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1.
FASEB J ; 38(10): e23639, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38742798

RESUMO

We tested the hypothesis that the biosensor capability of the endometrium is mediated in part, by the effect of different cargo contained in the extracellular vesicles secreted by the conceptus during the peri-implantation period of pregnancy. We transferred Bos taurus taurus embryos of different origin, in vivo (high developmental potential (IV)), in vitro (intermediate developmental potential (IVF)), or cloned (low developmental potential (NT)), into Bos taurus indicus recipients. Extracellular vesicles (EVs) recovered from Day 16 conceptus-conditioned medium were characterized and their microRNA (miRNA) cargo sequenced alongside RNA sequencing of their respective endometria. There were substantial differences in the endometrial response to in vivo versus in vitro and in vivo versus cloned conceptuses (1153 and 334DEGs respectively) with limited differences between in vitro Vs cloned conceptuses (36 DEGs). The miRNA cargo contained in conceptus-derived EVs was similar between all three groups (426 miRNA in common). Only 8 miRNAs were different between in vivo and cloned conceptuses, while only 6 miRNAs were different between in vivo and in vitro-derived conceptuses. Treatment of endometrial epithelial cells with mimic or inhibitors for miR-128 and miR-1298 changed the proteomic content of target cells (96 and 85, respectively) of which mRNAs are altered in the endometrium in vivo (PLXDC2, COPG1, HSPA12A, MCM5, TBL1XR1, and TTF). In conclusion, we have determined that the biosensor capability of the endometrium is mediated in part, by its response to different EVs miRNA cargo produced by the conceptus during the peri-implantation period of pregnancy.


Assuntos
Endométrio , Vesículas Extracelulares , MicroRNAs , Feminino , Endométrio/metabolismo , Endométrio/citologia , Animais , Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , MicroRNAs/genética , Bovinos , Gravidez , Técnicas Biossensoriais/métodos , Implantação do Embrião/fisiologia , Embrião de Mamíferos/metabolismo
2.
RNA ; 27(9): 1082-1101, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34193551

RESUMO

The expression of long noncoding RNAs is highly enriched in the human nervous system. However, the function of neuronal lncRNAs in the cytoplasm and their potential translation remains poorly understood. Here we performed Poly-Ribo-Seq to understand the interaction of lncRNAs with the translation machinery and the functional consequences during neuronal differentiation of human SH-SY5Y cells. We discovered 237 cytoplasmic lncRNAs up-regulated during early neuronal differentiation, 58%-70% of which are associated with polysome translation complexes. Among these polysome-associated lncRNAs, we find 45 small ORFs to be actively translated, 17 specifically upon differentiation. Fifteen of 45 of the translated lncRNA-smORFs exhibit sequence conservation within Hominidea, suggesting they are under strong selective constraint in this clade. The profiling of publicly available data sets revealed that 8/45 of the translated lncRNAs are dynamically expressed during human brain development, and 22/45 are associated with cancers of the central nervous system. One translated lncRNA we discovered is LINC01116, which is induced upon differentiation and contains an 87 codon smORF exhibiting increased ribosome profiling signal upon differentiation. The resulting LINC01116 peptide localizes to neurites. Knockdown of LINC01116 results in a significant reduction of neurite length in differentiated cells, indicating it contributes to neuronal differentiation. Our findings indicate cytoplasmic lncRNAs interact with translation complexes, are a noncanonical source of novel peptides, and contribute to neuronal function and disease. Specifically, we demonstrate a novel functional role for LINC01116 during human neuronal differentiation.


Assuntos
Diferenciação Celular/genética , Neurônios/metabolismo , Polirribossomos/genética , Biossíntese de Proteínas , RNA Longo não Codificante/genética , Sequência de Bases , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citoplasma/genética , Citoplasma/metabolismo , Humanos , Neurônios/citologia , Fases de Leitura Aberta , Polirribossomos/metabolismo , RNA Longo não Codificante/classificação , RNA Longo não Codificante/metabolismo , Análise de Sequência de RNA , Tretinoína/farmacologia
3.
J Clin Immunol ; 41(2): 441-457, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33284430

RESUMO

Biallelic mutations in SLC29A3 cause histiocytosis-lymphadenopathy plus syndrome, also known as H syndrome (HS). HS is a complex disorder, with ~ 25% of patients developing autoinflammatory complications consisting of unexplained fevers, persistently elevated inflammatory markers, and unusual lymphadenopathies, with infiltrating CD68+, S100+, and CD1a- histiocytes, resembling the immunophenotype found in Rosai-Dorfman disease (RDD). We investigated the transcriptomic profiles of monocytes, non-activated (M0), classically activated (M1), and alternatively activated macrophages (M2) in two patients with HS, one without autoinflammatory (HS1) and one with autoinflammatory complications (HS2). RNA sequencing revealed a dysregulated transcriptomic profile in both HS patients compared to healthy controls (HC). HS2, when compared to HS1, had several differentially expressed genes, including genes associated with lymphocytic-histiocytic predominance (e.g. NINL) and chronic immune activation (e.g. B2M). The transcriptomic and cytokine profiles of HS patients were comparable to patients with SAID with high levels of TNF. SERPINA1 gene expression was found to be upregulated in all patients studied. Moreover, higher levels of IFNγ were found in the serum of both HS patients when compared to HC. Gene ontology (GO) enrichment analysis of the DEGs in HS patients revealed the terms "type I IFN," "IFNγ signaling pathway," and "immune responses" as the top 3 most significant terms for monocytes. Gene expression analysis of lymph node biopsies from sporadic and H syndrome-associated RDD suggests common underlying pathological process. In conclusion, monocytes and macrophages from both HS patients showed transcriptomic profiles similar to SAIDs and also uniquely upregulated IFNγ signature. These findings may help find better therapeutic options for this rare disorder.


Assuntos
Contratura/genética , Perda Auditiva Neurossensorial/genética , Histiocitose Sinusal/genética , Histiocitose/genética , Transdução de Sinais/genética , Transcriptoma/genética , Adolescente , Adulto , Doenças Autoimunes/genética , Biomarcadores/metabolismo , Citocinas/genética , Feminino , Expressão Gênica/genética , Histiócitos/metabolismo , Humanos , Inflamação/genética , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Proteínas de Transporte de Nucleosídeos/genética , Adulto Jovem
4.
BMC Vet Res ; 17(1): 262, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34332568

RESUMO

BACKGROUND: Vector-borne diseases (VBDs) impact both human and veterinary medicine and pose special public health challenges. The main bacterial vector-borne pathogens (VBPs) of importance in veterinary medicine include Anaplasma spp., Bartonella spp., Ehrlichia spp., and Spotted Fever Group Rickettsia. Taxon-targeted PCR assays are the current gold standard for VBP diagnostics but limitations on the detection of genetically diverse organisms support a novel approach for broader detection of VBPs. We present a methodology for genetic characterization of VBPs using Next-Generation Sequencing (NGS) and computational approaches. A major advantage of NGS is the ability to detect multiple organisms present in the same clinical sample in an unsupervised (i.e. non-targeted) and semi-quantitative way. The Standard Operating Procedure (SOP) presented here combines industry-standard microbiome analysis tools with our ad-hoc bioinformatic scripts to form a complete analysis pipeline accessible to veterinary scientists and freely available for download and use at https://github.com/eltonjrv/microbiome.westernu/tree/SOP . RESULTS: We tested and validated our SOP by mimicking single, double, and triple infections in genomic canine DNA using serial dilutions of plasmids containing the entire 16 S rRNA gene sequence of (A) phagocytophilum, (B) v. berkhoffii, and E. canis. NGS with broad-range 16 S rRNA primers followed by our bioinformatics SOP was capable of detecting these pathogens in biological replicates of different dilutions. These results illustrate the ability of NGS to detect and genetically characterize multi-infections with different amounts of pathogens in a single sample. CONCLUSIONS: Bloodborne microbiomics & metagenomics approaches may help expand the molecular diagnostic toolbox in veterinary and human medicine. In this paper, we present both in vitro and in silico detailed protocols that can be combined into a single workflow that may provide a significant improvement in VBP diagnostics and also facilitate future applications of microbiome research in veterinary medicine.


Assuntos
Bactérias/isolamento & purificação , Doenças do Cão/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , RNA Ribossômico 16S/genética , Doenças Transmitidas por Vetores/veterinária , Animais , Bactérias/genética , Doenças do Cão/microbiologia , Cães , RNA Bacteriano/genética , Reprodutibilidade dos Testes , Doenças Transmitidas por Vetores/diagnóstico , Doenças Transmitidas por Vetores/microbiologia
5.
Exp Mol Pathol ; 112: 104354, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31837325

RESUMO

In the past decade, research efforts were made to identify molecular biomarkers useful as therapeutic targets in Non-Small Cell Lung Cancer (NSCLC), the most frequent type of lung carcinoma. NSCLC presents different histological subtypes being the most prevalent LUSC (Lung Squamous Cell Cancer) and LUAD (Lung Adenocarcinoma), and only a subset of LUAD patients' present tumors expressing known targetable genetic alterations. Telomeres and its components, including telomerase, the enzyme that replenishes telomeres, have been considered potential cancer biomarkers due to their crucial role in cell proliferation and genome stability. Our study aims to quantify expression changes affecting telomere-associated genes and ncRNAs associated with telomere regulation and maintenance in NSCLC. We first assessed the transcriptome (RNA-Seq) data of NSCLC patients from The Cancer Genome Atlas (TCGA) and then we tested the expression of telomere-associated genes and telomeric ncRNAs (TERC, telomerase RNA component, and TERRA, telomere repeat-containing RNA) in Brazilian NCSLC patient samples by quantitative RT-PCR, using matched normal adjacent tissue samples as the control. We also estimated the mean size of terminal restriction fragments (TRF) of some Brazilian NSCLC patients using telomeric Southern blot. The TCGA analysis identified alterations in the expression profile of TERT and telomere damage repair genes, mainly in the LUSC subtype. The study of Brazilian NSCLC samples by RT-qPCR showed that LUSC and LUAD express high amounts of TERT and that although the mean TRF size of tumor samples was shorter compared to normal cells, telomeres in NSCLC are probably maintained by telomerase. Also, the expression analysis of Brazilian NSCLC samples identified statistically significant alterations in the expression of genes involved with telomere damage repair, as well as in TERC and TERRA, mainly in the LUSC subtype. We, therefore, concluded that telomere maintenance genes are significantly deregulated in NSCLC, representing potential biomarkers in the LUSC subtype.


Assuntos
Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias de Células Escamosas/genética , Telômero/genética , Adenocarcinoma/classificação , Adenocarcinoma/patologia , Biomarcadores Tumorais/genética , Brasil , Carcinoma Pulmonar de Células não Pequenas/classificação , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ciclo Celular/genética , Proliferação de Células/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias de Células Escamosas/classificação , Neoplasias de Células Escamosas/patologia , Proteínas Nucleares/genética , RNA/genética , RNA Longo não Codificante/genética , Complexo Shelterina , Telomerase/genética , Proteínas de Ligação a Telômeros/genética , Fatores de Transcrição/genética , Transcriptoma/genética
6.
Int J Mol Sci ; 21(8)2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32325999

RESUMO

Interferon Tau (IFNT), the conceptus-derived pregnancy recognition signal in cattle, significantly modifies the transcriptome of the endometrium. However, the endometrium also responds to IFNT-independent conceptus-derived products. The aim of this study was to determine what proteins are produced by the bovine conceptus that may facilitate the pregnancy recognition process in cattle. We analysed by mass spectrometry the proteins present in conceptus-conditioned media (CCM) after 6 h culture of Day 16 bovine conceptuses (n = 8) in SILAC media (arginine- and lysine-depleted media supplemented with heavy isotopes) and the protein content of extracellular vesicles (EVs) isolated from uterine luminal fluid (ULF) of Day 16 pregnant (n = 7) and cyclic (n = 6) cross-bred heifers on day 16. In total, 11,122 proteins were identified in the CCM. Of these, 5.95% (662) had peptides with heavy labelled amino acids, i.e., de novo synthesised by the conceptuses. None of these proteins were detected in the EVs isolated from ULF. Pregnancy-associated glycoprotein 11, Trophoblast Kunitz domain protein 1 and DExD-Box Helicase 39A were de novo produced and present in the CCM from all conceptuses and in previously published CCM data following 6 and 24 h. A total of 463 proteins were present in the CCM from all the conceptuses in the present study, and after 6 and 24 h culture in a previous study, while expression of their transcripts was not detected in endometrium indicating that they are likely conceptus-derived. Of the proteins present in the EVs, 67 were uniquely identified in ULF from pregnant heifers; 35 of these had been previously reported in CCM from Day 16 conceptuses. This study has narrowed a set of conceptus-derived proteins that may be involved in EV-mediated IFNT-independent embryo-maternal communication during pregnancy recognition in cattle.


Assuntos
Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Biossíntese de Proteínas , Animais , Bovinos , Biologia Computacional/métodos , Endométrio/metabolismo , Vesículas Extracelulares/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Gravidez , Reprodutibilidade dos Testes , Fatores de Tempo , Transcriptoma
7.
RNA Biol ; 16(5): 639-660, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30689499

RESUMO

Leishmaniasis is a worldwide public health problem caused by protozoan parasites of the genus Leishmania. Leishmania braziliensis is the most important species responsible for tegumentary leishmaniases in Brazil. An understanding of the molecular mechanisms underlying the success of this parasite is urgently needed. An in-depth study on the modulation of gene expression across the life cycle stages of L. braziliensis covering coding and noncoding RNAs (ncRNAs) was missing and is presented herein. Analyses of differentially expressed (DE) genes revealed that most prominent differences were observed between the transcriptomes of insect and mammalian proliferative forms (6,576 genes). Gene ontology (GO) analysis indicated stage-specific enriched biological processes. A computational pipeline and 5 ncRNA predictors allowed the identification of 11,372 putative ncRNAs. Most of the DE ncRNAs were found between the transcriptomes of insect and mammalian proliferative stages (38%). Of the DE ncRNAs, 295 were DE in all three stages and displayed a wide range of lengths, chromosomal distributions and locations; many of them had a distinct expression profile compared to that of their protein-coding neighbors. Thirty-five putative ncRNAs were submitted to northern blotting analysis, and one or more hybridization-positive signals were observed in 22 of these ncRNAs. This work presents an overview of the L. braziliensis transcriptome and its adjustments throughout development. In addition to determining the general features of the transcriptome at each life stage and the profile of protein-coding transcripts, we identified and characterized a variety of noncoding transcripts. The novel putative ncRNAs uncovered in L. braziliensis might be regulatory elements to be further investigated.


Assuntos
Perfilação da Expressão Gênica/métodos , Leishmania braziliensis/crescimento & desenvolvimento , RNA de Protozoário/genética , Análise de Sequência de RNA/métodos , Animais , Brasil , Biologia Computacional/métodos , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Humanos , Insetos/parasitologia , Leishmania braziliensis/genética , Mamíferos/parasitologia , RNA não Traduzido/genética
8.
Invest New Drugs ; 35(1): 26-36, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27785591

RESUMO

Medulloblastoma (MB) is the most common solid tumor among pediatric patients and corresponds to 20 % of all pediatric intracranial tumors in this age group. Its treatment currently involves significant side effects. Epigenetic changes such as DNA methylation may contribute to its development and progression. DNA methyltransferase (DNMT) inhibitors have shown promising anticancer effects. The agent Zebularine acts as an inhibitor of DNA methylation and shows low toxicity and high efficacy, being a promising adjuvant agent for anti-cancer chemotherapy. Several studies have reported its effects on different types of tumors; however, there are no studies reporting its effects on MB. We analyzed its potential anticancer effects in four pediatric MB cell lines. The treatment inhibited proliferation and clonogenicity, increased the apoptosis rate and the number of cells in the S phase (p < 0.05), as well as the expression of p53, p21, and Bax, and decreased cyclin A, Survivin and Bcl-2 proteins. In addition, the combination of zebularine with the chemotherapeutic agents vincristine and cisplatin resulted in synergism and antagonism, respectively. Zebularine also modulated the activation of the SHH pathway, reducing SMO and GLI1 levels and one of its targets, PTCH1, without changing SUFU levels. A microarray analysis revealed different pathways modulated by the drug, including the Toll-Like Receptor pathway and high levels of the BATF2 gene. The low expression of this gene was associated with a worse prognosis in MB. Taken together, these data suggest that Zebularine may be a potential drug for further in vivo studies of MB treatment.


Assuntos
Antineoplásicos/farmacologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Neoplasias Cerebelares/tratamento farmacológico , Citidina/análogos & derivados , Metilases de Modificação do DNA/antagonistas & inibidores , Meduloblastoma/tratamento farmacológico , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Apoptose/efeitos dos fármacos , Biomarcadores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Criança , Pré-Escolar , Cisplatino/farmacologia , Citidina/farmacologia , Metilases de Modificação do DNA/metabolismo , Interações Medicamentosas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Recém-Nascido , Masculino , Meduloblastoma/genética , Meduloblastoma/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Vincristina/farmacologia , Adulto Jovem
9.
Anticancer Drugs ; 28(6): 634-644, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28410270

RESUMO

Adrenocortical tumor (ACT) is a malignancy with a low incidence rate and the current therapy for advanced disease has a limited impact on overall patient survival. A previous study from our group suggested that elevated expression of aurora-A and aurora-B is associated with poor outcome in childhood ACT. Similar results were also reported for adult ACTs. The present in-vitro study shows that AMG 900 inhibits aurora kinases in adrenocortical carcinoma cells. AMG 900 inhibited cell proliferation in NCI-H295 cells as well as in the ACT primary cultures and caused apoptosis in the cell line NCI-H295. Furthermore, it potentialized the mitotane, doxorubicin, and etoposide effects on apoptosis induction and acted synergistically with mitotane and doxorubicin in the inhibition of proliferation. In addition, we found that AMG 900 activated Notch signaling and rendered the cells sensitive to the combination of AMG 900 and Notch signaling inhibition. Altogether, these data show that aurora kinases inhibition using AMG 900 may be an adjuvant therapy to treat patients with invasive or recurrent adrenocortical carcinomas.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Carcinoma Adrenocortical/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Neoplasias do Córtex Suprarrenal/enzimologia , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/enzimologia , Carcinoma Adrenocortical/patologia , Aurora Quinases/antagonistas & inibidores , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Histonas/metabolismo , Humanos , Mitotano/administração & dosagem , Mitotano/farmacologia , Fosforilação/efeitos dos fármacos , Ftalazinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem
10.
BMC Genomics ; 16: 151, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25764986

RESUMO

BACKGROUND: Leishmania use exosomes to communicate with their mammalian hosts and these secreted vesicles appear to contribute to pathogenesis by delivering protein virulence factors to macrophages. In other eukaryotes, exosomes were found to carry RNA cargo, such as mRNAs and small non-coding RNAs, capable of altering recipient cell phenotype. Whether leishmania exosomes also contain RNAs which they are able to deliver to bystander cells is not known. Here, we show that leishmania exosomes indeed contain RNAs and compare and contrast the RNA content of exosomes released by Leishmania donovani and Leishmania braziliensis. RESULTS: We purified RNA from exosomes collected from axenic amastigote culture supernatant and found that when compared with total leishmania RNA, exosomes mainly contained short RNA sequences. Exosomes with intact membranes were capable of protecting their RNA cargo from degradation by RNase. Moreover, exosome RNA cargo was delivered to host cell cytoplasm in vitro. Sequencing of exosomal RNA indicated that the majority of cargo sequences were derived from non-coding RNA species such as rRNA and tRNA. In depth analysis revealed the presence of tRNA-derived small RNAs, a novel RNA type with suspected regulatory functions. Northern blotting confirmed the specific and selective enrichment of tRNA-derived small RNAs in exosomes. We also identified a number of novel transcripts, which appeared to be specifically enriched in exosomes compared to total cell RNA. In addition, we observed the presence of sequences mapping to siRNA-coding regions in L. braziliensis , but not in L. donovani exosomes. CONCLUSIONS: These results show that leishmania exosomes are selectively and specifically enriched in small RNAs derived almost exclusively from non-coding RNAs. These exosomes are competent to deliver their cargo of novel, potential small regulatory RNAs to macrophages where they may influence parasite-host cell interactions. The remarkably high degree of congruence in exosomal RNA content between L. donovani and L. braziliensis, argues for the presence of a conserved mechanism for exosomal RNA packaging in leishmania. These findings open up a new avenue of research on non-canonical, small RNA pathways in this trypanosomatid, which may elucidate pathogenesis and identify novel therapeutic approaches.


Assuntos
Exossomos/genética , Leishmaniose Visceral/genética , Pequeno RNA não Traduzido/genética , RNA de Transferência/genética , Animais , Sequência de Bases , Leishmania braziliensis/genética , Leishmania braziliensis/patogenicidade , Leishmania donovani/genética , Leishmania donovani/patogenicidade , Leishmaniose Visceral/parasitologia , MicroRNAs/genética , RNA Mensageiro/genética
11.
BMC Genomics ; 15: 911, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25331479

RESUMO

BACKGROUND: Trypanosoma brucei subspecies infect humans and animals in sub-Saharan Africa. This early diverging eukaryote shows many novel features in basic biological processes, including the use of polycistronic transcription to generate all protein-coding mRNAs. Therefore we hypothesized that translational control provides a means to tune gene expression during parasite development in mammalian and fly hosts. RESULTS: We used ribosome profiling to examine genome-wide protein synthesis in animal-derived slender bloodstream forms and cultured procyclic (insect midgut) forms. About one-third of all CDSs showed statistically significant regulation of protein production between the two stages. Of these, more than two-thirds showed a change in translation efficiency, but few appeared to be controlled by this alone. Ribosomal proteins were translated poorly, especially in animal-derived parasites. A disproportionate number of metabolic enzymes were up-regulated at the mRNA level in procyclic forms, as were variant surface glycoproteins in bloodstream forms. Comparison with cultured bloodstream forms from another strain revealed stage-specific changes in gene expression that transcend strain and growth conditions. Genes with upstream ORFs had lower mean translation efficiency, but no evidence was found for involvement of uORFs in stage-regulation. CONCLUSIONS: Ribosome profiling revealed that differences in the production of specific proteins in T. brucei bloodstream and procyclic forms are more extensive than predicted by analysis of mRNA abundance. While in vivo and in vitro derived bloodstream forms from different strains are more similar to one another than to procyclic forms, they showed many differences at both the mRNA and protein production level.


Assuntos
Perfilação da Expressão Gênica/métodos , Biossíntese de Proteínas , Proteínas de Protozoários/genética , Proteínas Ribossômicas/genética , Trypanosoma brucei brucei/crescimento & desenvolvimento , Animais , Regulação da Expressão Gênica no Desenvolvimento , RNA Mensageiro/genética , RNA de Protozoário/genética , Trypanosoma brucei brucei/enzimologia , Trypanosoma brucei brucei/genética
12.
Sci Total Environ ; 931: 172507, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38657818

RESUMO

Dumped Chromium Ore Processing Residue (COPR) at legacy sites poses a threat to health through leaching of toxic Cr(VI) into groundwater. Previous work implicates microbial activity in reducing Cr(VI) to less mobile and toxic Cr(III), but the mechanism has not been explored. To address this question a combined metagenomic and geochemical study was undertaken. Soil samples from below the COPR waste were used to establish anaerobic microcosms which were challenged with Cr(VI), with or without acetate as an electron donor, and incubated for 70 days. Cr was rapidly reduced in both systems, which also reduced nitrate, nitrite then sulfate, but this sequence was accelerated in the acetate amended microcosms. 16S rRNA gene sequencing revealed that the original soil sample was diverse but both microcosm systems became less diverse by the end of the experiment. A high proportion of 16S rRNA gene reads and metagenome-assembled genomes (MAGs) with high completeness could not be taxonomically classified, highlighting the distinctiveness of these alkaline Cr impacted systems. Examination of the coding capacity revealed widespread capability for metal tolerance and Fe uptake and storage, and both populations possessed metabolic capability to degrade a wide range of organic molecules. The relative abundance of genes for fatty acid degradation was 4× higher in the unamended compared to the acetate amended system, whereas the capacity for dissimilatory sulfate metabolism was 3× higher in the acetate amended system. We demonstrate that naturally occurring in situ bacterial populations have the metabolic capability to couple acetate oxidation to sequential reduction of electron acceptors which can reduce Cr(VI) to less mobile and toxic Cr(III), and that microbially produced sulfide may be important in reductive precipitation of chromate. This capability could be harnessed to create a Cr(VI) trap-zone beneath COPR tips without the need to disturb the waste.


Assuntos
Cromo , RNA Ribossômico 16S , Microbiologia do Solo , Cromo/metabolismo , Metagenoma , Oxirredução , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Água Subterrânea/microbiologia , Água Subterrânea/química , Bactérias/metabolismo
13.
Commun Biol ; 7(1): 704, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851817

RESUMO

Aspergillus fumigatus represents a public health problem due to the high mortality rate in immunosuppressed patients and the emergence of antifungal-resistant isolates. Protein acetylation is a crucial post-translational modification that controls gene expression and biological processes. The strategic manipulation of enzymes involved in protein acetylation has emerged as a promising therapeutic approach for addressing fungal infections. Sirtuins, NAD+-dependent lysine deacetylases, regulate protein acetylation and gene expression in eukaryotes. However, their role in the human pathogenic fungus A. fumigatus remains unclear. This study constructs six single knockout strains of A. fumigatus and a strain lacking all predicted sirtuins (SIRTKO). The mutant strains are viable under laboratory conditions, indicating that sirtuins are not essential genes. Phenotypic assays suggest sirtuins' involvement in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. Deletion of sirE attenuates virulence in murine and Galleria mellonella infection models. The absence of SirE alters the acetylation status of proteins, including histones and non-histones, and triggers significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.


Assuntos
Aspergilose , Aspergillus fumigatus , Sirtuínas , Aspergillus fumigatus/patogenicidade , Aspergillus fumigatus/genética , Aspergillus fumigatus/enzimologia , Sirtuínas/genética , Sirtuínas/metabolismo , Virulência , Animais , Camundongos , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Acetilação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Mariposas/microbiologia
14.
Nat Commun ; 15(1): 3138, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605034

RESUMO

The carboxy-terminus of the spliceosomal protein PRPF8, which regulates the RNA helicase Brr2, is a hotspot for mutations causing retinitis pigmentosa-type 13, with unclear role in human splicing and tissue-specificity mechanism. We used patient induced pluripotent stem cells-derived cells, carrying the heterozygous PRPF8 c.6926 A > C (p.H2309P) mutation to demonstrate retinal-specific endophenotypes comprising photoreceptor loss, apical-basal polarity and ciliary defects. Comprehensive molecular, transcriptomic, and proteomic analyses revealed a role of the PRPF8/Brr2 regulation in 5'-splice site (5'SS) selection by spliceosomes, for which disruption impaired alternative splicing and weak/suboptimal 5'SS selection, and enhanced cryptic splicing, predominantly in ciliary and retinal-specific transcripts. Altered splicing efficiency, nuclear speckles organisation, and PRPF8 interaction with U6 snRNA, caused accumulation of active spliceosomes and poly(A)+ mRNAs in unique splicing clusters located at the nuclear periphery of photoreceptors. Collectively these elucidate the role of PRPF8/Brr2 regulatory mechanisms in splicing and the molecular basis of retinal disease, informing therapeutic approaches.


Assuntos
Sítios de Splice de RNA , Retinose Pigmentar , Spliceossomos , Humanos , Spliceossomos/genética , Spliceossomos/metabolismo , Proteômica , Splicing de RNA/genética , Processamento Alternativo/genética , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , RNA Mensageiro/metabolismo , Mutação , DNA Helicases/metabolismo , Proteínas de Ligação a RNA/metabolismo
15.
Nat Commun ; 14(1): 300, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653366

RESUMO

Historically, ribosomes were viewed as unchanged homogeneous macromolecular machines with no regulatory capacity for mRNA translation. An emerging concept is that heterogeneity of ribosomal composition exists, exerting a regulatory function or specificity in translational control. This is supported by recent discoveries identifying compositionally distinct specialised ribosomes that actively regulate mRNA translation. Viruses lack their own translational machinery and impose high translational demands on the host during replication. We explore the possibility that KSHV manipulates ribosome biogenesis producing specialised ribosomes which preferentially translate viral transcripts. Quantitative proteomic analysis identified changes in the stoichiometry and composition of precursor ribosomal complexes during the switch from latent to lytic replication. We demonstrate the enhanced association of ribosomal biogenesis factors BUD23 and NOC4L, and the KSHV ORF11 protein, with small ribosomal subunit precursor complexes during lytic replication. BUD23 depletion resulted in significantly reduced viral gene expression, culminating in dramatic reduction of infectious virion production. Ribosome profiling demonstrated BUD23 is essential for reduced association of ribosomes with KSHV uORFs in late lytic genes, required for the efficient translation of the downstream coding sequence. Results provide mechanistic insights into KSHV-mediated manipulation of cellular ribosome composition inducing a population of specialised ribosomes facilitating efficient translation of viral mRNAs.


Assuntos
Herpesvirus Humano 8 , Herpesvirus Humano 8/genética , Replicação Viral/genética , Proteômica , Ribossomos/genética , Regulação Viral da Expressão Gênica
16.
bioRxiv ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37808717

RESUMO

Protein acetylation is a crucial post-translational modification that controls gene expression and a variety of biological processes. Sirtuins, a prominent class of NAD + -dependent lysine deacetylases, serve as key regulators of protein acetylation and gene expression in eukaryotes. In this study, six single knockout strains of fungal pathogen Aspergillus fumigatus were constructed, in addition to a strain lacking all predicted sirtuins (SIRTKO). Phenotypic assays suggest that sirtuins are involved in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. AfsirE deletion resulted in attenuation of virulence, as demonstrated in murine and Galleria infection models. The absence of AfSirE leads to altered acetylation status of proteins, including histones and non-histones, resulting in significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.

18.
Endocrinology ; 162(6)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33693651

RESUMO

The molecular interactions between the maternal environment and the developing embryo are key for early pregnancy success and are influenced by factors such as maternal metabolic status. Our understanding of the mechanism(s) through which these individual nutritional stressors alter endometrial function and the in utero environment for early pregnancy success is, however, limited. Here we report, for the first time, the use of an endometrium-on-a-chip microfluidics approach to produce a multicellular endometrium in vitro. Isolated endometrial cells (epithelial and stromal) from the uteri of nonpregnant cows in the early luteal phase (Days 4-7) were seeded in the upper chamber of the device (epithelial cells; 4-6 × 104 cells/mL) and stromal cells seeded in the lower chamber (1.5-2 × 104 cells/mL). Exposure of cells to different concentrations of glucose (0.5, 5.0, or 50 mM) or insulin (Vehicle, 1 or 10 ng/mL) was performed at a flow rate of 1 µL/minute for 72 hours. Quantitative differences in the cellular transcriptome and the secreted proteome of in vitro-derived uterine luminal fluid were determined by RNA-sequencing and tandem mass tagging mass spectrometry, respectively. High glucose concentrations altered 21 and 191 protein-coding genes in epithelial and stromal cells, respectively (P < .05), with a dose-dependent quantitative change in the protein secretome (1 and 23 proteins). Altering insulin concentrations resulted in limited transcriptional changes including transcripts for insulin-like binding proteins that were cell specific but altered the quantitative secretion of 196 proteins. These findings highlight 1 potential mechanism by which changes to maternal glucose and insulin alter uterine function.


Assuntos
Endométrio/efeitos dos fármacos , Glucose/farmacologia , Insulina/farmacologia , Dispositivos Lab-On-A-Chip , Animais , Bovinos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Células Cultivadas , Embrião de Mamíferos , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Endométrio/citologia , Endométrio/metabolismo , Feminino , Perfilação da Expressão Gênica/instrumentação , Perfilação da Expressão Gênica/métodos , Gravidez , Cultura Primária de Células/instrumentação , Cultura Primária de Células/métodos , Proteoma/efeitos dos fármacos , Proteoma/metabolismo , Proteômica/instrumentação , Proteômica/métodos , Via Secretória/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
19.
Trends Parasitol ; 37(9): 815-830, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33994102

RESUMO

Protein lysine acetylation has emerged as a major regulatory post-translational modification in different organisms, present not only on histone proteins affecting chromatin structure and gene expression but also on nonhistone proteins involved in several cellular processes. The same scenario was observed in protozoan parasites after the description of their acetylomes, indicating that acetylation might regulate crucial biological processes in these parasites. The demonstration that glycolytic enzymes are regulated by acetylation in protozoans shows that this modification might regulate several other processes implicated in parasite survival and adaptation during the life cycle, opening the chance to explore the regulatory acetylation machinery of these parasites as drug targets for new treatment development.


Assuntos
Eucariotos , Proteínas de Protozoários , Acetilação , Eucariotos/enzimologia , Eucariotos/genética , Processamento de Proteína Pós-Traducional , Proteínas de Protozoários/metabolismo
20.
Int J Biol Macromol ; 174: 573-586, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33548324

RESUMO

Telomeres from different eukaryotes, including trypanosomatids, are transcribed into TERRA noncoding RNAs, crucial in regulating chromatin deposition and telomere length. TERRA is transcribed from the C-rich subtelomeric strand towards the 3'-ends of the telomeric array. Using bioinformatics, we confirmed the presence of subtelomeric splice acceptor sites at all L. major chromosome ends. Splice leader sequences positioned 5' upstream of L. major chromosomes subtelomeres were then mapped using SL-RNA-Seq libraries constructed from three independent parasite life stages and helped confirm TERRA expression from several chromosomes ends. Northern blots and RT-qPCR validated the results showing that L. major TERRA is processed by trans-splicing and polyadenylation coupled reactions. The number of transcripts varied with the parasite's life stage and continuous passages, being more abundant in the infective forms. However, no putative subtelomeric promoters involved in TERRA's transcriptional regulation were detected. In contrast, the observed changes in parasite's telomere length during development, suggest that differences in telomeric base J levels may control TERRA transcription in L. major. Also, TERRA-R loops' detection, mainly in the infective forms, was suggestive of TERRA's involvement in telomere protection. Therefore, Leishmania TERRA shares conserved features with other eukaryotes and advances new telomere specific functions in a Public Health-impacting parasite.


Assuntos
Clonagem Molecular/métodos , Perfilação da Expressão Gênica/métodos , Leishmania major/crescimento & desenvolvimento , Fatores de Transcrição/genética , Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Leishmania major/genética , Leishmania major/metabolismo , Poliadenilação , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Splicing de RNA , Análise de Sequência de RNA , Telômero/genética , Fatores de Transcrição/metabolismo
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