single cell level. The single cell sequencing results of TE cells indicated that 65.71% of the blastocysts were mosaic (23 in 35 embryos), while the ICM sequencing results suggested that 60.00% of the blastocysts were mosaic (9 in 15 embryos). The incidence of mosaicism for the corresponding hESCs was 33.33% (2 in 6 embryos). No significant difference was observed between the mosaic rate of TE and that of ICM. However, the mosaic rate of the corresponding hESCs was significantly lower than that of TE and ICM cells, suggesting that the incidence of mosaicism may decline during embryonic development. Upon single cell sequencing, we found several "complementary" copy number variations (CNVs) that were usually not revealed in clinical PGT-A which used multi-cell DNA sequencing (or array analysis). This indicates the potential diagnostic risk of PGT-A based multi-cell analysis routinely in clinical practice. This study provided new insights into the characteristics, and considerable influences, of mosaicism on human embryo development, as well as the clinical risks of PGT-A based on multi-cell biopsies and bulk DNA assays.


Assuntos
Mosaicismo , Diagnóstico Pré-Implantação , Aneuploidia , Blastocisto , Variações do Número de Cópias de DNA/genética , Feminino , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Gravidez , Diagnóstico Pré-Implantação/métodos
5.
Cogn Affect Behav Neurosci ; 24(3): 517-526, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38273105

RESUMO

Sleep deprivation (SD) negatively affects many cognitive functions, such as language performance. However, what remains unclear is whether and how SD affects the language-related brain network based on gender and age differences. The current study of 86 healthy adults used resting-state functional magnetic resonance imaging (rs-fMRI) to measure language-related functional connectivity after full sleep or partial SD. Gender and age differences in functional connectivity were assessed across four linguistic aspects: phonetics, morphology, semantics, and syntax. The results showed that SD can affect the connectivity status of language-related brain networks, especially syntax-related networks. Furthermore, the influence of SD on the functional connectivity in language-related networks differed between male and female groups, and between younger and older groups. Specifically, there were gender differences in the temporal association cortex and age differences in the parietal association cortex, during full sleep versus partial SD. These findings highlight changes in the brain's functional connectivity in response to SD as a potential source of gender and age differences in brain function.


Assuntos
Mapeamento Encefálico , Encéfalo , Idioma , Imageamento por Ressonância Magnética , Caracteres Sexuais , Privação do Sono , Humanos , Masculino , Feminino , Adulto , Privação do Sono/fisiopatologia , Privação do Sono/diagnóstico por imagem , Adulto Jovem , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Vias Neurais/fisiopatologia , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem , Pessoa de Meia-Idade , Envelhecimento/fisiologia , Adolescente
6.
Plant Physiol ; 192(2): 1603-1620, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36879425

RESUMO

Pectin methylesterification in guard cell (GC) walls plays an important role in stomatal development and stomatal response to external stimuli, and pectin methylesterase inhibitors (PMEIs) modulate pectin methylesterification by inhibition of pectin methylesterase (PME). However, the function of PMEIs has not been reported in stomata. Here, we report the role of Arabidopsis (Arabidopsis thaliana) PECTIN METHYLESTERASE INHIBITOR18 in stomatal dynamic responses to environmental changes. PMEI18 mutation increased pectin demethylesterification and reduced pectin degradation, resulting in increased stomatal pore size, impaired stomatal dynamics, and hypersensitivity to drought stresses. In contrast, overexpression of PMEI18 reduced pectin demethylesterification and increased pectin degradation, causing more rapid stomatal dynamics. PMEI18 interacted with PME31 in plants, and in vitro enzymatic assays demonstrated that PMEI18 directly inhibits the PME activity of PME31 on pectins. Genetic interaction analyses suggested that PMEI18 modulates stomatal dynamics mainly through inhibition of PME31 on pectin methylesterification in cell walls. Our results provide insight into the molecular mechanism of the PMEI18-PME31 module in stomatal dynamics and highlight the role of PMEI18 and PME31 in stomatal dynamics through modulation of pectin methylesterification and distribution in GC walls.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/metabolismo , Pectinas/metabolismo
7.
Plant Physiol ; 192(1): 205-221, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36756926

RESUMO

Flowering time is one of the most important agronomic traits affecting the adaptation and yield of rice (Oryza sativa). Heading date 1 (Hd1) is a key factor in the photoperiodic control of flowering time. In this study, two basic helix-loop-helix (bHLH) transcription factors, Hd1 Binding Protein 1 (HBP1) and Partner of HBP1 (POH1) were identified as transcriptional regulators of Hd1. We generated knockout mutants of HBP1 and ectopically expressed transgenic lines of the two bHLH transcription factors and used these lines to investigate the roles of these two factors in regulating flowering time. HBP1 physically associated with POH1 forming homo- or heterodimers to perform their functions. Both HBP1 and POH1 bound directly to the cis-acting elements located in the promoter of Hd1 to activate its expression. CRISPR/Cas9-generated knockout mutations of HBP1, but not POH1 mutations, promoted earlier flowering time; conversely, HBP1 and POH1 overexpression delayed flowering time in rice under long-day and short-day conditions by activating the expression of Hd1 and suppressing the expression of Early heading date 1 (Ehd1), Heading date 3a (Hd3a), and Rice Flowering locus T 1 (RFT1), thus controlling flowering time in rice. Our findings revealed a mechanism for flowering time control through transcriptional regulation of Hd1 and laid theoretical and practical foundations for improving the growth period, adaptation, and yield of rice.


Assuntos
Flores , Oryza , Oryza/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fotoperíodo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Reprod Biomed Online ; 49(3): 103991, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38936339

RESUMO

RESEARCH QUESTION: Does routine clinical practice require an increase in the resolution of preimplantation genetic testing for aneuploidies (PGT-A) to detect segmental aneuploidies ≤5 Mb? DESIGN: This retrospective study analysed 963 trophectoderm biopsies from 346 couples undergoing PGT between 2019 and 2023. Segmental aneuploidies ≥1 Mb were reported. The characteristics, clinical interpretation and concordance of segmental aneuploidies ≤5 Mb were analysed. RESULTS: The incidence of segmental aneuploidies was 15.1% (145/963) in blastocysts, with segmental aneuploidies of ≤5 Mb accounting for 2.3% (22/963). The size of the segmental aneuploidies showed a skewed distribution. Segmental aneuploidies ≤5 Mb were found to occur more frequently on the q arm of the chromosome, compared with the p arm. Losses of ≤5 Mb segmental aneuploidies were more prevalent than gains, with 17 deletions compared with 5 duplications. Of the segmental aneuploidies, 63.6% (14/22) ≤5 Mb were de novo, and 50.0% (7/14) of de-novo segmental aneuploidies were pathogenic/likely pathogenic (P/LP) copy number variations, accounting for 0.7% of 963 blastocysts. For blastocysts carrying ≤5 Mb segmental aneuploidies, a re-analysis of back-up biopsy samples showed that 35.7% of de-novo segmental aneuploidies (5/14) were not detected in the back-up samples. Cases were reported in which prenatal diagnosis (amniocentesis) revealed the absence of embryonic ≤5 Mb segmental aneuploidies detected at the blastocyst stage. CONCLUSIONS: The incidence of P/LP de-novo ≤5 Mb segmental aneuploidies in human blastocysts is extremely low. There is no compelling need to increase the resolution of PGT-A to 5 Mb in routine clinical practice.

9.
BMC Pregnancy Childbirth ; 24(1): 230, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566020

RESUMO

BACKGROUND: Cumulative live birth rate (CLBR) is considered as the most important endpoint for assessing the probability of having a baby in a complete in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment cycle. Many previous studies have focused on the association between thyroid autoimmunity (TAI) and live birth rate after first embryo transfer cycle, however, evidence on whether the presence of TAI affects the CLBR is lacking. The purpose of this study is to investigate the impact of TAI on the CLBR in a complete IVF/ICSI cycle. METHODS: This retrospective study included 12,796 women who underwent their first IVF/ICSI treatment between January 2019 and February 2021. Based on the levels of thyroid antibodies, 2,603 women were assigned to the TAI group, and 10,193 women were assigned to the control group. Subgroup analysis was performed according to the different causes of infertility (including male factor only, ovulation disorder, tubal factor, endometriosis and unexplained infertility) and different types and titres of thyroid antibodies. The primary outcome in this study was CLBR, which included live births from the fresh embryo transfer cycle and all subsequent frozen-thawed embryo transfer cycles performed before December 2021. RESULTS: There was no significant difference in the CLBR between the TAI and control groups, even after adjusting for relevant confounders including age, body mass index, cause of infertility, thyroid function, protocols of controlled ovarian stimulation, type of transfer (fresh vs. frozen), type of transferred embryo (cleavage-stage embryo vs. blastocyst), and fertilization method (IVF vs. ICSI) (cumulative live birth: 50.6% vs. 52.1%, OR 0.94, 95% CI 0.86-1.02, adjusted OR 0.97, 95%CI 0.89-1.06). Subgroup analysis showed that no significant difference was observed in CLBR between the TAI and control groups for all causes of infertility, except for infertility attributed to endometriosis. Among women with endometriosis, the CLBR was significantly lower in the TAI group than that in the control group; however, this difference was not significant after adjusting for potential confounders including age, body mass index, thyroid function, protocols of controlled ovarian stimulation, type of transfer (fresh vs. frozen), type of transferred embryo (cleavage-stage embryo vs. blastocyst), and fertilization method (IVF vs. ICSI) (cumulative live births: 43.1% vs. 51.0%, OR 0.73, 95% CI 0.53-0.99, adjusted OR 0.74, 95% CI 0.53-1.02). Another subgroup analysis demonstrated that the type and titre of thyroid antibody did not affect CLBR in women with TAI. CONCLUSIONS: In our study, there was no significant difference in the CLBR between women with TAI and those without TAI, which suggests that TAI did not affect the chances of having a baby in a complete IVF/ICSI treatment cycle.


Assuntos
Endometriose , Infertilidade , Gravidez , Masculino , Feminino , Humanos , Injeções de Esperma Intracitoplásmicas/métodos , Coeficiente de Natalidade , Estudos Retrospectivos , Autoimunidade , Glândula Tireoide , Sêmen , Fertilização in vitro/métodos , Nascido Vivo/epidemiologia , Taxa de Gravidez
10.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34848538

RESUMO

Auditory transduction is mediated by chordotonal (Cho) neurons in Drosophila larvae, but the molecular identity of the mechanotransduction (MET) channel is elusive. Here, we established a whole-cell recording system of Cho neurons and showed that two transient receptor potential vanilloid (TRPV) channels, Nanchung (NAN) and Inactive (IAV), are essential for MET currents in Cho neurons. NAN and IAV form active ion channels when expressed simultaneously in S2 cells. Point mutations in the pore region of NAN-IAV change the reversal potential of the MET currents. Particularly, residues 857 through 990 in the IAV carboxyl terminus regulate the kinetics of MET currents in Cho neurons. In addition, TRPN channel NompC contributes to the adaptation of auditory transduction currents independent of its ion-conduction function. These results indicate that NAN-IAV, rather than NompC, functions as essential pore-forming subunits of the native auditory transduction channel in Drosophila and provide insights into the gating mechanism of MET currents in Cho neurons.


Assuntos
Proteínas de Drosophila/metabolismo , Canais Iônicos/metabolismo , Mecanotransdução Celular/fisiologia , Neurônios/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Potenciais de Ação/fisiologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Proteínas de Drosophila/genética , Drosophila melanogaster , Fenômenos Eletrofisiológicos , Regulação da Expressão Gênica , Canais Iônicos/genética , Larva , Técnicas de Patch-Clamp , Mutação Puntual , Canais de Potencial de Receptor Transitório/genética
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(1): 101-105, 2024 Jan 10.
Artigo em Zh | MEDLINE | ID: mdl-38171568

RESUMO

OBJECTIVE: To determine the karyotype of a patient with mosaicism complex structural aberration of chromosome 18. METHODS: A male patient with a 2-year history of infertility presented at the Center of Reproductive Medicine of the Third Hospital of Peking University in October 2019 was selected as the study subject. Clinical data of the patient was collected. Peripheral blood sample was taken for chromosomal karyotyping, copy number variation (CNV) analysis and fluorescence in situ hybridization (FISH) assay. Semen sample was taken for single sperm CNV analysis. RESULTS: The patient was found to have a karyotype of mos 47,XY,del(18)(q21q23),+r(18)(q21q23)[84]/46,XY,del(18)(q21q23)[9]/48,XY,del(18)(q21q23),+r(18)(q21q23)×2[6]/47,XY,del(18)(q21q23),+r(18)(q21q23×2)[1].ish 47,XY,del(18)(q21q23),+r(18)(q21q23)[84]/46,XY,del(18)(q21q23)[9]/48,XY,del(18)(q21q23),+r(18)(q21q23)×2[6]/47,XY,del(18)(q21q23),+r(18)(q21q23×2)[1]del(18)(q21q23)(D18Z1+,18p+,18q+,WCP18+),r(18)(q21q23)(WCP18+),r(18)(q21q23×2)(WCP18+). No pathogenic CNV was identified. Sequencing of 20 single sperms showed that 1 sperm was normal, 1 had yielded no result, 9 had harbored del(18q), 7 had harbored dup(18q)×2, and 2 had harbored dup(18q)×3. The dup/del fragments had both spanned approximately 33 Mb. CONCLUSION: It is rare for carriers of complex structural and numerical abnormalities of chromosome 18 to have a normal phenotype. Based on the accurate cytogenetic and molecular analyses and the single sperm CNV analysis, the influence of the aberrant karyotype on the gametogenesis may be evaluated.


Assuntos
Cromossomos Humanos Par 18 , Mosaicismo , Masculino , Humanos , Hibridização in Situ Fluorescente , Cromossomos Humanos Par 18/genética , Variações do Número de Cópias de DNA , Sêmen , Cariótipo
12.
BMC Immunol ; 24(1): 19, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430199

RESUMO

BACKGROUND: Allergen-specific immunotherapy (AIT) is a causative treatment in allergic rhinitis (AR), comprising long-term allergen administration and over three years of treatment. This study is carried out for revealing the mechanisms and key genes of AIT in AR. METHODS: The present study utilized online Gene Expression Omnibus (GEO) microarray expression profiling dataset GSE37157 and GSE29521 to analyze the hub genes changes related to AIT in AR. Based on limma package, differential expression analysis for the two groups (samples of allergic patients prior to AIT and samples of allergic patients undergoing AIT) was performed to obtain differentially expressed genes (DEGs). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs were conducted using DAVID database. A Protein-Protein Interaction network (PPI) was built and a significant network module was acquired by using Cytoscape software (Cytoscape, 3.7.2). Utilizing the miRWalk database, we identified potential gene biomarkers, constructed interaction networks of target genes and microRNAs (miRNAs) using Cytoscape software, and explore the cell type-specific expression patterns of these genes in peripheral blood using publicly available single-cell RNA sequencing data (GSE200107). Finally, we are using PCR to detect changes in the hub genes that are screened using the above method in peripheral blood before and after AIT treatment. RESULTS: GSE37157 and GSE29521 included 28 and 13 samples, respectively. A total of 119 significantly co-upregulated DEGs and 33 co-downregulated DEGs were obtained from two datasets. The GO and KEGG analyses demonstrated that protein transport, positive regulation of apoptotic process, Natural killer cell mediated cytotoxicity, T cell receptor signaling pathway, TNF signaling pathway, B cell receptor signaling pathway and Apoptosis may be potential candidate therapeutic targets for AIT of AR. From the PPI network, 20 hub genes were obtained. Among them, the PPI sub-networks of CASP3, FOXO3, PIK3R1, PIK3R3, ATF4, and POLD3 screened out from our study have been identified as reliable predictors of AIT in AR, especially the PIK3R1. CONCLUSION: Our analysis has identified novel gene signatures, thereby contributing to a more comprehensive understanding of the molecular mechanisms underlying AIT in the treatment of AR.


Assuntos
MicroRNAs , Rinite Alérgica , Humanos , Rinite Alérgica/genética , Rinite Alérgica/terapia , Fatores de Transcrição , MicroRNAs/genética , Alérgenos/genética , Imunoterapia , Fosfatidilinositol 3-Quinases
13.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34097004

RESUMO

Transcriptomic and epigenetic alterations during early embryo development have been proven to play essential roles in regulating the cell fate. Nowadays, advances in single-cell transcriptomics and epigenomics profiling techniques provide large volumes of data for understanding the molecular regulatory mechanisms in early embryos and facilitate the investigation of assisted reproductive technology as well as preimplantation genetic testing. However, the lack of integrated data collection and unified analytic procedures greatly limits their usage in scientific research and clinical application. Hence, it is necessary to establish a database integrating the regulatory information of human and mouse early embryos with unified analytic procedures. Here, we introduce DevOmics (http://devomics.cn/), which contains normalized gene expression, DNA methylation, histone modifications (H3K4me3, H3K9me3, H3K27me3, H3K27ac), chromatin accessibility and 3D chromatin architecture profiles of human and mouse early embryos spanning six developmental stages (zygote, 2cell, 4cell, 8cell, morula and blastocyst (ICM, TE)). The current version of DevOmics provides Search and Advanced Search for retrieving genes a researcher is interested in, Analysis Tools including the differentially expressed genes (DEGs) analysis for acquiring DEGs between different types of samples, allelic explorer for displaying allele-specific gene expression as well as epigenetic modifications and correlation analysis for showing the dynamic changes in different layers of data across developmental stages, as well as Genome Browser and Ortholog for visualization. DevOmics offers a user-friendly website for biologists and clinicians to decipher molecular regulatory mechanisms of human and mouse early embryos.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário , Genômica/métodos , Software , Animais , Mapeamento Cromossômico , Metilação de DNA , Epigenômica/métodos , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , Interface Usuário-Computador , Navegador
14.
J Hum Genet ; 68(12): 813-821, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37592134

RESUMO

Hereditary tumor syndromes have garnered substantial attention due to their adverse effects on both the physical and psychological health of patients, as well as the elevated risk of transmission to subsequent generations. This has prompted a growing interest in exploring preimplantation genetic testing (PGT) as a treatment option to mitigate and eliminate these impacts. Several studies have demonstrated that de novo variants have become a great cause of many hereditary tumor syndromes, which introduce certain difficulties to PGT. In the absence of adequate genetic linkage information (parents and offspring), haplotype construction seems unrealizable. In the study, researchers used single sperm or affected embryos as proband to perform single-nucleotide polymorphism linkage analysis for cases with de novo variants. For complicated variants, the strategy that sperm combined with embryo detection will increase accuracy while avoiding the limitations and potential failures of using a single detection material. The study recruited 11 couples with male de novo carriers, including 3 tumor types and 4 genes. To date, 4 couples have been clinically confirmed as pregnant and three healthy babies have been born. The results of amniocentesis or umbilical cord blood verification were consistent with the results of PGT-M. The study aims to introduce the application of the PGT-M strategy in hereditary tumor syndromes.


Assuntos
Diagnóstico Pré-Implantação , Gravidez , Feminino , Masculino , Humanos , Diagnóstico Pré-Implantação/métodos , Predisposição Genética para Doença , Sêmen , Testes Genéticos/métodos , Aneuploidia , Ligação Genética
15.
Reproduction ; 166(2): 117-124, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37252832

RESUMO

In brief: Whether sperm DNA fragmentation (SDF) affects embryo development and clinical outcomes is still controversial, which limits the utility of SDF testing in assisted reproductive technology management. This study demonstrates that high SDF is associated with the incidence of segmental chromosomal aneuploidy and increased paternal whole chromosomal aneuploidies. Abstract: We aimed to investigate the correlation of sperm DNA fragmentation (SDF) with the incidence and paternal origin of whole and segmental chromosomal aneuploidies of embryos at the blastocyst stage. A retrospective cohort study was conducted with a total of 174 couples (women aged 35 years or younger) who underwent 238 cycles (including 748 blastocysts) of preimplantation genetic testing for monogenic diseases (PGT-M). All subjects were divided into two groups based on the sperm DNA fragmentation index (DFI) level: low DFI (<27%) and high DFI (≥27%). The rates of euploidy, whole chromosomal aneuploidy, segmental chromosomal aneuploidy, mosaicism, parental origin of aneuploidy, fertilization, cleavage, and blastocyst formation were compared between low- and high-DFI groups. We found no significant differences in fertilization, cleavage, or blastocyst formation between the two groups. Compared to that in the low-DFI group, segmental chromosomal aneuploidy rate was significantly higher in the high-DFI group (11.57% vs 5.83%, P = 0.021; OR: 2.32, 95% CI: 1.10-4.89, P = 0.028). The whole chromosomal embryonic aneuploidy of paternal origin was significantly higher in cycles with high DFI than in cycles with low DFI (46.43% vs 23.33%, P = 0.018; OR: 4.32, 95% CI: 1.06-17.66, P = 0.041). However, the segmental chromosomal aneuploidy of paternal origin was not significantly different between the two groups (71.43% vs 78.05%, P = 0.615; OR: 1.01, 95% CI: 0.16-6.40, P = 0.995). In conclusion, our results suggested that high SDF was associated with the incidence of segmental chromosomal aneuploidy and increased paternal whole chromosomal aneuploidies in embryos.


Assuntos
Diagnóstico Pré-Implantação , Gravidez , Humanos , Masculino , Feminino , Incidência , Fragmentação do DNA , Estudos Retrospectivos , Diagnóstico Pré-Implantação/métodos , Fertilização in vitro/métodos , Sêmen , Aneuploidia , Blastocisto , Mosaicismo , Espermatozoides
16.
Proc Natl Acad Sci U S A ; 117(44): 27218-27223, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33067388

RESUMO

Most proteins have evolved to spontaneously fold into native structure and specifically bind with their partners for the purpose of fulfilling biological functions. According to Darwin, protein sequences evolve through random mutations, and only the fittest survives. The understanding of how the evolutionary selection sculpts the interaction patterns for both biomolecular folding and binding is still challenging. In this study, we incorporated the constraint of functional binding into the selection fitness based on the principle of minimal frustration for the underlying biomolecular interactions. Thermodynamic stability and kinetic accessibility were derived and quantified from a global funneled energy landscape that satisfies the requirements of both the folding into the stable structure and binding with the specific partner. The evolution proceeds via a bowl-like evolution energy landscape in the sequence space with a closed-ring attractor at the bottom. The sequence space is increasingly reduced until this ring attractor is reached. The molecular-interaction patterns responsible for folding and binding are identified from the evolved sequences, respectively. The residual positions participating in the interactions responsible for folding are highly conserved and maintain the hydrophobic core under additional evolutionary constraints of functional binding. The positions responsible for binding constitute a distributed network via coupling conservations that determine the specificity of binding with the partner. This work unifies the principles of protein binding and evolution under minimal frustration and sheds light on the evolutionary design of proteins for functions.


Assuntos
Sequência de Aminoácidos/genética , Ligação Proteica/genética , Proteínas/genética , Fenômenos Biofísicos , Cinética , Modelos Moleculares , Fenômenos Físicos , Conformação Proteica , Dobramento de Proteína , Proteínas/química , Termodinâmica
17.
J Assist Reprod Genet ; 40(11): 2659-2668, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37730945

RESUMO

PURPOSE: While efforts have been made to establish blastocyst grading systems in the past decades, little research has examined the quality of biopsy specimens. This study is the first to correlate the morphology of biopsied trophectoderm (TE) cells to their quality and subsequent genetic testing results of preimplantation genetic testing (PGT), through an innovative Morphological Analysis and Genetic Integrality Criterion (MAGIC) system. METHODS: Biopsied TE cells were first evaluated according to the MAGIC procedure, followed by whole-genome amplification (WGA) and library construction, and then sequenced using the Illumina X Ten Platform. Copy number variation (CNV) and allele drop-out (ADO) rates as well as test failure rates were compared and analyzed. RESULTS: Our data explores the relationship between TE cell morphology and its quality and final genetic testing outcome, which is established based on the MAGIC system. MAGIC guarantees that only high- or good-quality TE cells are used for genetic testing to generate excellent data uniformity and lower ADO rates. Low-quality cells containing biopsied TE cell mass are responsible for the "background noise" of CNV analysis. CONCLUSION: The MAGIC application has effectively decreased the false-positive mosaicism, hence to ensure the stability and veracity of detection results, to avoid misdiagnoses, and to improve accuracy, as well as to avoid re-biopsy procedures. The study also contributes to understand how the IVF laboratory and the molecular biology laboratory depend on each other to achieve good-quality PGT results, which are clinically relevant for the patients.


Assuntos
Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Diagnóstico Pré-Implantação/métodos , Variações do Número de Cópias de DNA/genética , Testes Genéticos/métodos , Blastocisto/patologia , Mosaicismo , Biópsia/métodos , Aneuploidia
18.
Biochem Biophys Res Commun ; 595: 54-61, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-35101664

RESUMO

The therapeutic effect of CAR-T is often accompanied by sCRS, which is the main obstacle to the promotion of CAR-T therapy. The JAK1/2 inhibitor ruxolitinib has recently been confirmed as clinically effective in maintaining control over sCRS, however, its mechanism remains unclear. In this study, we firstly revealed that ruxolitinib significantly inhibited the proliferation of CAR-T cells without damaging viability, and induced an efficacy-favored differentiation phenotype. Second, ruxolitinib reduced the level of cytokine release not only from CAR-T cells, but also from other cells in the immune system. Third, the cytolytic activity of CAR-T cells was restored once the ruxolitinib was removed; however, the cytokines released from the CAR-T cells maintained an inhibited state to some degree. Finally, ruxolitinib significantly reduced the proliferation rate of CAR-T cells in vivo without affecting the therapeutic efficacy after withdrawal at the appropriate dose. We demonstrated pre-clinically that ruxolitinib interferes with both CAR-T cells and the other immune cells that play an important role in triggering sCRS reactions. This work provides useful and important scientific data for clinicians on the question of whether ruxolitinib has an effect on CAR-T cell function loss causing CAR-T treatment failure when applied in the treatment of sCRS, the answer to which is of great clinical significance.


Assuntos
Proliferação de Células/efeitos dos fármacos , Síndrome da Liberação de Citocina/prevenção & controle , Nitrilas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/efeitos dos fármacos , Animais , Linfoma de Burkitt/complicações , Linfoma de Burkitt/terapia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Síndrome da Liberação de Citocina/complicações , Humanos , Imunoterapia Adotiva/métodos , Inibidores de Janus Quinases/farmacologia , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Análise de Sobrevida , Linfócitos T/citologia , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
19.
Mol Hum Reprod ; 28(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34904654

RESUMO

Infertility has become a global health issue, with the number of people suffering from the disease increasing year by year, and ART offering great promise for infertility treatment. However, the regulation of early embryonic development is complicated and a series of processes takes place, including the maternal-to-zygotic transition. In addition, developmental arrest is frequently observed during human early embryonic development. In this study, we performed single-cell RNA sequencing on a biopsied blastomere from human eight-cell embryos and tracked the developmental potential of the remaining cells. To compare the sequencing results between different eight-cell embryos, we have combined the research data of this project with the data previously shared in the database and found that cells from the same embryo showed a higher correlation. Additionally, the transcriptome of embryos with blastocyst formation failure was significantly different from developed embryos, and the gene expression as well as cell signaling pathways related to embryonic development were also altered. In particular, the expression of some maternal and zygotic genes in the failed blastocyst formation group was significantly altered: the overall expression level of maternal genes was significantly higher in the failed blastocyst than the developed blastocyst group. In general, these findings provide clues for the causes of human embryonic arrest after the eight-cell stage, and they also provide new ideas for improving the success rate of ART in clinical practice.


Assuntos
Blastocisto , Desenvolvimento Embrionário , Blastocisto/metabolismo , Blastômeros , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Feminino , Humanos , Gravidez , Análise de Sequência de RNA
20.
Plant Physiol ; 187(4): 2820-2836, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34890462

RESUMO

The mechanical properties of guard cell (GC) walls are important for stomatal development and stomatal response to external stimuli. However, the molecular mechanisms of pectin synthesis and pectin composition controlling stomatal development and dynamics remain poorly explored. Here, we characterized the role of two Arabidopsis (Arabidopsis thaliana) galacturonosyltransferases, GAUT10 and GAUT11, in plant growth, stomatal development, and stomatal dynamics. GAUT10 and GAUT11 double mutations reduced pectin synthesis and promoted homogalacturonan (HG) demethylesterification and demethylesterified HG degradation, resulting in larger stomatal complexes and smaller pore areas, increased stomatal dynamics, and enhanced drought tolerance of plants. In contrast, increased GAUT10 or GAUT11 expression impaired stomatal dynamics and drought sensitivity. Genetic interaction analyses together with immunolabeling analyses suggest that the methylesterified HG level is important in stomatal dynamics, and pectin abundance with the demethylesterified HG level controls stomatal dimension and stomatal size. Our results provide insight into the molecular mechanism of GC wall properties in stomatal dynamics, and highlight the role of GAUT10 and GAUT11 in stomatal dimension and dynamics through modulation of pectin biosynthesis and distribution in GC walls.


Assuntos
Arabidopsis/fisiologia , Estômatos de Plantas/fisiologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis , Glucuronosiltransferase , Hexosiltransferases , Estômatos de Plantas/crescimento & desenvolvimento
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