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Reproductive phasiRNAs (phased, small interfering RNAs) are broadly present in angiosperms and play crucial roles in sustaining male fertility. While the premeiotic 21-nt (nucleotides) phasiRNAs and meiotic 24-nt phasiRNA pathways have been extensively studied in maize (Zea mays) and rice (Oryza sativa), a third putative category of reproductive phasiRNAs-named premeiotic 24-nt phasiRNAs-have recently been reported in barley (Hordeum vulgare) and wheat (Triticum aestivum). To determine whether premeiotic 24-nt phasiRNAs are also present in maize and related species and begin to characterize their biogenesis and function, we performed a comparative transcriptome and degradome analysis of premeiotic and meiotic anthers from five maize inbred lines and three teosinte species/subspecies. Our data indicate that a substantial subset of the 24-nt phasiRNA loci in maize and teosinte are already highly expressed at the premeiotic phase. The premeiotic 24-nt phasiRNAs are similar to meiotic 24-nt phasiRNAs in genomic origin and dependence on DCL5 (Dicer-like 5) for biogenesis, however, premeiotic 24-nt phasiRNAs are unique in that they are likely i) not triggered by microRNAs, ii) not loaded by AGO18 proteins, and iii) not capable of mediating PHAS precursor cleavage. In addition, we also observed a group of premeiotic 24-nt phasiRNAs in rice using previously published data. Together, our results indicate that the premeiotic 24-nt phasiRNAs constitute a unique class of reproductive phasiRNAs and are present more broadly in the grass family (Poaceae) than previously known.
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Meiose , RNA de Plantas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Meiose/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transcriptoma , Oryza/genética , Oryza/metabolismoRESUMO
Impairments in social relationships and awareness are features observed in autism spectrum disorders (ASDs). However, the underlying mechanisms remain poorly understood. Shank2 is a high-confidence ASD candidate gene and localizes primarily to postsynaptic densities (PSDs) of excitatory synapses in the central nervous system (CNS). We show here that loss of Shank2 in mice leads to a lack of social attachment and bonding behavior towards pubs independent of hormonal, cognitive, or sensitive deficits. Shank2-/- mice display functional changes in nuclei of the social attachment circuit that were most prominent in the medial preoptic area (MPOA) of the hypothalamus. Selective enhancement of MPOA activity by DREADD technology re-established social bonding behavior in Shank2-/- mice, providing evidence that the identified circuit might be crucial for explaining how social deficits in ASD can arise.
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Transtorno Autístico/tratamento farmacológico , Modelos Animais de Doenças , Relações Interpessoais , Comportamento Materno/efeitos dos fármacos , Proteínas do Tecido Nervoso/fisiologia , Piperazinas/farmacologia , Área Pré-Óptica/efeitos dos fármacos , Animais , Transtorno Autístico/etiologia , Transtorno Autístico/metabolismo , Transtorno Autístico/patologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Área Pré-Óptica/metabolismo , Área Pré-Óptica/patologia , SinapsesRESUMO
The Shank3 gene encodes the major postsynaptic scaffolding protein SHANK3. Its mutation causes a syndromic form of autism spectrum disorder (ASD): Phelan-McDermid Syndrome (PMDS). It is characterized by global developmental delay, intellectual disorders (ID), ASD behavior, affective symptoms, as well as extra-cerebral symptoms. Although Shank3 deficiency causes a variety of molecular alterations, they do not suffice to explain all clinical aspects of this heterogenic syndrome. Since global gene expression alterations in Shank3 deficiency remain inadequately studied, we explored the transcriptome in vitro in primary hippocampal cells from Shank3∆11(-/-) mice, under control and lithium (Li) treatment conditions, and confirmed the findings in vivo. The Shank3∆11(-/-) genotype affected the overall transcriptome. Remarkably, extracellular matrix (ECM) and cell cycle transcriptional programs were disrupted. Accordingly, in the hippocampi of adolescent Shank3∆11(-/-) mice we found proteins of the collagen family and core cell cycle proteins downregulated. In vitro Li treatment of Shank3∆11(-/-) cells had a rescue-like effect on the ECM and cell cycle gene sets. Reversed ECM gene sets were part of a network, regulated by common transcription factors (TF) such as cAMP responsive element binding protein 1 (CREB1) and ß-Catenin (CTNNB1), which are known downstream effectors of synaptic activity and targets of Li. These TFs were less abundant and/or hypo-phosphorylated in hippocampi of Shank3∆11(-/-) mice and could be rescued with Li in vitro and in vivo. Our investigations suggest the ECM compartment and cell cycle genes as new players in the pathophysiology of Shank3 deficiency, and imply involvement of transcriptional regulators, which can be modulated by Li. This work supports Li as potential drug in the management of PMDS symptoms, where a Phase III study is ongoing.
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Matriz Extracelular , Hipocampo , Camundongos Knockout , Proteínas do Tecido Nervoso , beta Catenina , Animais , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Hipocampo/metabolismo , Matriz Extracelular/metabolismo , Camundongos , beta Catenina/metabolismo , beta Catenina/genética , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/metabolismo , Deleção Cromossômica , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Cromossomos Humanos Par 22/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Masculino , Transcriptoma/genética , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/tratamento farmacológico , Camundongos Endogâmicos C57BL , Lítio/farmacologia , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Células CultivadasRESUMO
Synaptic dysfunction is a key feature of SHANK-associated disorders such as autism spectrum disorder, schizophrenia, and Phelan-McDermid syndrome. Since detailed knowledge of their effect on synaptic nanostructure remains limited, we aimed to investigate such alterations in ex11|SH3 SHANK3-KO mice combining expansion and STED microscopy. This enabled high-resolution imaging of mosaic-like arrangements formed by synaptic proteins in both human and murine brain tissue. We found distinct shape-profiles as fingerprints of the murine postsynaptic scaffold across brain regions and genotypes, as well as alterations in the spatial and molecular organization of subsynaptic domains under SHANK3-deficient conditions. These results provide insights into synaptic nanostructure in situ and advance our understanding of molecular mechanisms underlying synaptic dysfunction in neuropsychiatric disorders.
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BACKGROUND: Insight into the pathophysiology of inflammatory skin diseases, especially at the proteomic level, is severely hampered by the lack of adequate in situ data. OBJECTIVE: Characterize lesional and nonlesional skin of inflammatory skin diseases using skin microdialysis. METHODS: Skin microdialysis samples from patients with atopic dermatitis (AD, n=6), psoriasis vulgaris (PSO, n=7) or prurigo nodularis (PN, n=6), as well as healthy controls (n=7) were subjected to proteomics and multiplex cytokine analysis. Single-cell RNA sequencing of skin biopsy specimens was used to identify the cellular origin of cytokines. RESULTS: Among the top 20 enriched GO annotations, NAD metabolic process, regulation of secretion by cell, and pyruvate metabolic process were elevated in microdialysates from lesional AD skin compared with both nonlesional skin and controls. The top 20 enriched KEGG pathways in these three groups overlapped almost completely. In contrast, nonlesional skin from patients with PSO or PN and control skin showed no overlap with lesional skin in this KEGG pathway analysis. Lesional skin from patients with PSO, but not AD or PN, showed significantly elevated protein levels of MCP-1 compared to nonlesional skin. IL-8 was elevated in lesional vs nonlesional AD and PSO skin, whereas IL-12p40 and IL-22 were higher only in lesional PSO skin. Integrated single-cell RNA-seq data revealed identical cellular sources of these cytokines in AD, PSO and PN. CONCLUSION: Based on microdialysate, proteomic data of lesional PSO and PN skin, but not lesional AD skin, differed significantly from those of nonlesional skin. IL-8, IL-22, MCP-1 and IL-12p40 might be suitable markers for minimally invasive molecular profiling.
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Anastasis is a phenomenon observed in cancer cells, where cells that have initiated apoptosis are able to recover and survive. This molecular event is increasingly recognized as a potential contributor to cancer metastasis, facilitating the survival and migration of tumor cells. Nevertheless, the identification of a specific surface marker for detecting cancer cells in anastasis remained elusive. Here we report our observation that the cell surface expression of CD24 is preferentially enriched in a non-adherent FSClowSSChigh melanoma subpopulation, which is generally considered a non-viable population in cultivated melanoma cell lines. More than 90% of non-adherent FSClowSSChighCD24+ve metastatic melanoma cells exhibited bonafide features of apoptosis on the cell surface and in the nucleus, marking apoptotic or seemingly apoptotic subpopulations of the in vitro cultivated metastatic melanoma cell lines. Unexpectedly, however, the CD24+ve subpopulation, despite being apoptotic, showed evidence of metabolic activity and exhibited proliferative capacities, including anchorage-independent growth, when inoculated in soft agarose growth medium. These findings indicate that apoptotic FSClowSSChighCD24+ve melanoma subpopulations are capable of reversing the progression of apoptosis. We report CD24 as the first novel cell surface marker for anastasis in melanoma cells.
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Soon after fertilization of egg and sperm, plant genomes become transcriptionally activated and drive a series of coordinated cell divisions to form the basic body plan during embryogenesis. Early embryonic cells rapidly diversify from each other, and investigation of the corresponding gene expression dynamics can help elucidate underlying cellular differentiation programs. However, current plant embryonic transcriptome datasets either lack cell-specific information or have RNA contamination from surrounding non-embryonic tissues. We have coupled fluorescence-activated nuclei sorting together with single-nucleus mRNA-sequencing to construct a gene expression atlas of Arabidopsis thaliana early embryos at single-cell resolution. In addition to characterizing cell-specific transcriptomes, we found evidence that distinct epigenetic and transcriptional regulatory mechanisms operate across emerging embryonic cell types. These datasets and analyses, as well as the approach we devised, are expected to facilitate the discovery of molecular mechanisms underlying pattern formation in plant embryos. This article has an associated 'The people behind the papers' interview.
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Arabidopsis/embriologia , Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Transcriptoma , Núcleo Celular/metabolismo , Desenvolvimento Embrionário , Epigenômica , Perfilação da Expressão Gênica , Genoma de Planta , Células Vegetais/metabolismo , RNA Mensageiro , Fatores de TranscriçãoRESUMO
Co-evolution between hosts' and parasites' genomes shapes diverse pathways of acquired immunity based on silencing small (s)RNAs. In plants, sRNAs cause heterochromatinization, sequence degeneration, and, ultimately, loss of autonomy of most transposable elements (TEs). Recognition of newly invasive plant TEs, by contrast, involves an innate antiviral-like silencing response. To investigate this response's activation, we studied the single-copy element EVADÉ (EVD), one of few representatives of the large Ty1/Copia family able to proliferate in Arabidopsis when epigenetically reactivated. In Ty1/Copia elements, a short subgenomic mRNA (shGAG) provides the necessary excess of structural GAG protein over the catalytic components encoded by the full-length genomic flGAG-POL. We show here that the predominant cytosolic distribution of shGAG strongly favors its translation over mostly nuclear flGAG-POL. During this process, an unusually intense ribosomal stalling event coincides with mRNA breakage yielding unconventional 5'OH RNA fragments that evade RNA quality control. The starting point of sRNA production by RNA-DEPENDENT-RNA-POLYMERASE-6 (RDR6), exclusively on shGAG, occurs precisely at this breakage point. This hitherto-unrecognized "translation-dependent silencing" (TdS) is independent of codon usage or GC content and is not observed on TE remnants populating the Arabidopsis genome, consistent with their poor association, if any, with polysomes. We propose that TdS forms a primal defense against EVD de novo invasions that underlies its associated sRNA pattern.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Elementos de DNA Transponíveis/genética , Regulação da Expressão Gênica de Plantas , RNA Interferente Pequeno/genéticaRESUMO
Melanoma is the deadliest of skin cancers and has a high tendency to metastasize to distant organs. Calcium and metabolic signals contribute to melanoma invasiveness; however, the underlying molecular details are elusive. The MCU complex is a major route for calcium into the mitochondrial matrix but whether MCU affects melanoma pathobiology was not understood. Here, we show that MCUA expression correlates with melanoma patient survival and is decreased in BRAF kinase inhibitor-resistant melanomas. Knockdown (KD) of MCUA suppresses melanoma cell growth and stimulates migration and invasion. In melanoma xenografts, MCUA_KD reduces tumor volumes but promotes lung metastases. Proteomic analyses and protein microarrays identify pathways that link MCUA and melanoma cell phenotype and suggest a major role for redox regulation. Antioxidants enhance melanoma cell migration, while prooxidants diminish the MCUA_KD -induced invasive phenotype. Furthermore, MCUA_KD increases melanoma cell resistance to immunotherapies and ferroptosis. Collectively, we demonstrate that MCUA controls melanoma aggressive behavior and therapeutic sensitivity. Manipulations of mitochondrial calcium and redox homeostasis, in combination with current therapies, should be considered in treating advanced melanoma.
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Cálcio , Melanoma , Humanos , Cálcio/metabolismo , Proteômica , Melanoma/genética , Melanoma/metabolismo , Oxirredução , Fenótipo , Linhagem Celular TumoralRESUMO
Histopathological assessment of tissue samples after prolonged formalin fixation has been described previously, but currently there is only limited knowledge regarding the feasibility of molecular pathology on such tissue. In this pilot study, we tested routine molecular pathology methods (DNA isolation, DNA pyrosequencing/next-generation sequencing, DNA methylation analysis, RT-PCR, clonality analysis and fluorescence in situ hybridization) on tissue samples from 11 tumor entities as well as non-neoplastic brain tissue from 43 body donors during the gross anatomy course at Ulm University (winter semester 2019/20 and 2020/21). The mean post mortem interval until fixation was 2.5 ± 1.6 days (range, 1-6 days). Fixation was performed with aqueous formaldehyde solution (formalin, 1.5-2%). The mean storage time of body donors was 12.8 ± 5.6 months (range, 7-25 months). While most diagnostic methods were successful, samples showed significant variability in DNA quality and evaluability. DNA pyrosequencing as well as next-generation sequencing was successful in all investigated samples. Methylation analyses were partially not successful in some extend due to limited intact DNA yield for these analyses. Taken together, the use of prolonged formalin-fixed tissue samples from body donors offers new avenues in research and education, as these samples could be used for morpho-molecular studies and the establishment of biobanks, especially for tissue types that cannot be preserved and studied in vivo. Pathological ward rounds, sample collection, and histopathological and molecular workup have been integrated in the gross anatomy course in Ulm as an integral part of the curriculum, linking anatomy and pathology and providing medical students early insight into the broad field of (molecular) pathology.
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Metilação de DNA , Formaldeído , Sequenciamento de Nucleotídeos em Larga Escala , Patologia Molecular , Doadores de Tecidos , Fixação de Tecidos , Humanos , Fixação de Tecidos/métodos , Patologia Molecular/métodos , Metilação de DNA/genética , Projetos Piloto , Hibridização in Situ Fluorescente/métodos , Feminino , Neoplasias/genética , Neoplasias/patologiaRESUMO
BACKGROUND: The subcellular distribution of CD30 on mast cells and the presence of eosinophils in cutaneous mastocytosis require further investigation, especially as the cell surface expression of CD30 is critical for the therapeutic response of systemic mastocytosis to brentuximab vedotin. OBJECTIVE: Investigation of 147 biopsy specimens from 143 patients with cutaneous mastocytosis for mast cell density and distribution, frequency of CD30 expression, CD30 staining patterns, and presence and distribution of eosinophils. Correlation with clinical patterns. METHODS: Retrospective multicenter immunohistochemical study of CD30 expression, eosinophils and basic clinical data in cutaneous mastocytosis. RESULTS: CD30 expression was found in all samples (cut-off: ≥1%), whereby the staining was predominantly cytoplasmic in 99% of the samples. Additional membrane staining was detected in 62% of the samples. Surface expression of CD30 was more common in biopsy specimens with a high mast cell burden and in biopsy specimens with a higher CD30 expression rate. Eosinophils were admixed in 58% of the samples. Females and older patients showed a trend of a lower mast cell burden. LIMITATIONS: Retrospective study on formalin-fixed and paraffin-embedded tissue without functional analysis. CONCLUSION: Most cases of cutaneous mastocytosis show cell surface expression of CD30 expression and is, therefore, in principle, accessible for therapy with antibodies against CD30, provided the overall situation of the patient warrants.
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ABSTRACT: Histologic differentiation between melanoma in situ in chronically sun-damaged skin (CSDS) [lentigo maligna (LM)] and CSDS without malignancy is difficult because signs of melanocyte activation and proliferation are found in both. A potentially reliable and quantifiable criterion is melanocyte density (MD). Here, we evaluated whether and to what extent MD allows the distinction between LM and CSDS, which is particularly relevant for the evaluation of borderline cases and surgical margins.Articles assessing MD in LM and/or CSDS were evaluated in a systematic review. The results were categorized and compared according to staining. Cutoff values were included whenever stated.Twenty articles matched the selection criteria. Six hundred forty-four samples of CSDS and 227 samples of LM were considered. In each individual study, mean MD scores were higher for LM than for CSDS. However, looking at the overall study situation, it becomes clear that the data are very heterogeneous and show overlaps. Therefore, no reliable orientation value can be derived. Only 1 article defined a cutoff value.The data of MD in LM in contrast to CSDS were sparse, and a defined cutoff value was only mentioned in 1 article for microphthalmia-associated transcription factor, which cannot yet be generalized. Especially regarding the importance for the definition of surgical resection margins, this unsatisfactory data set highlights the need for further studies. More precise diagnostic criteria could spare some patients extensive and possibly disfiguring surgery.
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Melanócitos , Melanoma , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/diagnóstico , Melanócitos/patologia , Melanoma/patologia , Melanoma/diagnóstico , Contagem de Células , Sarda Melanótica de Hutchinson/patologia , Sarda Melanótica de Hutchinson/diagnóstico , Luz Solar/efeitos adversos , Diagnóstico DiferencialRESUMO
Quantitative variation in expression of the Arabidopsis floral repressor FLC influences whether plants overwinter before flowering, or have a rapid cycling habit enabling multiple generations a year. Genetic analysis has identified activators and repressors of FLC expression but how they interact to set expression level is poorly understood. Here, we show that antagonistic functions of the FLC activator FRIGIDA (FRI) and the repressor FCA, at a specific stage of embryo development, determine FLC expression and flowering. FRI antagonizes an FCA-induced proximal polyadenylation to increase FLC expression and delay flowering. Sector analysis shows that FRI activity during the early heart stage of embryo development maximally delays flowering. Opposing functions of cotranscriptional regulators during an early embryonic developmental window thus set FLC expression levels and determine flowering time.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/metabolismo , Proteínas de Ligação a RNA/metabolismo , Arabidopsis/embriologia , Arabidopsis/crescimento & desenvolvimento , Desenvolvimento Embrionário , Flores/crescimento & desenvolvimento , PoliadenilaçãoRESUMO
BACKGROUND: SHANKs are major scaffolding proteins at postsynaptic densities (PSDs) in the central nervous system. Mutations in all three family members have been associated with neurodevelopmental disorders such as autism spectrum disorders (ASDs). Despite the pathophysiological importance of SHANK2 and SHANK3 mutations in humans, research on the expression of these proteins is mostly based on rodent model organisms. RESULTS: In the present study, cellular and neuropil SHANK2 expression was analyzed by immunofluorescence (IF) staining of post mortem human brain tissue from four male individuals (19 brain regions). Mouse brains were analyzed in comparison to evaluate the degree of phylogenetic conservation. Furthermore, SHANK2 and SHANK3 isoform patterns were compared in human and mouse brain lysates. While isoform expression and subcellular distribution were largely conserved, differences in neuropil levels of SHANK2 were found by IF staining: Maximum expression was concordantly measured in the cerebellum; however, higher SHANK2 expression was detected in the human brainstem and thalamus when compared to mice. One of the lowest SHANK2 levels was found in the human amygdala, a moderately expressing region in mouse. Quantification of SHANK3 IF in mouse brains unveiled a distribution comparable to humans. CONCLUSIONS: In summary, these data show that the overall expression pattern of SHANK is largely conserved in defined brain regions; however, differences do exist, which need to be considered in the translation of rodent studies. The summarized expression patterns of SHANK2 and SHANK3 should serve as a reference for future studies.
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Transtorno Autístico , Proteínas do Tecido Nervoso , Animais , Humanos , Masculino , Camundongos , Transtorno Autístico/genética , Encéfalo/metabolismo , Hipocampo/metabolismo , Filogenia , Isoformas de Proteínas/metabolismo , Proteínas do Tecido Nervoso/genéticaRESUMO
BACKGROUND: Post mortem human brain tissue is an essential resource to study cell types, connectivity as well as subcellular structures down to the molecular setup of the central nervous system especially with respect to the plethora of brain diseases. A key method is immunostaining with fluorescent dyes, which allows high-resolution imaging in three dimensions of multiple structures simultaneously. Although there are large collections of formalin-fixed brains, research is often limited because several conditions arise that complicate the use of human brain tissue for high-resolution fluorescence microscopy. RESULTS: In this study, we developed a clearing approach for immunofluorescence-based analysis of perfusion- and immersion-fixed post mortem human brain tissue, termed human Clear Lipid-exchanged Acrylamide-hybridized Rigid Imaging / Immunostaining / In situ hybridization-compatible Tissue-hYdrogel (hCLARITY). hCLARITY is optimized for specificity by reducing off-target labeling and yields very sensitive stainings in human brain sections allowing for super-resolution microscopy with unprecedented imaging of pre- and postsynaptic compartments. Moreover, hallmarks of Alzheimer's disease were preserved with hCLARITY, and importantly classical 3,3'-diaminobenzidine (DAB) or Nissl stainings are compatible with this protocol. hCLARITY is very versatile as demonstrated by the use of more than 30 well performing antibodies and allows for de- and subsequent re-staining of the same tissue section, which is important for multi-labeling approaches, e.g., in super-resolution microscopy. CONCLUSIONS: Taken together, hCLARITY enables research of the human brain with high sensitivity and down to sub-diffraction resolution. It therefore has enormous potential for the investigation of local morphological changes, e.g., in neurodegenerative diseases.
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Encéfalo , Sistema Nervoso Central , Humanos , Microscopia de Fluorescência , Acrilamida , Corantes FluorescentesRESUMO
Immunotherapies using checkpoint blockade and BRAF/MEK therapies have improved overall survival (OS) in patients with unresectable melanoma metastases. In this retrospective study, we aimed to demonstrate the resulting increase in melanoma-specific survival (MSS) and OS after the excision of primary melanomas (≥1 mm thick) and sentinel lymph node (SN) biopsy (SNB). Using Kaplan-Meier estimates and Cox models, we compared two consecutive cohorts. Patients in cohort 1 (N = 518) underwent SNB between 1998 and 2009, and patients in cohort 2 (N = 460) between 2010 and 2017, when checkpoint blockade and BRAF/(MEK) inhibition became available for the treatment of unresectable relapses. The median follow-up times were 120 and 73 months, respectively. While recurrence-free and distant metastasis-free survival rates remained very similar, MSS and OS increased in favor of cohort 2. The estimated 5-year OS rate of SN-positive patients increased by 14.3% (78.5% vs 64.2%, logrank test: P = .005). The MSS benefit was significant even with low SN tumor burden (metastasis diameter < 1 mm). On multivariate analyses, the risk-reduction in favor of cohort 2 was significant in the total population and in the SN-negative and SN-positive subgroups. In SN-positive patients, besides the availability of modern therapies, SN metastasis diameter and ulceration were independent factors of MSS and OS. Treatment of unresectable melanoma recurrences with modern drug therapies results in significantly higher survival rates in a population with SNB. The survival benefit measured from primary melanoma affects both the SN-positive and SN-negative subpopulations.
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Melanoma , Neoplasias Cutâneas , Humanos , Estudos Retrospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/cirurgia , Biópsia de Linfonodo Sentinela/métodos , Melanoma/patologia , Excisão de Linfonodo , Atenção Primária à Saúde , Quinases de Proteína Quinase Ativadas por Mitógeno , PrognósticoRESUMO
Reactive oxygen species (ROS) are emerging as important regulators of cancer growth and metastatic spread. However, how cells integrate redox signals to affect cancer progression is not fully understood. Mitochondria are cellular redox hubs, which are highly regulated by interactions with neighboring organelles. Here, we investigated how ROS at the endoplasmic reticulum (ER)-mitochondria interface are generated and translated to affect melanoma outcome. We show that TMX1 and TMX3 oxidoreductases, which promote ER-mitochondria communication, are upregulated in melanoma cells and patient samples. TMX knockdown altered mitochondrial organization, enhanced bioenergetics, and elevated mitochondrial- and NOX4-derived ROS. The TMX-knockdown-induced oxidative stress suppressed melanoma proliferation, migration, and xenograft tumor growth by inhibiting NFAT1. Furthermore, we identified NFAT1-positive and NFAT1-negative melanoma subgroups, wherein NFAT1 expression correlates with melanoma stage and metastatic potential. Integrative bioinformatics revealed that genes coding for mitochondrial- and redox-related proteins are under NFAT1 control and indicated that TMX1, TMX3, and NFAT1 are associated with poor disease outcome. Our study unravels a novel redox-controlled ER-mitochondria-NFAT1 signaling loop that regulates melanoma pathobiology and provides biomarkers indicative of aggressive disease.
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Melanoma/patologia , Proteínas de Membrana/metabolismo , Fatores de Transcrição NFATC/metabolismo , Oxirredução , Isomerases de Dissulfetos de Proteínas/metabolismo , Tiorredoxinas/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Progressão da Doença , Retículo Endoplasmático/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Melanoma/metabolismo , Proteínas de Membrana/genética , Camundongos , Mitocôndrias/metabolismo , NADPH Oxidase 4/metabolismo , Transplante de Neoplasias , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Análise de Sobrevida , Tiorredoxinas/genética , Regulação para CimaRESUMO
BACKGROUND: Nitrogen-fixing nodules occur in ten related taxonomic lineages interspersed with lineages of non-nodulating plant species. Nodules result from an endosymbiosis between plants and diazotrophic bacteria; rhizobia in the case of legumes and Parasponia and Frankia in the case of actinorhizal species. Nodulating plants share a conserved set of symbiosis genes, whereas related non-nodulating sister species show pseudogenization of several key nodulation-specific genes. Signalling and cellular mechanisms critical for nodulation have been co-opted from the more ancient plant-fungal arbuscular endomycorrhizal symbiosis. Studies in legumes and actinorhizal plants uncovered a key component in symbiotic signalling, the LRR-type SYMBIOSIS RECEPTOR KINASE (SYMRK). SYMRK is essential for nodulation and arbuscular endomycorrhizal symbiosis. To our surprise, however, despite its arbuscular endomycorrhizal symbiosis capacities, we observed a seemingly critical mutation in a donor splice site in the SYMRK gene of Trema orientalis, the non-nodulating sister species of Parasponia. This led us to investigate the symbiotic functioning of SYMRK in the Trema-Parasponia lineage and to address the question of to what extent a single nucleotide polymorphism in a donor splice site affects the symbiotic functioning of SYMRK. RESULTS: We show that SYMRK is essential for nodulation and endomycorrhization in Parasponia andersonii. Subsequently, it is revealed that the 5'-intron donor splice site of SYMRK intron 12 is variable and, in most dicotyledon species, doesn't contain the canonical dinucleotide 'GT' signature but the much less common motif 'GC'. Strikingly, in T. orientalis, this motif is converted into a rare non-canonical 5'-intron donor splice site 'GA'. This SYMRK allele, however, is fully functional and spreads in the T. orientalis population of Malaysian Borneo. A further investigation into the occurrence of the non-canonical GA-AG splice sites confirmed that these are extremely rare. CONCLUSION: SYMRK functioning is highly conserved in legumes, actinorhizal plants, and Parasponia. The gene possesses a non-common 5'-intron GC donor splice site in intron 12, which is converted into a GA in T. orientalis accessions of Malaysian Borneo. The discovery of this functional GA-AG splice site in SYMRK highlights a gap in our understanding of splice donor sites.
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Fabaceae , Rhizobium , Trema , Simbiose/genética , Trema/metabolismo , Rhizobium/fisiologia , Nodulação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fosfotransferases , Fabaceae/metabolismo , Plantas/metabolismo , Fixação de Nitrogênio/genéticaRESUMO
Despite recent advances in prophylactic vaccination, SARS-CoV-2 infections continue to cause significant morbidity. A better understanding of immune response differences between vaccinated individuals with and without later SARS-CoV-2 breakthrough infection is urgently needed. CoV-ADAPT is a prospective long-term study comparing humoral (anti-spike-RBD-IgG, neutralization capacity, avidity) and cellular (spike-induced T-cell interferon-γ [IFN-γ] release) immune responses in individuals vaccinated against SARS-CoV-2 at four different time points (three before and one after third vaccination). In this cohort study, 62 fully vaccinated individuals presented with SARS-CoV-2 breakthrough infections vs 151 without infection 3-7 months following third vaccination. Breakthrough infections significantly increased anti-spike-RBD-IgG (p < 0.01), but not spike-directed T-cell IFN-γ release (TC) or antibody avidity. Despite comparable surrogate neutralization indices, the functional neutralization capacity against SARS-CoV-2-assessed via a tissue culture-based assay-was significantly higher following breakthrough vs no breakthrough infection. Anti-spike-RBD-IgG and antibody avidity decreased with age (p < 0.01) and females showed higher anti-spike-RBD-IgG (p < 0.01), and a tendency towards higher antibody avidity (p = 0.051). The association between humoral and cellular immune responses previously reported at various time points was lost in subjects after breakthrough infections (p = 0.807). Finally, a machine-learning approach based on our large immunological dataset (a total of 49 variables) from different time points was unable to predict breakthrough infections (area under the curve: 0.55). In conclusion, distinct differences in humoral vs cellular immune responses in fully vaccinated individuals with or without breakthrough infection could be demonstrated. Breakthrough infections predominantly drive the humoral response without boosting the cellular component. Breakthrough infections could not be predicted based on immunological data, which indicates a superior role of environmental factors (e.g., virus exposure) in individualized risk assessment.
Assuntos
COVID-19 , Feminino , Humanos , SARS-CoV-2 , Infecções Irruptivas , Estudos de Coortes , Estudos Prospectivos , Interferon gama , Imunidade Celular , Imunoglobulina G , Anticorpos Antivirais , Vacinação , Imunidade HumoralRESUMO
Mutations or deletions of the SHANK3 gene are causative for Phelan-McDermid syndrome (PMDS), a syndromic form of autism spectrum disorders (ASDs). We analyzed Shank3Δ11(-/-) mice and organoids from PMDS individuals to study effects on myelin. SHANK3 was found to be expressed in oligodendrocytes and Schwann cells, and MRI analysis of Shank3Δ11(-/-) mice revealed a reduced volume of the corpus callosum as seen in PMDS patients. Myelin proteins including myelin basic protein showed significant temporal and regional differences with lower levels in the CNS but increased amounts in the PNS of Shank3Δ11(-/-) animals. Node, as well as paranode, lengths were increased and ultrastructural analysis revealed region-specific alterations of the myelin sheaths. In PMDS hiPSC-derived cerebral organoids we observed an altered number and delayed maturation of myelinating cells. These findings provide evidence that, in addition to a synaptic deregulation, impairment of myelin might profoundly contribute to the clinical manifestation of SHANK3 deficiency.