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1.
Proc Natl Acad Sci U S A ; 121(12): e2318176121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483994

RESUMEN

Endogenous retroviruses (ERVs) are frequently reactivated in mammalian placenta. It has been proposed that ERVs contribute to shaping the gene regulatory network of mammalian trophoblasts, dominantly acting as species- and placental-specific enhancers. However, whether and how ERVs control human trophoblast development through alternative pathways remains poorly understood. Besides the well-recognized function of human endogenous retrovirus-H (HERVH) in maintaining pluripotency of early human epiblast, here we present a unique role of HERVH on trophoblast lineage development. We found that the LTR7C/HERVH subfamily exhibits an accessible chromatin state in the human trophoblast lineage. Particularly, the LTR7C/HERVH-derived Urothelial Cancer Associated 1 (UCA1), a primate-specific long non-coding RNA (lncRNA), is transcribed in human trophoblasts and promotes the proliferation of human trophoblast stem cells (hTSCs), whereas its ectopic expression compromises human trophoblast syncytialization coinciding with increased interferon signaling pathway. Importantly, UCA1 upregulation is detectable in placental samples from early-onset preeclampsia (EO-PE) patients and the transcriptome of EO-PE placenta exhibits considerable similarities to that of the syncytiotrophoblasts differentiated from UCA1-overexpressing hTSCs, supporting up-regulated UCA1 as a potential biomarker of this disease. Altogether, our data shed light on the versatile regulatory role of HERVH in early human development and provide a unique mechanism whereby ERVs exert a function in human placentation and placental syndromes.


Asunto(s)
Retrovirus Endógenos , ARN Largo no Codificante , Animales , Humanos , Embarazo , Femenino , Retrovirus Endógenos/genética , Retrovirus Endógenos/metabolismo , Placenta/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Trofoblastos/metabolismo , Placentación , Primates/genética , Mamíferos/genética
2.
Dev Biol ; 502: 39-49, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37437860

RESUMEN

As the source of embryonic stem cells (ESCs), inner cell mass (ICM) can form all tissues of the embryo proper, however, its role in early human lineage specification remains controversial. Although a stepwise differentiation model has been proposed suggesting the existence of ICM as a distinct developmental stage, the underlying molecular mechanism remains unclear. In the present study, we perform an integrated analysis on the public human preimplantation embryonic single-cell transcriptomic data and apply a trajectory inference algorithm to measure the cell plasticity. In our results, ICM population can be clearly discriminated on the dimension-reduced graph and confirmed by compelling evidences, thus validating the two-step hypothesis of lineage commitment. According to the branch probabilities and differentiation potential, we determine the precise time points for two lineage segregations. Further analysis on gene expression dynamics and regulatory network indicates that transcription factors including GSC, PRDM1, and SPIC may underlie the decisions of ICM fate. In addition, new human ICM marker genes, such as EPHA4 and CCR8 are discovered and validated by immunofluorescence. Given the potential clinical applications of ESCs, our analysis provides a further understanding of human ICM cells and facilitates the exploration of more unique characteristics in early human development.


Asunto(s)
Blastocisto , Transcriptoma , Humanos , Transcriptoma/genética , Linaje de la Célula/genética , Blastocisto/metabolismo , Embrión de Mamíferos , Diferenciación Celular/genética , Regulación del Desarrollo de la Expresión Génica
3.
Development ; 148(11)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34125190

RESUMEN

Loss-of-function mutations in multiple morphological abnormalities of the sperm flagella (MMAF)-associated genes lead to decreased sperm motility and impaired male fertility. As an MMAF gene, the function of fibrous sheath-interacting protein 2 (FSIP2) remains largely unknown. In this work, we identified a homozygous truncating mutation of FSIP2 in an infertile patient. Accordingly, we constructed a knock-in (KI) mouse model with this mutation. In parallel, we established an Fsip2 overexpression (OE) mouse model. Remarkably, KI mice presented with the typical MMAF phenotype, whereas OE mice showed no gross anomaly except for sperm tails with increased length. Single-cell RNA sequencing of the testes uncovered altered expression of genes related to sperm flagellum, acrosomal vesicle and spermatid development. We confirmed the expression of Fsip2 at the acrosome and the physical interaction of this gene with Acrv1, an acrosomal marker. Proteomic analysis of the testes revealed changes in proteins sited at the fibrous sheath, mitochondrial sheath and acrosomal vesicle. We also pinpointed the crucial motifs of Fsip2 that are evolutionarily conserved in species with internal fertilization. Thus, this work reveals the dosage-dependent roles of Fsip2 in sperm tail and acrosome formation.


Asunto(s)
Acrosoma/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Plasma Seminal/metabolismo , Cola del Espermatozoide/metabolismo , Animales , Fertilización , Homocigoto , Masculino , Proteínas de la Membrana , Ratones , Mutación , Fenotipo , Proteómica , Análisis de Secuencia de ARN , Motilidad Espermática , Espermatogénesis , Testículo
4.
Appl Environ Microbiol ; 90(7): e0071424, 2024 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-38940583

RESUMEN

Oligotrophic deep-water lakes are unique and sensitive ecosystems with limited nutrient availability. Understanding bacterial communities within these lakes is crucial for assessing ecosystem health, biogeochemical cycling, and responses to environmental changes. In this study, we investigated the seasonal and vertical dynamics of both free-living (FL) and particle-attached (PA) bacteria in Lake Fuxian, a typical oligotrophic deep freshwater lake in southeast China. Our findings revealed distinct seasonal and vertical dynamics of FL and PA bacterial communities, driven by similar physiochemical environmental factors. PA bacteria exhibited higher α- and ß-diversity and were enriched with Proteobacteria, Cyanobacteria, Firmicutes, Patescibacteria, Planctomycetota, and Verrucomicrobiota, while FL bacteria were enriched with Actinobacteria and Bacteroidota. FL bacteria showed enrichment in putative functions related to chemoheterotrophy and aerobic anoxygenic photosynthesis, whereas the PA fraction was enriched with intracellular parasites (mainly contributed by Rickettsiales, Chlamydiales, and Legionellales) and nitrogen metabolism functions. Deterministic processes predominantly shaped the assembly of both FL and PA bacterial communities, with stochastic processes playing a greater role in the FL fraction. Network analysis revealed extensive species interactions, with a higher proportion of positively correlated edges in the PA network, indicating mutualistic or cooperative interactions. Cyanobium, Comamonadaceae, and Roseomonas were identified as keystone taxa in the PA network, underscoring potential cooperation between autotrophic and heterotrophic bacteria in organic particle microhabitats. Overall, the disparities in bacterial diversity, community composition, putative function, and network characteristics between FL and PA fractions highlight their adaptation to distinct ecological niches within these unique lake ecosystems.IMPORTANCEUnderstanding the diversity of microbial communities, their assembly mechanisms, and their responses to environmental changes is fundamental to the study of aquatic microbial ecology. Oligotrophic deep-water lakes are fragile ecosystems with limited nutrient resources, rendering them highly susceptible to environmental fluctuations. Examining different bacterial types within these lakes offers valuable insights into the intricate mechanisms governing community dynamics and adaptation strategies across various scales. In our investigation of oligotrophic deep freshwater Lake Fuxian in China, we explored the seasonal and vertical dynamics of two bacterial types: free-living (FL) and particle-attached (PA). Our findings unveiled distinct patterns in the diversity, composition, and putative functions of these bacteria, all shaped by environmental factors. Understanding these subtleties provides insight into bacterial interactions, thereby influencing the overall ecosystem functioning. Ultimately, our research illuminates the adaptation and roles of FL and PA bacteria within these unique lake environments, contributing significantly to our broader comprehension of ecosystem stability and health.


Asunto(s)
Bacterias , Lagos , Microbiota , Lagos/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , China , Ecosistema , Estaciones del Año
5.
Microb Ecol ; 87(1): 96, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046558

RESUMEN

In aquatic ecosystems with low nutrient levels, organic aggregates (OAs) act as nutrient hotspots, hosting a diverse range of microbial species compared to those in the water column. Lake eutrophication, marked by intensified and prolonged cyanobacterial blooms, significantly impacts material and energy cycling processes, potentially altering the ecological traits of both free-living (FL) and particle-attached (PA) bacteria. However, the extent to which observed patterns of FL and PA bacterial diversity, community assembly, and stability extend to hypereutrophic lakes remains understudied. To address this gap, we investigated bacterial diversity, composition, assembly processes, and stability within hypereutrophic Lake Xingyun. Our results revealed that FL bacterial communities exhibited higher α-diversity than PA counterparts, coupled with discernible taxonomic compositions. Both bacterial communities showed distinct seasonality, influenced by cyanobacterial bloom intensity. Environmental factors accounted for 71.1% and 54.2% of the variation among FL and PA bacteria, respectively. The assembly of the PA bacterial community was predominantly stochastic, while FL assembly was more deterministic. The FL network demonstrated greater stability, complexity, and negative interactions, indicative of competitive relationships, while the PA network showed a prevalence of positive correlations, suggesting mutualistic interactions. Importantly, these findings differ from observations in oligotrophic, mesotrophic, and eutrophic lakes. Overall, this research provides valuable insights into the interplay among bacterial fractions, enhancing our understanding of nutrient status and cyanobacterial blooms in shaping bacterial communities.


Asunto(s)
Bacterias , Biodiversidad , Cianobacterias , Eutrofización , Lagos , Microbiota , Lagos/microbiología , Cianobacterias/genética , Cianobacterias/clasificación , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , ARN Ribosómico 16S/genética , Estaciones del Año , Ecosistema , China
6.
J Cell Physiol ; 238(7): 1580-1591, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37305966

RESUMEN

Poly(ADP-ribosyl)ation (PARylation) is an important post-translational modification of proteins that involves the transfer of ADP-ribose moieties, and plays important roles in many biological processes including DNA repair, gene expression, RNA processing, ribosome biogenesis, and protein translation. Though it is accepted that PARylation is crucial for oocyte maturation, little is known about how Mono(ADP-ribosyl)ation (MARylation) regulates this process. Here, we report that Parp12, a mon(ADP-ribosyl) transferase of poly(ADP-ribosyl) polymerase (PARP) family, was highly expressed at all stages of oocytes during meiotic maturation. At germinal vesicle (GV) stage, PARP12 was mainly distributed in cytoplasm. Interestingly, PARP12 formed granular aggregation near to spindle poles during metaphase I (MI) and metaphase II (MII). PARP12 depletion results in abnormal spindle organization and chromosome misalignment in mouse oocytes. Chromosome aneuploidy frequency in PARP12 knockdown oocytes was significantly increased. Importantly, PARP12 knockdown triggers activation of spindle assembly checkpoint as shown by active BUBR1 in PARP12-KD MI oocytes. Besides, F actin was significantly attenuated in PARP12-KD MI oocytes which may affect the asymmetric division process. Transcriptomic analysis demonstrated that PARP12 depletion disrupts transcriptome homeostasis. Collectively, our results showed that the maternally expressed mono(ADPribosyl) transferases PARP12 was essential for oocyte meiotic maturation in mouse.


Asunto(s)
Meiosis , Oocitos , Animales , Ratones , Cromosomas , Puntos de Control de la Fase M del Ciclo Celular , Metafase , Oocitos/metabolismo , Huso Acromático/genética , Huso Acromático/metabolismo
7.
Brain ; 145(1): 119-141, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-34077496

RESUMEN

Cerebral palsy is the most prevalent physical disability in children; however, its inherent molecular mechanisms remain unclear. In the present study, we performed in-depth clinical and molecular analysis on 120 idiopathic cerebral palsy families, and identified underlying detrimental genetic variants in 45% of these patients. In addition to germline variants, we found disease-related postzygotic mutations in ∼6.7% of cerebral palsy patients. We found that patients with more severe motor impairments or a comorbidity of intellectual disability had a significantly higher chance of harbouring disease-related variants. By a compilation of 114 known cerebral-palsy-related genes, we identified characteristic features in terms of inheritance and function, from which we proposed a dichotomous classification system according to the expression patterns of these genes and associated cognitive impairments. In two patients with both cerebral palsy and intellectual disability, we revealed that the defective TYW1, a tRNA hypermodification enzyme, caused primary microcephaly and problems in motion and cognition by hindering neuronal proliferation and migration. Furthermore, we developed an algorithm and demonstrated in mouse brains that this malfunctioning hypermodification specifically perturbed the translation of a subset of proteins involved in cell cycling. This finding provided a novel and interesting mechanism for congenital microcephaly. In another cerebral palsy patient with normal intelligence, we identified a mitochondrial enzyme GPAM, the hypomorphic form of which led to hypomyelination of the corticospinal tract in both human and mouse models. In addition, we confirmed that the aberrant Gpam in mice perturbed the lipid metabolism in astrocytes, resulting in suppressed astrocytic proliferation and a shortage of lipid contents supplied for oligodendrocytic myelination. Taken together, our findings elucidate novel aspects of the aetiology of cerebral palsy and provide insights for future therapeutic strategies.


Asunto(s)
Parálisis Cerebral , Discapacidad Intelectual , Animales , Parálisis Cerebral/genética , Cognición , Estudios de Cohortes , Comorbilidad , Humanos , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/genética , Ratones
8.
Planta Med ; 86(13-14): 967-975, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31766070

RESUMEN

The endophytic microbiome in medicinal plants is rich and diverse, but few studies have followed the endophytic microbiome of medicinal plants in different tissues with their growth. In this study, we examined the endophytic bacterial and fungal community structures associated with both the stem and root compartments of Dendrobium huoshanense at different growth years via high-throughput sequencing of 16S rRNA genes and nrDNA fragments of internal transcribed spacer regions. Results indicated that more diverse prokaryotic and fungal operational taxonomic units were detected in roots than in stems, and the alpha diversity of endophytic prokaryotic significantly differed among the 1-, 2-, and 3-year-old roots. The dominant bacterial phyla Proteobacteria Firmicutes, Actinobacteria, Bacteroidetes, and Acidobacteria, and fungal phyla Ascomycota, Basidiomycota, and Ascomycota were detected in the stems and roots with 3 growth years. Moreover, linear discriminant effect size analysis revealed 138 differentially abundant taxonomic clades in the bacterial level, and 197 in the fungal level in six groups. Our results provide evidence for endophytic microbiota communities depending on the tissues and growth years of D. huoshanense. The results from this study should be useful to better understand medicinal plant-microbe interactions.


Asunto(s)
Dendrobium , Microbiota , Endófitos/genética , Filogenia , Raíces de Plantas , ARN Ribosómico 16S/genética
9.
Front Pharmacol ; 15: 1421816, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175540

RESUMEN

Targeting the poly (ADP-ribose) polymerase (PARP) protein has shown therapeutic efficacy in cancers with homologous recombination (HR) deficiency due to BRCA mutations. Only small fraction of acute myeloid leukemia (AML) cells carry BRCA mutations, hence the antitumor efficacy of PARP inhibitors (PARPi) against this malignancy is predicted to be limited; however, recent preclinical studies have demonstrated that PARPi monotherapy has modest efficacy in AML, while in combination with cytotoxic chemotherapy it has remarkable synergistic antitumor effects. Immunotherapy has revolutionized therapeutics in cancer treatment, and PARPi creates an ideal microenvironment for combination therapy with immunomodulatory agents by promoting tumor mutation burden. In this review, we summarize the role of PARP proteins in DNA damage response (DDR) pathways, and discuss recent preclinical studies using synthetic lethal modalities to treat AML. We also review the immunomodulatory effects of PARPi in AML preclinical models and propose future directions for therapy in AML, including combined targeting of the DDR and tumor immune microenvironment; such combination regimens will likely benefit patients with AML undergoing PARPi-mediated cancer therapy.

10.
J Ethnopharmacol ; 330: 118067, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38636574

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Jingfang Baidu Powder (JFBDP) is a classic traditional Chinese medicine prescription. Although Jingfang Baidu powder obtained a general consensus on clinical efficacy in treating pneumonia, there were many Chinese herbal drugs in formula, complex components, and large oral dosage, which brings certain obstacles to clinical application. AIM OF THE STUDY: Therefore, screening of the active fraction that exerts anti-pneumonia helps improve the pharmaceutical preparation, improve the treatment compliance of patients, and further contribute to the clinical application, and the screening of the new active ingredients with anti-pneumonia. The histopathological observation, real-time quantitative PCR, western blotting, and immunofluorescence were applied to evaluate the anti-pneumonia efficacy of active fractions from JFBDP. RESULTS: Three fractions from JFBDP inhibit the gene expression of IL-1ß, IL-10, CCL3, CCL5, and CCL22 in lung tissue infected by Klebsiella at various degrees, and presented a good dose-response relationship. JF50 showed stronger anti-inflammatory effects among three fractions including JF30, JF50, and JF75. Besides, JF50 significantly reduced the protein expression of TLR4 and Myd88 in lung tissue infected with Klebsiella, and it also significantly inhibited p-ERK and p-NF-κB p65. JF50 significantly inhibits the protein expression of Caspase 3, Caspase 8, and Caspase 9 in lung tissue infected with Klebsiella at the dose of 25 mg/kg and 50 mg/kg. CONCLUSION: JF50 improves lung pathological damage in Klebsiella pneumonia mice by inhibiting the TLR4/Myd88/NF-κB-ERK signaling pathway, and inhibiting apoptosis of lung tissue cells. These findings provide a reference for further exploring the active substance basis of Jingfang Baidu Powder in treating bacterial pneumonia.


Asunto(s)
Medicamentos Herbarios Chinos , Infecciones por Klebsiella , Factor 88 de Diferenciación Mieloide , Polvos , Receptor Toll-Like 4 , Animales , Receptor Toll-Like 4/metabolismo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/uso terapéutico , Factor 88 de Diferenciación Mieloide/metabolismo , Ratones , Masculino , Infecciones por Klebsiella/tratamiento farmacológico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Antiinflamatorios/farmacología , Apoptosis/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/metabolismo , Klebsiella pneumoniae/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ratones Endogámicos C57BL
11.
Front Plant Sci ; 15: 1450716, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39372857

RESUMEN

Introduction: Understanding the microbial diversity and potential functional dynamics within the rhizocompartments of Dendrobium huoshanense is crucial for unraveling the plant-microbe interactions that influence its medicinal properties. Methods: This study is the first to characterize the microbiome associated with the rhizocompartments of D. huoshanense, including its cultivation medium, rhizosphere, rhizoplane, and root endosphere, using high-throughput sequencing and subsequent bioinformatic analysis. Results: Bacterial phylogenetic diversity was significantly higher in the endosphere than in the rhizosphere, while fungal α-diversity significantly decreased from the cultivation medium to the endosphere. Both bacterial and fungal niche widths decreased from the cultivation medium to the endosphere. ß-Diversity analysis revealed distinct spatial patterns in both bacterial and fungal communities across the rhizocompartments, with the most pronounced differences between the cultivation medium and the endosphere. Taxonomically, Proteobacteria and Ascomycota were predominant in the endosphere for bacterial and fungal communities, respectively. Functional predictions showed significant enrichment of pathways related to xenobiotics biodegradation, lipid metabolism, and nitrogen fixation in the endosphere, while functions associated with plant pathogens and saprotrophs were significantly reduced. Discussion: The results indicate a shift from generalist to specialist microbes from the cultivation medium to the endosphere, suggesting that D. huoshanense exerts strong selective pressure for endophytic fungi. Interestingly, a high proportion of fungi with unknown functions were found in the endosphere, highlighting an area for further research regarding the medicinal efficacy of D. huoshanense. Overall, this study provides foundational data for understanding the adaptive evolution of these microbial communities in response to specific microhabitats.

12.
iScience ; 27(5): 109748, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38706838

RESUMEN

We previously reported that loss of function of TYW1 led to cerebral palsy with severe intellectual disability through reduced neural proliferation. However, whether TYW1 loss affects neural differentiation is unknown. In this study, we first demonstrated that TYW1 loss blocked the formation of OHyW in tRNAphe and therefore affected the translation efficiency of UUU codon. Using the brain organoid model, we showed impaired neuron differentiation when TYW1 was depleted. Interestingly, retrotransposons were differentially regulated in TYW1-/- hESCs (human embryonic stem cells). In particular, one kind of human-specific endogenous retrovirus-K (HERVK/HML2), whose reactivation impaired human neurodevelopment, was significantly up-regulated in TYW1-/- hESCs. Consistently, a UUU codon-enriched protein, SMARCAD1, which was a key factor in controlling endogenous retroviruses, was reduced. Taken together, TYW1 loss leads to up-regulation of HERVK in hESCs by down-regulated SMARCAD1, thus impairing neuron differentiation.

13.
Pharmaceutics ; 15(9)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37765210

RESUMEN

The dependence of cancer cells on the DNA damage response (DDR) pathway for the repair of endogenous- or exogenous-factor-induced DNA damage has been extensively studied in various cancer types, including endometrial cancer (EC). Targeting one or more DNA damage repair protein with small molecules has shown encouraging treatment efficacy in preclinical and clinical models. However, the genes coding for DDR factors are rarely mutated in EC, limiting the utility of DDR inhibitors in this disease. In the current review, we recapitulate the functional role of the DNA repair system in the development and progression of cancer. Importantly, we discuss strategies that target DDR proteins, including PARP, CHK1 and WEE1, as monotherapies or in combination with cytotoxic agents in the treatment of EC and highlight the compounds currently being evaluated for their efficacy in EC in clinic. Recent studies indicate that the application of DNA damage agents in cancer cells leads to the activation of innate and adaptive immune responses; targeting immune checkpoint proteins could overcome the immune suppressive environment in tumors. We further summarize recently revolutionized immunotherapies that have been completed or are now being evaluated for their efficacy in advanced EC and propose future directions for the development of DDR-based cancer therapeutics in the treatment of EC.

14.
Stem Cell Res ; 67: 103022, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36630838

RESUMEN

NANOS3 is a zinc-finger containing RNA-binding protein that has been demonstrated to be highly expressed in human primordial germ cell(hPGC), thus NANOS3 can serve as a marker for hPGC development. Due to the ethical and technical restrictions, it is difficult to get primary human germline cells. Human primordial germ cell-like cells (hPGCLCs) generated from pluripotent stem cells is an excellent alternatives in human germ cell-related studies. This hESC line with an mCherry knock-in at the site before NANOS3's stop codon serves as a useful tool to learn human PGC specification.


Asunto(s)
Células Madre Embrionarias Humanas , Humanos , Células Madre Embrionarias Humanas/metabolismo , Sistemas CRISPR-Cas , Células Madre Embrionarias/metabolismo , Línea Celular , Células Germinativas/metabolismo , Diferenciación Celular , Proteínas de Unión al ARN/genética
15.
Cell Stem Cell ; 29(3): 400-418.e13, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-35143761

RESUMEN

Totipotent cells have more robust developmental potency than any other cell types, giving rise to both embryonic and extraembryonic tissues. Stable totipotent cell cultures and deciphering the principles of totipotency regulation would be invaluable to understand cell plasticity and lineage segregation in early development. Our approach of remodeling the pericentromeric heterochromatin and re-establishing the totipotency-specific broad H3K4me3 domains promotes the pluri-to-totipotency transition. Our protocol establishes a closer match of mouse 2-cell (2C) embryos than any other 2C-like cells. These totipotent-like stem cells (TLSCs) are stable in culture and possess unique molecular features of the mouse 2C embryo. Functionally, TLSCs are competent for germline transmission and give rise to both embryonic and extraembryonic lineages at high frequency. Therefore, TLSCs represent a highly valuable cell type for studies of totipotency and embryology.


Asunto(s)
Ensamble y Desensamble de Cromatina , Células Madre Totipotentes , Animales , Diferenciación Celular , Plasticidad de la Célula , Cromatina/metabolismo , Embrión de Mamíferos , Ratones
16.
Cell Rep ; 39(12): 110994, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35732112

RESUMEN

In human embryos, major zygotic genome activation (ZGA) initiates at the eight-cell (8C) stage. Abnormal ZGA leads to developmental defects and even contributes to the failure of human blastocyst formation or implantation. An in vitro cell model mimicking human 8C blastomeres would be invaluable to understanding the mechanisms regulating key biological events during early human development. Using the non-canonical promoter of LEUTX that putatively regulates human ZGA, we developed an 8C::mCherry reporter, which specifically marks the 8C state, to isolate rare 8C-like cells (8CLCs) from human preimplantation epiblast-like stem cells. The 8CLCs express a panel of human ZGA genes and have a unique transcriptome resembling that of the human 8C embryo. Using the 8C::mCherry reporter, we further optimize the chemical-based culture condition to increase and maintain the 8CLC population. Functionally, 8CLCs can self-organize to form blastocyst-like structures. The discovery and maintenance of 8CLCs provide an opportunity to recapitulate early human development.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Cigoto , Blastocisto , Desarrollo Embrionario/genética , Genoma , Humanos
17.
Cell Stem Cell ; 29(7): 1031-1050.e12, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35803225

RESUMEN

Reprogramming of H3K9me3-dependent heterochromatin is required for early development. How H3K9me3 is involved in early human development remains, however, largely unclear. Here, we resolve the temporal landscape of H3K9me3 during human preimplantation development and its regulation for diverse hominoid-specific retrotransposons. At the 8-cell stage, H3K9me3 reprogramming at hominoid-specific retrotransposons termed SINE-VNTR-Alu (SVA) facilitates interaction between certain promoters and SVA-derived enhancers, promoting the zygotic genome activation. In trophectoderm, de novo H3K9me3 domains prevent pluripotent transcription factors from binding to hominoid-specific retrotransposons-derived regulatory elements for inner cell mass (ICM)-specific genes. H3K9me3 re-establishment at SVA elements in the ICM is associated with higher transcription of DNA repair genes, when compared with naive human pluripotent stem cells. Our data demonstrate that species-specific reorganization of H3K9me3-dependent heterochromatin at hominoid-specific retrotransposons plays important roles during early human development, shedding light on how the epigenetic regulation for early development has evolved in mammals.


Asunto(s)
Heterocromatina , Retroelementos , Elementos Alu , Animales , Desarrollo Embrionario/genética , Epigénesis Genética , Humanos , Mamíferos , Retroelementos/genética
18.
Front Plant Sci ; 13: 849421, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35548303

RESUMEN

The mechanical strength of the stalk affects the lodging resistance and digestibility of the stalk in maize. The molecular mechanisms regulating the brittleness of stalks in maize remain undefined. In this study, we constructed the maize brittle stalk mutant (bk5) by crossing the W22:Mu line with the Zheng 58 line. The brittle phenotype of the mutant bk5 existed in all of the plant organs after the five-leaf stage. Compared to wild-type (WT) plants, the sclerenchyma cells of bk5 stalks had a looser cell arrangement and thinner cell wall. Determination of cell wall composition showed that obvious differences in cellulose content, lignin content, starch content, and total soluble sugar were found between bk5 and WT stalks. Furthermore, we identified 226 differentially expressed genes (DEGs), with 164 genes significantly upregulated and 62 genes significantly downregulated in RNA-seq analysis. Some pathways related to cellulose and lignin synthesis, such as endocytosis and glycosylphosphatidylinositol (GPI)-anchored biosynthesis, were identified by the Kyoto Encyclopedia of Gene and Genomes (KEGG) and gene ontology (GO) analysis. In bulked-segregant sequence analysis (BSA-seq), we detected 2,931,692 high-quality Single Nucleotide Polymorphisms (SNPs) and identified five overlapped regions (11.2 Mb) containing 17 candidate genes with missense mutations or premature termination codons using the SNP-index methods. Some genes were involved in the cellulose synthesis-related genes such as ENTH/ANTH/VHS superfamily protein gene (endocytosis-related gene) and the lignin synthesis-related genes such as the cytochrome p450 gene. Some of these candidate genes identified from BSA-seq also existed with differential expression in RNA-seq analysis. These findings increase our understanding of the molecular mechanisms regulating the brittle stalk phenotype in maize.

19.
Stem Cell Res ; 53: 102303, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33831647

RESUMEN

GPAM (glycerol-3-phosphateacyltransferase1) is a mitochondrial enzyme that catalyze an essential step in glycerolphospholipids and triacylglycerol biosynthesis process. Loss-of-function mutation of GPAM has been shown to lead to hypomyelination of corticospinal tract in cerebral palsy patient. To model this rare disease with human brain organoid, we generated a GPAM knockout human embryonic stem cell line SYSUe-008-A by CRISPR/cas9. The GPAM knockout cell line maintains a normal karyotype and shows comparable level of pluripotent stem cell marker expression and differentiation potential as wild-type human embryonic stem cells.


Asunto(s)
Células Madre Embrionarias Humanas , Sistemas CRISPR-Cas/genética , Línea Celular , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Células Madre Embrionarias , Humanos
20.
Mitochondrial DNA B Resour ; 6(7): 1826-1828, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34124357

RESUMEN

Alternanthera philoxeroides (Mart.) Griseb. (Alternanthera philoxeroides) is an important herbage species, which could provide high-quality feed for livestock and poultry breeding. This paper is the first to report the A. philoxeroides's chloroplast genomes, which were detected by de novo sequencing. The results showed that the length of A. philoxeroides' chloroplast genome sequence was 152,255 bp, including a large single-copy (LSC) region (84,670 bp), a small single-copy (SSC) region (17,343 bp), and two inverted repeat (IR) regions (25,121 bp). Alternanthera philoxeroides' chloroplast genome encoded 132 genes including 8 rRNA, 38 tRNA, and 86 protein-coding genes. After phylogenetic and cluster analysis, A. philoxeroides was closest to Amaranthaceae, and the relationship between Amaranthus and Achyranthes was closest.

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