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1.
Mol Cell ; 80(1): 156-163.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007255

RESUMO

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift toward distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that, in Drosophila, the highly conserved protein ELAV globally regulates all sites of neuronal 3' end processing and directly binds to proximal polyadenylation sites of target mRNAs in vivo. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in an ELAV loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralog FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue ELAV-mediated alternative polyadenylation and alternative splicing. We propose that exon-activated functional rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Éxons/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Masculino , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
2.
Mol Cell ; 80(1): 140-155.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007254

RESUMO

The tissue-specific deployment of highly extended neural 3' UTR isoforms, generated by alternative polyadenylation (APA), is a broad and conserved feature of metazoan genomes. However, the factors and mechanisms that control neural APA isoforms are not well understood. Here, we show that three ELAV/Hu RNA binding proteins (Elav, Rbp9, and Fne) have similar capacities to induce a lengthened 3' UTR landscape in an ectopic setting. These factors promote accumulation of chromatin-associated, 3' UTR-extended, nascent transcripts, through inhibition of proximal polyadenylation site (PAS) usage. Notably, Elav represses an unannotated splice isoform of fne, switching the normally cytoplasmic Fne toward the nucleus in elav mutants. We use genomic profiling to reveal strong and broad loss of neural APA in elav/fne double mutant CNS, the first genetic background to largely abrogate this distinct APA signature. Overall, we demonstrate how regulatory interplay and functionally overlapping activities of neural ELAV/Hu RBPs drives the neural APA landscape.


Assuntos
Regiões 3' não Traduzidas/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Neurônios/metabolismo , Processamento Alternativo/genética , Motivos de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas ELAV/química , Larva/metabolismo , Mutação/genética , Poli A/metabolismo , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Nat Commun ; 11(1): 4956, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009383

RESUMO

Tet-enzyme-mediated 5-hydroxymethylation of cytosines in DNA plays a crucial role in mouse embryonic stem cells (ESCs). In RNA also, 5-hydroxymethylcytosine (5hmC) has recently been evidenced, but its physiological roles are still largely unknown. Here we show the contribution and function of this mark in mouse ESCs and differentiating embryoid bodies. Transcriptome-wide mapping in ESCs reveals hundreds of messenger RNAs marked by 5hmC at sites characterized by a defined unique consensus sequence and particular features. During differentiation a large number of transcripts, including many encoding key pluripotency-related factors (such as Eed and Jarid2), show decreased cytosine hydroxymethylation. Using Tet-knockout ESCs, we find Tet enzymes to be partly responsible for deposition of 5hmC in mRNA. A transcriptome-wide search further reveals mRNA targets to which Tet1 and Tet2 bind, at sites showing a topology similar to that of 5hmC sites. Tet-mediated RNA hydroxymethylation is found to reduce the stability of crucial pluripotency-promoting transcripts. We propose that RNA cytosine 5-hydroxymethylation by Tets is a mark of transcriptome flexibility, inextricably linked to the balance between pluripotency and lineage commitment.


Assuntos
5-Metilcitosina/análogos & derivados , Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA/metabolismo , 5-Metilcitosina/metabolismo , Animais , Especificidade de Anticorpos/imunologia , Sequência de Bases , Corpos Embrioides/metabolismo , Camundongos , Modelos Biológicos , Células-Tronco Pluripotentes/metabolismo , Ligação Proteica , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
4.
Cells ; 9(9)2020 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899484

RESUMO

Hybrid nanoparticles from lipidic and polymeric components were assembled to serve as vehicles for the transfection of messenger RNA (mRNA) using different portions of the cationic lipid DOTAP (1,2-Dioleoyl-3-trimethylammonium-propane) and the cationic biopolymer protamine as model systems. Two different sequential assembly approaches in comparison with a direct single-step protocol were applied, and molecular organization in correlation with biological activity of the resulting nanoparticle systems was investigated. Differences in the structure of the nanoparticles were revealed by thorough physicochemical characterization including small angle neutron scattering (SANS), small angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). All hybrid systems, combining lipid and polymer, displayed significantly increased transfection in comparison to lipid/mRNA and polymer/mRNA particles alone. For the hybrid nanoparticles, characteristic differences regarding the internal organization, release characteristics, and activity were determined depending on the assembly route. The systems with the highest transfection efficacy were characterized by a heterogenous internal organization, accompanied by facilitated release. Such a system could be best obtained by the single step protocol, starting with a lipid and polymer mixture for nanoparticle formation.


Assuntos
Biopolímeros/química , Lipídeos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Transfecção/métodos , Animais , Linhagem Celular , Ácidos Graxos Monoinsaturados/química , Feminino , Heparina/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Tamanho da Partícula , Compostos de Amônio Quaternário/química , RNA Mensageiro/química
5.
PLoS Pathog ; 16(8): e1008845, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866210

RESUMO

Modified vaccinia virus Ankara (MVA) is an approved smallpox vaccine and a promising vaccine vector for other pathogens as well as for cancer therapeutics with more than 200 current or completed clinical trials. MVA was derived by passaging the parental Ankara vaccine virus hundreds of times in chick embryo fibroblasts during which it lost the ability to replicate in human and most other mammalian cells. Although this replication deficiency is an important safety feature, the genetic basis of the host restriction is not understood. Here, an unbiased human genome-wide RNAi screen in human A549 cells revealed that the zinc-finger antiviral protein (ZAP), previously shown to inhibit certain RNA viruses, is a host restriction factor for MVA, a DNA virus. Additional studies demonstrated enhanced MVA replication in several human cell lines following knockdown of ZAP. Furthermore, CRISPR-Cas9 knockout of ZAP in human A549 cells increased MVA replication and spread by more than one log but had no effect on a non-attenuated strain of vaccinia virus. The intact viral C16 protein, which had been disrupted in MVA, antagonized ZAP by binding and sequestering the protein in cytoplasmic punctate structures. Studies aimed at exploring the mechanism by which ZAP restricts MVA replication in the absence of C16 showed that knockout of ZAP had no discernible effect on viral DNA or individual mRNA or protein species as determined by droplet digital polymerase chain reaction, deep RNA sequencing and mass spectrometry, respectively. Instead, inactivation of ZAP reduced the number of aberrant, dense, spherical particles that typically form in MVA-infected human cells, suggesting that ZAP has a novel role in interfering with a late step in the assembly of infectious MVA virions in the absence of the C16 protein.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Vírus Vaccinia/fisiologia , Replicação Viral/fisiologia , Células A549 , Animais , Galinhas , Citoplasma/metabolismo , Citoplasma/virologia , DNA Viral/genética , DNA Viral/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , RNA-Seq , Proteínas Repressoras/genética
6.
Anim Sci J ; 91(1): e13456, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32926548

RESUMO

In this study, we investigated whether bovine oviducts and endometria produce anti-Müllerian hormone (AMH) (for paracrine and autocrine signaling). Reverse transcription-polymerase chain reaction and western blotting detected AMH expression in oviductal and endometrial specimens. Immunohistochemistry revealed robust AMH expression in the ampulla and isthmus epithelia, and the glandular and luminal endometrial epithelia (caruncular endometria). AMH mRNA (measured by real-time PCR) and protein expression in these layers did not significantly differ among estrous phases in adult Japanese Black (JB) heifers (p > .1). Furthermore, the expression in these layers also did not differ among Holstein cows (93.8 ± 5.8 months old), JB heifers (25.5 ± 0.4 months old), and JB cows (97.9 ± 7.9 months old). We also compared AMH concentrations in the oviduct and uterine horn fluids among the three groups (measured by immunoassays). Interestingly, the AMH concentration in the oviduct fluid, but not in the uterine horn fluid, of Holstein cows was lower than those in JB heifers and cows (p < .05). Therefore, bovine oviducts and endometria express AMH and likely secrete it into the oviduct and uterine fluids.


Assuntos
Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Endométrio/metabolismo , Células Epiteliais/metabolismo , Expressão Gênica , Oviductos/metabolismo , Animais , Bovinos , Endométrio/citologia , Ciclo Estral/metabolismo , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Útero/metabolismo
7.
Nat Commun ; 11(1): 4607, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929081

RESUMO

Drug tolerance is the basis for acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) including osimertinib, through mechanisms that still remain unclear. Here, we show that while AXL-low expressing EGFR mutated lung cancer (EGFRmut-LC) cells are more sensitive to osimertinib than AXL-high expressing EGFRmut-LC cells, a small population emerge osimertinib tolerance. The tolerance is mediated by the increased expression and phosphorylation of insulin-like growth factor-1 receptor (IGF-1R), caused by the induction of its transcription factor FOXA1. IGF-1R maintains association with EGFR and adaptor proteins, including Gab1 and IRS1, in the presence of osimertinib and restores the survival signal. In AXL-low-expressing EGFRmut-LC cell-derived xenograft and patient-derived xenograft models, transient IGF-1R inhibition combined with continuous osimertinib treatment could eradicate tumors and prevent regrowth even after the cessation of osimertinib. These results indicate that optimal inhibition of tolerant signals combined with osimertinib may dramatically improve the outcome of EGFRmut-LC.


Assuntos
Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Acrilamidas/farmacologia , Idoso de 80 Anos ou mais , Compostos de Anilina/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
BMC Bioinformatics ; 21(1): 396, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894041

RESUMO

BACKGROUND: MicroRNAs are a class of important small noncoding RNAs, which have been reported to be involved in the processes of tumorigenesis and development by targeting a few genes. Existing studies show that the imbalance between cell proliferation and apoptosis is closely related to the initiation and development of cancers. However, the impact of miRNAs on this imbalance has not been studied systematically. RESULTS: In this study, we first construct a cell fate miRNA-gene regulatory network. Then, we propose a systematical method for calculating the global impact of miRNAs on cell fate genes based on the shortest path. Results on breast cancer and liver cancer datasets show that most of the cell fate genes are perturbed by the differentially expressed miRNAs. Most of the top-identified miRNAs are verified in the Human MicroRNA Disease Database (HMDD) and are related to breast and liver cancers. Function analysis shows that the top 20 miRNAs regulate multiple cell fate related function modules and interact tightly based on their functional similarity. Furthermore, more than half of them can promote sensitivity or induce resistance to some anti-cancer drugs. Besides, survival analysis demonstrates that the top-ranked miRNAs are significantly related to the overall survival time in the breast and liver cancers group. CONCLUSION: In sum, this study can help to systematically study the important role of miRNAs on proliferation and apoptosis and thereby uncover the key miRNAs during the process of tumorigenesis. Furthermore, the results of this study will contribute to the development of clinical therapy based miRNAs for cancers.


Assuntos
Apoptose/genética , Proliferação de Células/genética , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Bases de Dados Genéticas , Feminino , Redes Reguladoras de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida
9.
Nature ; 585(7824): 239-244, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879485

RESUMO

Obligate endosymbiosis, in which distantly related species integrate to form a single replicating individual, represents a major evolutionary transition in individuality1-3. Although such transitions are thought to increase biological complexity1,2,4-6, the evolutionary and developmental steps that lead to integration remain poorly understood. Here we show that obligate endosymbiosis between the bacteria Blochmannia and the hyperdiverse ant tribe Camponotini7-11 originated and also elaborated through radical alterations in embryonic development, as compared to other insects. The Hox genes Abdominal A (abdA) and Ultrabithorax (Ubx)-which, in arthropods, normally function to differentiate abdominal and thoracic segments after they form-were rewired to also regulate germline genes early in development. Consequently, the mRNAs and proteins of these Hox genes are expressed maternally and colocalize at a subcellular level with those of germline genes in the germplasm and three novel locations in the freshly laid egg. Blochmannia bacteria then selectively regulate these mRNAs and proteins to make each of these four locations functionally distinct, creating a system of coordinates in the embryo in which each location performs a different function to integrate Blochmannia into the Camponotini. Finally, we show that the capacity to localize mRNAs and proteins to new locations in the embryo evolved before obligate endosymbiosis and was subsequently co-opted by Blochmannia and Camponotini. This pre-existing molecular capacity converged with a pre-existing ecological mutualism12,13 to facilitate both the horizontal transfer10 and developmental integration of Blochmannia into Camponotini. Therefore, the convergence of pre-existing molecular capacities and ecological interactions-as well as the rewiring of highly conserved gene networks-may be a general feature that facilitates the origin and elaboration of major transitions in individuality.


Assuntos
Formigas/embriologia , Formigas/microbiologia , Bactérias , Evolução Biológica , Regulação da Expressão Gênica no Desenvolvimento/genética , Individualidade , Simbiose/genética , Animais , Formigas/citologia , Formigas/genética , Desenvolvimento Embrionário/genética , Feminino , Genes Homeobox/genética , Herança Materna/genética , Oócitos/citologia , Oócitos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Nat Commun ; 11(1): 4873, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978376

RESUMO

Autism spectrum disorder (ASD) is a phenotypically and genetically heterogeneous neurodevelopmental disorder. Despite this heterogeneity, previous studies have shown patterns of molecular convergence in post-mortem brain tissue from autistic subjects. Here, we integrate genome-wide measures of mRNA expression, miRNA expression, DNA methylation, and histone acetylation from ASD and control brains to identify a convergent molecular subtype of ASD with shared dysregulation across both the epigenome and transcriptome. Focusing on this convergent subtype, we substantially expand the repertoire of differentially expressed genes in ASD and identify a component of upregulated immune processes that are associated with hypomethylation. We utilize eQTL and chromosome conformation datasets to link differentially acetylated regions with their cognate genes and identify an enrichment of ASD genetic risk variants in hyperacetylated noncoding regulatory regions linked to neuronal genes. These findings help elucidate how diverse genetic risk factors converge onto specific molecular processes in ASD.


Assuntos
Transtorno do Espectro Autista/genética , Epigenômica/métodos , RNA Mensageiro/metabolismo , Transcriptoma , Encéfalo/metabolismo , Metilação de DNA , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genômica , Histonas/metabolismo , Humanos , MicroRNAs
11.
Nat Commun ; 11(1): 4455, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901005

RESUMO

Dysregulated alternative splicing (AS) driving carcinogenetic mitosis remains poorly understood. Here, we demonstrate that cancer metastasis-associated antigen 1 (MTA1), a well-known oncogenic chromatin modifier, broadly interacts and co-expresses with RBPs across cancers, contributing to cancerous mitosis-related AS. Using developed fCLIP-seq technology, we show that MTA1 binds abundant transcripts, preferentially at splicing-responsible motifs, influencing the abundance and AS pattern of target transcripts. MTA1 regulates the mRNA level and guides the AS of a series of mitosis regulators. MTA1 deletion abrogated the dynamic AS switches of variants for ATRX and MYBL2 at mitotic stage, which are relevant to mitosis-related tumorigenesis. MTA1 dysfunction causes defective mitotic arrest, leads to aberrant chromosome segregation, and results in chromosomal instability (CIN), eventually contributing to tumorigenesis. Currently, little is known about the RNA splicing during mitosis; here, we uncover that MTA1 binds transcripts and orchestrates dynamic splicing of mitosis regulators in tumorigenesis.


Assuntos
Carcinogênese/genética , Carcinogênese/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Mitose/fisiologia , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Processamento Alternativo , Animais , Sítios de Ligação/genética , Montagem e Desmontagem da Cromatina/genética , Instabilidade Cromossômica , Feminino , Células HCT116 , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Mitose/genética , Neoplasias/genética , Neoplasias/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transativadores/antagonistas & inibidores , Transativadores/genética
12.
Nat Commun ; 11(1): 4577, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917881

RESUMO

Nuclear pore complexes (NPCs) are important for cellular functions beyond nucleocytoplasmic trafficking, including genome organization and gene expression. This multi-faceted nature and the slow turnover of NPC components complicates investigations of how individual nucleoporins act in these diverse processes. To address this question, we apply an Auxin-Induced Degron (AID) system to distinguish roles of basket nucleoporins NUP153, NUP50 and TPR. Acute depletion of TPR causes rapid and pronounced changes in transcriptomic profiles. These changes are dissimilar to shifts observed after loss of NUP153 or NUP50, but closely related to changes caused by depletion of mRNA export receptor NXF1 or the GANP subunit of the TRanscription-EXport-2 (TREX-2) mRNA export complex. Moreover, TPR depletion disrupts association of TREX-2 subunits (GANP, PCID2, ENY2) to NPCs and results in abnormal RNA transcription and export. Our findings demonstrate a unique and pivotal role of TPR in gene expression through TREX-2- and/or NXF1-dependent mRNA turnover.


Assuntos
Exodesoxirribonucleases/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Fosfoproteínas/metabolismo , RNA Mensageiro/metabolismo , Linhagem Celular , Regulação da Expressão Gênica , Humanos , Ácidos Indolacéticos/metabolismo , Proteínas Nucleares , Proteínas de Transporte Nucleocitoplasmático , Transporte Proteico , Proteínas de Ligação a RNA , Transcriptoma , Dedos de Zinco
13.
Nat Commun ; 11(1): 4788, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963234

RESUMO

Regenerative proliferation capacity and poor differentiation are histological features usually linked to poor prognosis in head and neck squamous cell carcinoma (hnSCC). However, the pathways that regulate them remain ill-characterized. Here, we show that those traits can be triggered by the RHO GTPase activator VAV2 in keratinocytes present in the skin and oral mucosa. VAV2 is also required to maintain those traits in hnSCC patient-derived cells. This function, which is both catalysis- and RHO GTPase-dependent, is mediated by c-Myc- and YAP/TAZ-dependent transcriptomal programs associated with regenerative proliferation and cell undifferentiation, respectively. High levels of VAV2 transcripts and VAV2-regulated gene signatures are both associated with poor hnSCC patient prognosis. These results unveil a druggable pathway linked to the malignancy of specific SCC subtypes.


Assuntos
Proliferação de Células , Neoplasias de Cabeça e Pescoço/metabolismo , Proteínas Proto-Oncogênicas c-vav/genética , Proteínas Proto-Oncogênicas c-vav/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Animais , Diferenciação Celular , Modelos Animais de Doenças , Epiderme/metabolismo , Epiderme/patologia , GTP Fosfo-Hidrolases , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Hiperplasia/patologia , Queratinócitos/patologia , Camundongos , Camundongos Knockout , Membrana Mucosa/metabolismo , Prognóstico , RNA Mensageiro/metabolismo , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Transcriptoma
14.
Int J Nanomedicine ; 15: 5825-5838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821104

RESUMO

Background and Purpose: The extracellular matrix (ECM) derived from bone marrow mesenchymal stem cells (BMSCs) has been used in regenerative medicine because of its good biological activity; however, its poor mechanical properties limit its application in bone regeneration. The purpose of this study is to construct a three dimensional-printed hydroxyapatite (3D-HA)/BMSC-ECM composite scaffold that not only has biological activity but also sufficient mechanical strength and reasonably distributed spatial structure. Methods: A BMSC-ECM was first extracted and formed into micron-sized particles, and then the ECM particles were modified onto the surface of 3D-HA scaffolds using an innovative linking method to generate composite 3D-HA/BMSC-ECM scaffolds. The 3D-HA scaffolds were used as the control group. The basic properties, biocompatibility and osteogenesis ability of both scaffolds were tested in vitro. Finally, a critical skull defect rat model was created and the osteogenesis effect of the scaffolds was evaluated in vivo. Results: The compressive modulus of the composite scaffolds reached 9.45±0.32 MPa, which was similar to that of the 3D-HA scaffolds (p>0.05). The pore size of the two scaffolds was 305±47 um and 315±34 um (p>0.05), respectively. A CCK-8 assay indicated that the scaffolds did not have cytotoxicity. The composite scaffolds had good cell adhesion ability, with a cell adhesion rate of up to 76.00±6.17% after culturing for 7 hours, while that of the 3D-HA scaffolds was 51.85±4.77% (p<0.01). In addition, the composite scaffold displayed higher alkaline phosphatase (ALP) activity, osteogenesis-related mRNA expression, and calcium nodule formation, thus confirming that the composite scaffolds had good osteogenic activity. The composite scaffolds exhibited good bone repair in vivo and were superior to the 3D-HA scaffolds. Conclusion: We conclude that BMSC-ECM is a good osteogenic material and that the composite scaffolds have good osteogenic ability, which provides a new method and concept for the repair of bone defects.


Assuntos
Durapatita/farmacologia , Matriz Extracelular/metabolismo , Células-Tronco Mesenquimais/citologia , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Hidrodinâmica , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
15.
Nature ; 584(7820): 252-256, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760004

RESUMO

A fundamental challenge in developing treatments for autism spectrum disorders is the heterogeneity of the condition. More than one hundred genetic mutations confer high risk for autism, with each individual mutation accounting for only a small fraction of cases1-3. Subsets of risk genes can be grouped into functionally related pathways, most prominently those involving synaptic proteins, translational regulation, and chromatin modifications. To attempt to minimize this genetic complexity, recent therapeutic strategies have focused on the neuropeptides oxytocin and vasopressin4-6, which regulate aspects of social behaviour in mammals7. However, it is unclear whether genetic risk factors predispose individuals to autism as a result of modifications to oxytocinergic signalling. Here we report that an autism-associated mutation in the synaptic adhesion molecule Nlgn3 results in impaired oxytocin signalling in dopaminergic neurons and in altered behavioural responses to social novelty tests in mice. Notably, loss of Nlgn3 is accompanied by a disruption of translation homeostasis in the ventral tegmental area. Treatment of Nlgn3-knockout mice with a new, highly specific, brain-penetrant inhibitor of MAP kinase-interacting kinases resets the translation of mRNA and restores oxytocin signalling and social novelty responses. Thus, this work identifies a convergence between the genetic autism risk factor Nlgn3, regulation of translation, and oxytocinergic signalling. Focusing on such common core plasticity elements might provide a pragmatic approach to overcoming the heterogeneity of autism. Ultimately, this would enable mechanism-based stratification of patient populations to increase the success of therapeutic interventions.


Assuntos
Transtorno Autístico/metabolismo , Transtorno Autístico/psicologia , Modelos Animais de Doenças , Ocitocina/metabolismo , Comportamento Social , Animais , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Área Tegmentar Ventral/citologia , Área Tegmentar Ventral/efeitos dos fármacos
16.
Nat Commun ; 11(1): 4205, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32826891

RESUMO

Triple negative breast cancer (TNBC) is a deadly form of breast cancer due to the development of resistance to chemotherapy affecting over 30% of patients. New therapeutics and companion biomarkers are urgently needed. Recognizing the elevated expression of glucose transporter 1 (GLUT1, encoded by SLC2A1) and associated metabolic dependencies in TNBC, we investigated the vulnerability of TNBC cell lines and patient-derived samples to GLUT1 inhibition. We report that genetic or pharmacological inhibition of GLUT1 with BAY-876 impairs the growth of a subset of TNBC cells displaying high glycolytic and lower oxidative phosphorylation (OXPHOS) rates. Pathway enrichment analysis of gene expression data suggests that the functionality of the E2F pathway may reflect to some extent OXPHOS activity. Furthermore, the protein levels of retinoblastoma tumor suppressor (RB1) strongly correlate with the degree of sensitivity to GLUT1 inhibition in TNBC, where RB1-negative cells are insensitive to GLUT1 inhibition. Collectively, our results highlight a strong and targetable RB1-GLUT1 metabolic axis in TNBC and warrant clinical evaluation of GLUT1 inhibition in TNBC patients stratified according to RB1 protein expression levels.


Assuntos
Transportador de Glucose Tipo 1/antagonistas & inibidores , Transportador de Glucose Tipo 1/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 1/genética , Humanos , Camundongos , Fosforilação Oxidativa , Proteômica , Pirazóis/farmacologia , Piridinas/farmacologia , Quinolinas , RNA Mensageiro/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Ubiquitina-Proteína Ligases/genética
17.
Medicine (Baltimore) ; 99(32): e21478, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769881

RESUMO

The aim of current study was to use Weighted Gene Coexpression Network Analysis (WGCNA) to identify hub genes related to the incidence and prognosis of KRAS mutant (MT) lung adenocarcinoma (LUAD).We involved 184 stage IIB to IV LUAD samples and 59 normal lung tissue samples from The Cancer Genome Atlas (TCGA) database. The R package "limma" was used to identify differentially expressed genes (DEGs). WGCNA and survival analyses were performed by R packages "WGCNA" and "survival," respectively. The functional analyses were performed by R package "clusterProfiler" and GSEA software. Network construction and MCODE analysis were performed by Cytoscape_v3.6.1.Totally 2590 KRAS MT specific DEGs were found between LUAD and normal lung tissues, and 10 WGCNA modules were identified. Functional analysis of the key module showed the ribosome biogenesis related terms were enriched. We observed the expression of 8 genes were positively correlated to the worse survival of KRAS MT LUAD patients, the 7 of them were validated by Kaplan-Meier plotter database (kmplot.com/) (thymosin Beta 10 [TMSB10], ribosomal Protein S16 [RPS16], mitochondrial ribosomal protein L27 [MRPL27], cytochrome c oxidase subunit 6A1 [COX6A1], HCLS1-associated protein X-1 [HAX1], ribosomal protein L38 [RPL38], and ATP Synthase Membrane Subunit DAPIT [ATP5MD]). The GSEA analysis found mTOR and STK33 pathways were upregulated in KRAS MT LUAD (P < .05, false discovery rate [FDR] < 0.25).In summary, our study firstly used WGCNA to identify hub genes in the development of KRAS MT LUAD. The identified prognostic factors would be potential biomarkers in clinical use. Further molecular studies are required to confirm the mechanism of those genes in KRAS MT LUAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Redes Reguladoras de Genes/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adenocarcinoma de Pulmão/mortalidade , Biomarcadores Tumorais/genética , Biologia Computacional , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Mutação , Prognóstico , RNA Mensageiro/metabolismo , Análise de Sobrevida
18.
PLoS One ; 15(7): e0233582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735620

RESUMO

The craniofacial developmental disorder Burn-McKeown Syndrome (BMKS) is caused by biallelic variants in the pre-messenger RNA splicing factor gene TXNL4A/DIB1. The majority of affected individuals with BMKS have a 34 base pair deletion in the promoter region of one allele of TXNL4A combined with a loss-of-function variant on the other allele, resulting in reduced TXNL4A expression. However, it is unclear how reduced expression of this ubiquitously expressed spliceosome protein results in craniofacial defects during development. Here we reprogrammed peripheral mononuclear blood cells from a BMKS patient and her unaffected mother into induced pluripotent stem cells (iPSCs) and differentiated the iPSCs into induced neural crest cells (iNCCs), the key cell type required for correct craniofacial development. BMKS patient-derived iPSCs proliferated more slowly than both mother- and unrelated control-derived iPSCs, and RNA-Seq analysis revealed significant differences in gene expression and alternative splicing. Patient iPSCs displayed defective differentiation into iNCCs compared to maternal and unrelated control iPSCs, in particular a delay in undergoing an epithelial-to-mesenchymal transition (EMT). RNA-Seq analysis of differentiated iNCCs revealed widespread gene expression changes and mis-splicing in genes relevant to craniofacial and embryonic development that highlight a dampened response to WNT signalling, the key pathway activated during iNCC differentiation. Furthermore, we identified the mis-splicing of TCF7L2 exon 4, a key gene in the WNT pathway, as a potential cause of the downregulated WNT response in patient cells. Additionally, mis-spliced genes shared common sequence properties such as length, branch point to 3' splice site (BPS-3'SS) distance and splice site strengths, suggesting that splicing of particular subsets of genes is particularly sensitive to changes in TXNL4A expression. Together, these data provide the first insight into how reduced TXNL4A expression in BMKS patients might compromise splicing and NCC function, resulting in defective craniofacial development in the embryo.


Assuntos
Processamento Alternativo , Atresia das Cóanas/patologia , Surdez/congênito , Regulação da Expressão Gênica no Desenvolvimento , Cardiopatias Congênitas/patologia , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Ribonucleoproteína Nuclear Pequena U5/deficiência , Spliceossomos/fisiologia , Apoptose , Diferenciação Celular , Técnicas de Reprogramação Celular , Atresia das Cóanas/genética , Células Clonais , Surdez/genética , Surdez/patologia , Transição Epitelial-Mesenquimal , Éxons/genética , Face/embriologia , Facies , Feminino , Cabeça/embriologia , Cardiopatias Congênitas/genética , Humanos , Crista Neural/citologia , Regiões Promotoras Genéticas/genética , Sítios de Splice de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonucleoproteína Nuclear Pequena U5/genética , Deleção de Sequência , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Via de Sinalização Wnt
19.
Nat Commun ; 11(1): 4061, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792541

RESUMO

Adhesions are fibrotic scars that form between abdominal organs following surgery or infection, and may cause bowel obstruction, chronic pain, or infertility. Our understanding of adhesion biology is limited, which explains the paucity of anti-adhesion treatments. Here we present a systematic analysis of mouse and human adhesion tissues. First, we show that adhesions derive primarily from the visceral peritoneum, consistent with our clinical experience that adhesions form primarily following laparotomy rather than laparoscopy. Second, adhesions are formed by poly-clonal proliferating tissue-resident fibroblasts. Third, using single cell RNA-sequencing, we identify heterogeneity among adhesion fibroblasts, which is more pronounced at early timepoints. Fourth, JUN promotes adhesion formation and results in upregulation of PDGFRA expression. With JUN suppression, adhesion formation is diminished. Our findings support JUN as a therapeutic target to prevent adhesions. An anti-JUN therapy that could be applied intra-operatively to prevent adhesion formation could dramatically improve the lives of surgical patients.


Assuntos
Aderências Teciduais/metabolismo , Aderências Teciduais/patologia , Animais , Benzofenonas/farmacologia , Sistemas CRISPR-Cas , Células Cultivadas , Doxiciclina/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Humanos , Imuno-Histoquímica , Isoxazóis/farmacologia , Lipossomos/metabolismo , Camundongos , Células NIH 3T3 , Parabiose , RNA Mensageiro/metabolismo , Tamoxifeno/farmacologia
20.
Nat Commun ; 11(1): 4106, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796827

RESUMO

Alternative ribosome-rescue factor B (ArfB) rescues ribosomes stalled on non-stop mRNAs by releasing the nascent polypeptide from the peptidyl-tRNA. By rapid kinetics we show that ArfB selects ribosomes stalled on short truncated mRNAs, rather than on longer mRNAs mimicking pausing on rare codon clusters. In combination with cryo-electron microscopy we dissect the multistep rescue pathway of ArfB, which first binds to ribosomes very rapidly regardless of the mRNA length. The selectivity for shorter mRNAs arises from the subsequent slow engagement step, as it requires longer mRNA to shift to enable ArfB binding. Engagement results in specific interactions of the ArfB C-terminal domain with the mRNA entry channel, which activates peptidyl-tRNA hydrolysis by the N-terminal domain. These data reveal how protein dynamics translate into specificity of substrate recognition and provide insights into the action of a putative rescue factor in mitochondria.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Ribossomos/metabolismo , Microscopia Crioeletrônica , RNA Mensageiro/metabolismo , Aminoacil-RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/ultraestrutura , Ribossomos/ultraestrutura
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