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1.
Emerg Microbes Infect ; 11(1): 428-437, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34842509

RESUMO

As next-generation pathogen detection methods, CRISPR-Cas-based detection methods can perform single-nucleotide polymorphism (SNP) level detection with high sensitivity and good specificity. They do not require any particular equipment, which opens up new possibilities for the accurate detection and identification of Bacillus anthracis. In this study, we developed a complete detection system for B. anthracis based on Cas12a. We used two chromosomally located SNP targets and two plasmid targets to identify B. anthracis with high accuracy. The CR5 target is completely new. The entire detection process can be completed within 90 min without electrical power and with single-copy level sensitivity. We also developed an unaided-eye visualization system based on G4-DNAzyme for use with our CRISPR-Cas12a detection system. This visualization system has good prospects for deployment in field-based point-of-care detection. We used the antisense nucleic acid CatG4R as the detection probe, which showed stronger resistance to interference from components of the solution. CatG4R can also be designed as an RNA molecule for adaptation to Cas13a detection, thereby broadening the scope of the detection system.


Assuntos
Antraz/diagnóstico , Bacillus anthracis/genética , Proteínas de Bactérias/genética , Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas/genética , DNA Catalítico/genética , Endodesoxirribonucleases/genética , Elementos Antissenso (Genética)/genética , Bacillus anthracis/isolamento & purificação , Proteínas de Bactérias/metabolismo , Proteínas Associadas a CRISPR/metabolismo , DNA Bacteriano/genética , Endodesoxirribonucleases/metabolismo , Quadruplex G , Plasmídeos/genética
2.
Carcinogenesis ; 42(11): 1347-1356, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34665859

RESUMO

Substantial evidence highlighted the critical role of long non-coding RNAs (lncRNA) in driving hepatocarcinogenesis. We hypothesized that functional variants in genome-wide association studies (GWASs) associated loci might alter the expression levels of lncRNAs and contribute to the development of hepatocellular carcinoma (HCC). Here, we prioritized potentially cis-expression quantitative trait loci-based single nucleotide polymorphism (SNP)-lncRNA association together with the physical interaction by the analyses from Hi-C data in GWAS loci of chronic hepatitis B and HCC. Subsequently, by leveraging two-stage case-control study (1738 hepatitis B [HBV]) related HCC cases and 1988 HBV persistent carriers) and biological assays, we identified that rs2647046 was significantly associated with HCC risk (odds ratio = 1.26, 95% CI = 1.11 to 1.43, P = 4.14 × 10-4). Luciferase reporter assays and electrophoretic mobility shift assays showed that rs2647046 A allele significantly increased transcriptional activity via influencing transcript factor binding affinity. Allele-specific chromosome conformation capture assays revealed that enhancer with rs2647046 interacted with the HLA-DQB1-AS1 promoter to allele-specifically influence its expression by CTCF-mediated long-range loop. Cell proliferation assays indicated that HLA-DQB1-AS1 is a potential oncogene in HCC. Our study showed HLA-DQB1-AS1 regulated by a causal SNP in a long-range interaction manner conferred the susceptibility to HCC, suggesting an important mechanism of modulating lncRNA expression for risk-associated SNPs in the etiology of HCC.


Assuntos
Elementos Antissenso (Genética)/genética , Carcinoma Hepatocelular/genética , Elementos Facilitadores Genéticos , Cadeias beta de HLA-DQ/metabolismo , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Cadeias beta de HLA-DQ/genética , Humanos , Neoplasias Hepáticas/patologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
3.
Biomed Pharmacother ; 142: 112051, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34426254

RESUMO

Brain-derived neurotrophic factor-antisense (BDNF-AS) is a long non-coding RNA with tens of alternatively spliced variants being transcribed from 11p14 cytogenetic band. As a naturally occurring anti-sense, it regulates expression of BDNF, a factor which as essential roles in the pathoetiology of neurodevelopmental diseases. Notably, BDNF-AS has been reported to be down-regulated in colorectal cancer, osteosarcoma, esophageal cancer, glioblastoma, prostate cancer, cervical cancer and breast cancer. This lncRNA has direct/indirect functional interactions with GSK-3ß, EZH2, miR-214, PABPC1, RAX2, DLG5, p53 and ADAR as well as RNH1/TRIM21/mTOR signaling. In prostate and breast cancers, down-regulation of BDNF-AS has been associated with poor clinical outcome. In the present review, we assessed the existing literature on the role of BDNF-AS in this process and summarized the available data in three distinct sections based of the methodology of experiments and source of expression assays. We also summarized the role of BDNF-AS in non-neoplastic conditions.


Assuntos
Elementos Antissenso (Genética)/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Neoplasias/genética , Transtornos do Neurodesenvolvimento/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , Humanos
4.
Carcinogenesis ; 42(10): 1270-1280, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34255057

RESUMO

Increasing studies have indicated the critical roles of long non-coding RNAs (lncRNAs) in the tumorigenesis of cancers. LncRNA AGAP2 antisense RNA 1 (AGAP2-AS1) can serve as an oncogenic role in some cancers, including prostate cancer (PCa). However, the underling mechanism of such lncRNA in PCa has not been fully studied. Therefore, it is meaningful to investigate the role and underlying mechanism of AGAP2-AS1 in PCa. AGAP2-AS1 was confirmed to be highly expressed in PCa cells. Functionally, AGAP2-AS1 silencing inhibited cell proliferation, migration, invasion and epithelial-mesenchymal transition process and induced apoptosis. According to mechanism assays, AGAP2-AS1 sponged miR-628-5p, which was found to restrain PCa cell growth. Besides, FOXP2 was identified as a target gene of miR-628-5p, and its expression was negatively regulated by miR-628-5p and positively modulated by AGAP2-AS1. Importantly, we found that FOXP2 could function as the upstream gene of AGAP2-AS1. Through rescue experiments, we discovered that FOXP2 up-regulation countered AGAP2-AS1 knockdown-mediated inhibition on PCa cell growth. Finally, it was found that AGAP2-AS1 could activate WNT pathway, and LiCl could reverse the influence of AGAP2-AS1 on PCa biological behaviors. To conclude, AGAP2-AS1/miR-628-5p/FOXP2 feedback loop facilitated PCa cell growth via activating WNT pathway.


Assuntos
Elementos Antissenso (Genética)/genética , Fatores de Transcrição Forkhead/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Via de Sinalização Wnt , Proliferação de Células , Transição Epitelial-Mesenquimal , Proteínas de Ligação ao GTP/genética , Proteínas Ativadoras de GTPase/genética , Humanos , Masculino , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/metabolismo
5.
Blood ; 138(15): 1345-1358, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34010414

RESUMO

The blood system serves as a key model for cell differentiation and cancer. It is orchestrated by precise spatiotemporal expression of crucial transcription factors. One of the key master regulators in the hematopoietic systems is PU.1. Reduced levels of PU.1 are characteristic for human acute myeloid leukemia (AML) and are known to induce AML in mouse models. Here, we show that transcriptional downregulation of PU.1 is an active process involving an alternative promoter in intron 3 that is induced by RUNX transcription factors driving noncoding antisense transcription. Core-binding factor (CBF) fusions RUNX1-ETO and CBFß-MYH11 in t(8;21) and inv(16) AML, respectively, activate the PU.1 antisense promoter that results in a shift from sense toward antisense transcription and myeloid differentiation blockade. In patients with CBF-AML, we found that an elevated antisense/sense transcript and promoter accessibility ratio represents a hallmark compared with normal karyotype AML or healthy CD34+ cells. Competitive interaction of an enhancer with the proximal or the antisense promoter forms a binary on/off switch for either myeloid or T-cell development. Leukemic CBF fusions thus use a physiological mechanism used by T cells to decrease sense transcription. Our study is the first example of a sense/antisense promoter competition as a crucial functional switch for gene expression perturbation by oncogenes. Hence, this disease mechanism reveals a previously unknown Achilles heel for future precise therapeutic targeting of oncogene-induced chromatin remodeling.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Elementos Antissenso (Genética)/genética , Linhagem Celular Tumoral , Fusão Gênica , Humanos , Proteínas de Fusão Oncogênica/genética , Regiões Promotoras Genéticas , Proteína 1 Parceira de Translocação de RUNX1/genética , Células Tumorais Cultivadas
6.
Sci Rep ; 11(1): 8808, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888812

RESUMO

Tyrosine kinase inhibitor is an effective chemo-therapeutic drug against tumors with deregulated EGFR pathway. Recently, a genetic variant rs10251977 (G>A) in exon 20 of EGFR reported to act as a prognostic marker for HNSCC. Genotyping of this polymorphism in oral cancer patients showed a similar frequency in cases and controls. EGFR-AS1 expressed significantly high level in tumors and EGFR-A isoform expression showed significant positive correlation (r = 0.6464, p < 0.0001) with reference to EGFR-AS1 expression levels, consistent with larger TCGA HNSCC tumor dataset. Our bioinformatic analysis showed enrichment of alternative splicing marks H3K36me3 and presence of intronic polyA sites spanning around exon 15a and 15b of EGFR facilitates skipping of exon 15b, thereby promoting the splicing of EGFR-A isoform. In addition, high level expression of PTBP1 and its binding site in EGFR and EGFR-AS1 enhances the expression of EGFR-A isoform (r = 0.7404, p < 0.0001) suggesting that EGFR-AS1 expression modulates the EGFR-A and D isoforms through alternative splicing. In addition, this polymorphism creates a binding site for miR-891b in EGFR-AS1 and may negatively regulate the EGFR-A. Collectively, our results suggested the presence of genetic variant in EGFR-AS1 modulates the expression of EGFR-D and A isoforms.


Assuntos
Elementos Antissenso (Genética)/genética , Variação Genética , Isoformas de Proteínas/genética , Linhagem Celular Tumoral , Receptores ErbB/genética , Genótipo , Humanos , Neoplasias Bucais/genética
7.
Biochem Pharmacol ; 187: 114394, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33388283

RESUMO

Nanobodies (VHHs) are the single variable immunoglobulin domains of heavy chain antibodies (hcAbs) that naturally occur in alpacas and other camelids. The two variable domains of conventional antibodies typically interact via a hydrophobic interface. In contrast, the corresponding surface area of nanobodies is hydrophilic, rendering these single immunoglobulin domains highly soluble, robust to harsh environments, and exceptionally easy to format into bispecific reagents. In homage to Geoffrey Burnstock, the pioneer of purinergic signaling, we provide a brief history of nanobody-mediated modulation of purinergic signaling, using our nanobodies targeting P2X7 and the NAD+-metabolizing ecto-enzymes CD38 and ARTC2.2 as examples.


Assuntos
Elementos Antissenso (Genética)/metabolismo , Receptores Purinérgicos/metabolismo , Transdução de Sinais/fisiologia , Anticorpos de Domínio Único/metabolismo , Sequência de Aminoácidos , Animais , Elementos Antissenso (Genética)/administração & dosagem , Elementos Antissenso (Genética)/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Estrutura Terciária de Proteína , Agonistas Purinérgicos/administração & dosagem , Antagonistas Purinérgicos/administração & dosagem , Receptores Purinérgicos/genética , Transdução de Sinais/efeitos dos fármacos , Anticorpos de Domínio Único/administração & dosagem , Anticorpos de Domínio Único/genética
8.
Arch Virol ; 165(10): 2373-2377, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761270
9.
Neuron ; 107(2): 292-305.e6, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32375063

RESUMO

GGGGCC hexanucleotide repeat expansions (HREs) in C9orf72 cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) and lead to the production of aggregating dipeptide repeat proteins (DPRs) via repeat associated non-AUG (RAN) translation. Here, we show the similar intronic GGCCTG HREs that causes spinocerebellar ataxia type 36 (SCA36) is also translated into DPRs, including poly(GP) and poly(PR). We demonstrate that poly(GP) is more abundant in SCA36 compared to c9ALS/FTD patient tissue due to canonical AUG-mediated translation from intron-retained GGCCTG repeat RNAs. However, the frequency of the antisense RAN translation product poly(PR) is comparable between c9ALS/FTD and SCA36 patient samples. Interestingly, in SCA36 patient tissue, poly(GP) exists as a soluble species, and no TDP-43 pathology is present. We show that aggregate-prone chimeric DPR (cDPR) species underlie the divergent DPR pathology between c9ALS/FTD and SCA36. These findings reveal key differences in translation, solubility, and protein aggregation of DPRs between c9ALS/FTD and SCA36.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Dipeptídeos/genética , Demência Frontotemporal/genética , Proteínas Mutantes Quiméricas/genética , Ataxias Espinocerebelares/genética , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Elementos Antissenso (Genética)/genética , Expansão das Repetições de DNA , Feminino , Humanos , Íntrons/genética , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Sequências Repetitivas de Ácido Nucleico
10.
Gene ; 706: 19-31, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31028869

RESUMO

The fem-1 gene in Caenorhabditis elegans is involved in sex differentiation; it is specifically required for all aspects of male development. In this study, the full-length cDNA of the fem-1 (Pvfem-1) gene was isolated from the Pacific whiteleg shrimp Penaeus vannamei. The Pvfem-1 transcript is 3778 nt long and encodes a putative protein (PvFEM-1) of 638 amino acids that presented eight ankyrin repeats. The translated protein showed a significant (P < 0.05) structural similitude by superposition with C. elegans FEM-1 protein. Pvfem-1 expression was evaluated by qPCR and in situ hybridization (ISH) during embryogenesis, larval development, and gonads of both genders in subadult and adult life stages. Pvfem-1 was found expressed in brain, intestine, hepatopancreas, and in the gonads of both genders in subadults and adults when quantified by RT-qPCR. A significant finding was the discovery of a natural antisense transcript (NAT) of Pvfem-1 by ISH. It was present in the oocyte nucleus of subadult female shrimp gonads but was not seen within oocytes from adult females, although it was detected in follicular cells, suggesting a possible post-transcriptional regulation of Pvfem-1 in female gonad. Conversely, in males, no NAT was observed, and Pvfem-1 was found expressed in spermatogonia of both, subadult and adult shrimps indicating a function in male sexual differentiation and gametes generation. This study represents the first step for future functional analysis that is expected to contribute to clarifying the role of Pvfem-1 in sex differentiation and determination.


Assuntos
Elementos Antissenso (Genética)/fisiologia , Penaeidae/genética , Processos de Determinação Sexual/genética , Sequência de Aminoácidos , Animais , Elementos Antissenso (Genética)/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , DNA Complementar/metabolismo , Feminino , Regulação da Expressão Gênica/genética , Gônadas/metabolismo , Hibridização In Situ , Masculino , Ovário/metabolismo , Filogenia , RNA Mensageiro/genética , Alinhamento de Sequência , Análise de Sequência de DNA/métodos , Fatores Sexuais
11.
Mol Biol Rep ; 46(2): 2299-2305, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30756332

RESUMO

Natural antisense transcripts (NATs) have recently been associated with the development of human cancers. Recent studies have shown that a natural antisense transcript (NAT) is present in Sirt1 gene which encodes a NAD-dependent deacetylase. Interestingly, expression of Sirt1 mRNA changes during development and progression of human cancers. However, it remains unclear to what extent Sirt1 antisense transcript (AS) may contribute to changes in the expression of Sirt1 mRNA. To determine this, we used quantitative measurement of RNA to reveal relationship between Sirt1 mRNA and Sirt1-AS across human cancer tissues, cell lines and stem cells. While Sirt1 mRNA level was increased in cancer cell lines and cancer tissues, the expression level of Sirt1-AS was lower in cancers compared to controls. This inverse correlation was observed in the expression of Sirt1 sense and antisense transcripts in normal and cancer tissues suggesting a functional role for Sirt1-AS in regulation of Sirt1 mRNA.


Assuntos
Elementos Antissenso (Genética)/genética , Sirtuína 1/genética , Sirtuína 1/metabolismo , Animais , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , Neoplasias , RNA Antissenso/genética , RNA Mensageiro/genética
12.
Exp Dermatol ; 27(11): 1294-1297, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30076642

RESUMO

BACKGROUND: Drug-mediated disruption of IL17A, IL17F and IL17RA proteins is effective in psoriasis. However, disruption of the IL17 pathway by functional mutations has so far only been shown to affect risk in IL23R and TRAF3IP2. It is unclear whether this is due to rarity of disruptive mutations. OBJECTIVE: (a) To delineate the prevalence of mutations in key IL17 pathway genes and (b) to identify candidate regulatory sites acting on IL23R, IL17A, IL17RA and TRAF3IP2 from a distance. METHODS: Extraction of mutation frequencies from ExAc data, evolutionary sequence alignment; mapping of long-range interacting (LRI) enhancers; and genetic association testing in a novel psoriasis cohort. RESULTS: The prevalence of disruptive mutations in genes such as IL17RA is sufficient to have been detectable by existing data sets. Therefore, lack of their association with psoriasis indicates that genetic risk primarily resides in variants acting from a distance. We identify two LRI enhancer sites, regulating IL17RA and TRAF3IP2, respectively. The TRAF3IP2 regulator localizes to the TRAF3IP2 antisense promoter, suggesting feedback regulation. Both LRI sites are associated with psoriasis in a novel Scottish psoriasis cohort and the TRAF3IP2-LRI at rs71562294 replicates in the WTCCC cohort. CONCLUSION: Genetic risk for psoriasis may be encoded at LRI sites regulating IL17 pathway genes from a distance.


Assuntos
Regulação da Expressão Gênica/genética , Psoríase/genética , Receptores de Interleucina-17/genética , Transdução de Sinais/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Proteínas Adaptadoras de Transdução de Sinal , Elementos Antissenso (Genética)/genética , Estudos de Coortes , Feminino , Estudos de Associação Genética , Humanos , Interleucina-17/genética , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Receptores de Interleucina/genética
13.
Sci Rep ; 8(1): 3040, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445097

RESUMO

Age-related macular degeneration (AMD) predominantly affects the retina and retinal pigment epithelium in the posterior eye. While there are numerous studies investigating the non-coding transcriptome of retina and RPE, few significant differences between AMD and normal tissues have been reported. Strand specific RNA sequencing of both peripheral retina (PR) and RPE-Choroid-Sclera (PRCS), in both AMD and matched normal controls were generated. The transcriptome analysis reveals a highly significant and consistent impact on anti-sense transcription as well as moderate changes in the regulation of non-coding (sense) RNA. Hundreds of genes that do not express anti-sense transcripts in normal PR and PRCS demonstrate significant anti-sense expression in AMD in all patient samples. Several pathways are highly enriched in the upregulated anti-sense transcripts-in particular the EIF2 signaling pathway. These results call for a deeper exploration into anti-sense and noncoding RNA regulation in AMD and their potential as therapeutic targets.


Assuntos
Elementos Antissenso (Genética)/genética , Degeneração Macular/genética , Idoso , Idoso de 80 Anos ou mais , Elementos Antissenso (Genética)/fisiologia , Corioide/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Degeneração Macular/fisiopatologia , Masculino , Retina/metabolismo , Retina/fisiopatologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/fisiopatologia , Transcriptoma/genética
14.
Mol Cell Biochem ; 445(1-2): 59-65, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29247276

RESUMO

For patients with osteoporosis, the inability of osteogenic differentiation is the key reason for bone loss. In this study, we investigated the expression and function of long non-coding RNA BDNF-AS in mesenchymal stem cell-derived osteogenic differentiation. Mouse bone marrow-derived mesenchymal stem cells (BMMSCs) were cultured in vitro and induced toward osteogenic differentiation. Quantitative real-time PCR (qRT-PCR) was used to evaluate gene expressions of BDNF-AS and BDNF during osteogenic differentiation. BMMSCs were also extracted from ovariectomized (OVX) mice. The dynamic change of BDNF-AS in OVX-derived BMMSCs during osteogenic differentiation was also evaluated. Lentivirus was used to upregulate BDNF-AS in BMMSCs. The effects of BDNF-AS upregulation on BMMSCs' proliferation and osteogenic differentiation were then evaluated. In addition, qRT-PCR and western blot were applied to further examine the effect of BDNF-AS upregulation on osteogenesis-associated signaling pathways, including BDNF, OPN, and Runx2, in osteogenic differentiation. BDNF-AS was downregulated, whereas BDNF was upregulated in osteogenic differentiation of BMMSCs. Among OVX-derived BMMSCs, BDNF-AS expression was upregulated during osteogenic differentiation. Lentivirus-induced BDNF-AS upregulation promoted BMMSCs self-proliferation but inhibited osteogenic differentiation, as demonstrated by proliferation, alizarin red staining, and alkaline phosphatase activity assays, respectively. QRT-PCR and western blot demonstrated that BDNF, OPN, and Runx2 were downregulated by BDNF-AS upregulation in the differentiated BMMSCs. BDNF-AS is dynamically regulated in osteogenic differentiation. Upregulating BDNF-AS inhibits osteogenesis, possibly through inverse regulation on BDNF and osteogenic signaling pathways.


Assuntos
Elementos Antissenso (Genética)/genética , Células da Medula Óssea/citologia , Fator Neurotrófico Derivado do Encéfalo/genética , Diferenciação Celular/genética , Células-Tronco Mesenquimais/química , Osteogênese , RNA Longo não Codificante/fisiologia , Animais , Proliferação de Células , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Osteoporose/patologia , Ovariectomia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Regulação para Cima
15.
Biosystems ; 164: 199-216, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29107641

RESUMO

Sense and antisense peptides, i.e. peptides specified by complementary DNA and RNA sequences, interact with increased probability. Biro, Blalock, Mekler, Root-Bernstein and Siemion investigated the recognition rules of peptide-peptide interaction based on the complementary coding of DNA and RNA sequences in 3'→5' and 5'→3' directions. After more than three decades of theoretical and experimental investigations, the efficiency of this approach to predict peptide-peptide binding has been experimentally verified for more than 50 ligand-receptor systems, and represents a promising field of research. The natural genetic coding algorithm for sense and antisense peptide interactions combines following elements: of amino acid physico-chemical properties, stereochemical interaction, and bidirectional transcription. The interplay of these factors influences the specificity of sense-antisense peptide interactions, and affects the selection and evolution of peptide ligand-receptor systems. Complementary mRNA codon-tRNA anticodon complexes, and recently discovered Carter-Wolfenden tRNA acceptor-stem code, provide the basis for the rational modeling of peptide interactions based on their hydrophobic and lipophilic amino acid physico-chemical properties. It is shown that the interactions of complementary amino acid pairs according to the hydrophobic and lipophilic properties strongly depend on the central (second) purine base of the mRNA codon and its pyrimidine complement of the tRNA anticodon. This enables the development of new algorithms for the analysis of structure, function and evolution of protein and nucleotide sequences that take into account the residue's tendency to leave water and enter a nonpolar condensed phase considering its mass, size and accessible surface area. The practical applications of the sense-antisense peptide modeling are illustrated using different interaction assay types based on: microscale thermophoresis (MST), tryptophan fluorescence spectroscopy (TFS), nuclear magnetic resonance spectroscopy (NMR), and magnetic particles enzyme immunoassay (MPEIA). Various binding events and circumstances were considered, e.g., in situations with-short antisense peptide ligand (MST), L- and D-enantiomer acceptors (TFS), in low affinity conditions (NMR), and with more than one antisense peptide targeting hormone (MPEIA).


Assuntos
Algoritmos , Elementos Antissenso (Genética)/metabolismo , Código Genético/fisiologia , Peptídeos/metabolismo , Sequência de Aminoácidos/fisiologia , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Elementos Antissenso (Genética)/genética , Humanos , Peptídeos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Mol Genet Genomics ; 292(4): 833-846, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28357596

RESUMO

Alu elements in the human genome are present in more than one million copies, accounting for 10% of the genome. However, the biological functions of most Alu repeats are unknown. In this present study, we detected the effects of Alu elements on EGFP gene expression using a plasmid system to find the roles of Alu elements in human genome. We inserted 5'-4TMI-Alus-CMV promoter-4TMI-Alus (or antisense Alus)-3' sequences into the pEGFP-C1 vector to construct expression vectors. We altered the copy number of Alus, the orientation of the Alus, and the presence of an enhancer (4TMI) in the inserted 5'-4TMI-Alus-CMV promoter-4TMI-Alus (or antisense Alus)-3' sequences. These expression vectors were stably transfected into HeLa cells, and EGFP reporter gene expression was determined. Our results showed that combined sense-antisense Alu elements activated the EGFP reporter gene in the presence of enhancers and stable transfection. The combined sense-antisense Alu vectors carrying four copies of Alus downstream of inserted CMV induced much stronger EGFP gene expression than two copies. Alus downstream of inserted CMV were replaced to AluJBs (having 76% homology with Alu) to construct expression vectors. We found that combined sense-antisense Alu (or antisense AluJB) vectors induced strong EGFP gene expression after stable transfection and heat shock. To further explore combined sense-antisense Alus activating EGFP gene expression, we constructed Tet-on system vectors, mini-C1-Alu-sense-sense and mini-C1-Alu-sense-antisense (EGFP gene was driven by mini-CMV). We found that combined sense-antisense Alus activated EGFP gene in the presence of reverse tetracycline repressor (rTetR) and doxycycline (Dox). Clone experiments showed that Mini-C1-Alu-sense-antisense vector had more positive cells than that of Mini-C1-Alu-sense-sense vector. The results in this paper proved that Alu repetitive sequences inhibited gene expression and combined sense-antisense Alus activated EGFP reporter gene when Alu transcribes, which suggests that Alus play roles in maintaining gene expression (silencing genes or activating genes) in human genome.


Assuntos
Elementos Alu/genética , Elementos Antissenso (Genética)/genética , Regulação da Expressão Gênica/genética , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Sequências Reguladoras de Ácido Nucleico/genética , Linhagem Celular Tumoral , Dosagem de Genes/genética , Genoma Humano , Células HeLa , Humanos , Regiões Promotoras Genéticas , Ativação Transcricional/genética , Transfecção
17.
PLoS Genet ; 12(8): e1006224, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27487356

RESUMO

Antisense transcription is a prevalent feature at mammalian promoters. Previous studies have primarily focused on antisense transcription initiating upstream of genes. Here, we characterize promoter-proximal antisense transcription downstream of gene transcription starts sites in human breast cancer cells, investigating the genomic context of downstream antisense transcription. We find extensive correlations between antisense transcription and features associated with the chromatin environment at gene promoters. Antisense transcription downstream of promoters is widespread, with antisense transcription initiation observed within 2 kb of 28% of gene transcription start sites. Antisense transcription initiates between nucleosomes regularly positioned downstream of these promoters. The nucleosomes between gene and downstream antisense transcription start sites carry histone modifications associated with active promoters, such as H3K4me3 and H3K27ac. This region is bound by chromatin remodeling and histone modifying complexes including SWI/SNF subunits and HDACs, suggesting that antisense transcription or resulting RNA transcripts contribute to the creation and maintenance of a promoter-associated chromatin environment. Downstream antisense transcription overlays additional regulatory features, such as transcription factor binding, DNA accessibility, and the downstream edge of promoter-associated CpG islands. These features suggest an important role for antisense transcription in the regulation of gene expression and the maintenance of a promoter-associated chromatin environment.


Assuntos
Elementos Antissenso (Genética)/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Elementos Antissenso (Genética)/biossíntese , Cromatina/genética , Ilhas de CpG/genética , Regulação Fúngica da Expressão Gênica , Genômica , Código das Histonas/genética , Histonas/genética , Humanos , Proteínas Nucleares/biossíntese , Nucleossomos/genética , Ligação Proteica/genética , Alinhamento de Sequência
18.
Mol Cell Biol ; 36(6): 992-1006, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26755557

RESUMO

NuA4 histone lysine (K) acetyltransferase (KAT) promotes transcriptional initiation of TATA-binding protein (TBP)-associated factor (TAF)-dependent ribosomal protein genes. TAFs have also been recently found to enhance antisense transcription from the 3' end of the GAL10 coding sequence. However, it remains unknown whether, like sense transcription of the ribosomal protein genes, TAF-dependent antisense transcription of GAL10 also requires NuA4 KAT. Here, we show that NuA4 KAT associates with the GAL10 antisense transcription initiation site at the 3' end of the coding sequence. Such association of NuA4 KAT depends on the Reb1p-binding site that recruits Reb1p activator to the GAL10 antisense transcription initiation site. Targeted recruitment of NuA4 KAT to the GAL10 antisense transcription initiation site promotes GAL10 antisense transcription. Like NuA4 KAT, histone H3 K4/36 methyltransferases and histone H2B ubiquitin conjugase facilitate GAL10 antisense transcription, while the Swi/Snf and SAGA chromatin remodeling/modification factors are dispensable for antisense, but not sense, transcription of GAL10. Taken together, our results demonstrate for the first time the roles of NuA4 KAT and other chromatin regulatory factors in controlling antisense transcription, thus illuminating chromatin regulation of antisense transcription.


Assuntos
Elementos Antissenso (Genética)/genética , Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transativadores/genética , Elementos Antissenso (Genética)/metabolismo , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Transativadores/metabolismo , Sítio de Iniciação de Transcrição , Ativação Transcricional , Ubiquitinação
19.
Mol Pharm ; 12(12): 4509-17, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26559642

RESUMO

Glioblastoma (GBM) generally exhibits high IC50 values for its standard drug treatment, temozolomide (TMZ). MicroRNA-21 (miR-21) is an oncomiR overexpressed in GBM, thus controlling important aspects of glioma biology. We hypothesized that PLGA nanoparticles carrying antisense miR-21 to glioblastoma cells might beneficially knock down endogenous miR-21 prior to TMZ treatment. PLGA nanoparticles encapsulating antisense miR-21 were effective in intracellular delivery and sustained silencing (p < 0.01) of miR-21 function in U87 MG, LN229, and T98G cells. Prior antisense miR-21 delivery significantly reduced the number of viable cells (p < 0.001), and increased (1.6-fold) cell cycle arrest at G2/M phase upon TMZ treatment in U87 MG cells. There was overexpression of the miR-21 target genes PTEN (by 67%) and caspase-3 (by 15%) upon cotreatment. This promising PLGA nanoparticle-based platform for antisense miR-21 delivery to GBM is an effective cotherapeutic strategy in cell culture, warranting the need for further studies prior to future clinical translation.


Assuntos
Elementos Antissenso (Genética)/genética , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , MicroRNAs/genética , Nanopartículas/administração & dosagem , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Caspase 3/genética , Linhagem Celular Tumoral , Dacarbazina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioma/tratamento farmacológico , Glioma/genética , Humanos , PTEN Fosfo-Hidrolase/genética , Temozolomida
20.
Mol Ther ; 23(12): 1810-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26216517

RESUMO

Heart failure (HF) is the end result of a diverse set of causes such as genetic cardiomyopathies, coronary artery disease, and hypertension and represents the primary cause of hospitalization in Europe. This serious clinical disorder is mostly associated with pathological remodeling of the myocardium, pump failure, and sudden death. While the survival of HF patients can be prolonged with conventional pharmacological therapies, the prognosis remains poor. New therapeutic modalities are thus needed that will target the underlying causes and not only the symptoms of the disease. Under chronic cardiac stress, small noncoding RNAs, in particular microRNAs, act as critical regulators of cardiac tissue remodeling and represent a new class of therapeutic targets in patients suffering from HF. Here, we focus on the potential use of microRNA inhibitors as a new treatment paradigm for HF.


Assuntos
Elementos Antissenso (Genética)/uso terapêutico , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , MicroRNAs/uso terapêutico , Animais , Elementos Antissenso (Genética)/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Insuficiência Cardíaca/terapia , Humanos , MicroRNAs/genética , Miocárdio/patologia
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