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1.
J Gastroenterol ; 58(9): 894-907, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37227481

RESUMO

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is an advanced form of chronic fatty liver disease, which is a driver of hepatocellular carcinoma. However, the roles of the C5aR1 in the NASH remain poorly understood. Here, we aimed to investigate the functions and mechanisms of the C5aR1 on hepatic inflammation and fibrosis in murine NASH model. METHODS: Mice were fed a normal chow diet with corn oil (ND + Oil), a Western diet with corn oil (WD + Oil) or a Western diet with carbon tetrachloride (WD + CCl4) for 12 weeks. The effects of the C5a-C5aR1 axis on the progression of NASH were analyzed and the underlying mechanisms were explored. RESULTS: Complement factor C5a was elevated in NASH mice. C5 deficiency reduced hepatic lipid droplet accumulation in the NASH mice. The hepatic expression levels of TNFα, IL-1ß and F4/80 were decreased in C5-deficient mice. C5 loss alleviated hepatic fibrosis and downregulated the expression levels of α-SMA and TGFß1. C5aR1 deletion reduced inflammation and fibrosis in NASH mice. Transcriptional profiling of liver tissues and KEGG pathway analysis revealed that several pathways such as Toll-like receptor signaling, NFκB signaling, TNF signaling, and NOD-like receptor signaling pathway were enriched between C5aR1 deficiency and wild-type mice. Mechanistically, C5aR1 deletion decreased the expression of TLR4 and NLRP3, subsequently regulating macrophage polarization. Moreover, C5aR1 antagonist PMX-53 treatment mitigated the progression of NASH in mice. CONCLUSIONS: Blockade of the C5a-C5aR1 axis reduces hepatic steatosis, inflammation, and fibrosis in NASH mice. Our data suggest that C5aR1 may be a potential target for drug development and therapeutic intervention of NASH.


Assuntos
Hepatite , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Receptor 4 Toll-Like/metabolismo , Óleo de Milho/metabolismo , Óleo de Milho/uso terapêutico , Camundongos Knockout , Fígado/patologia , Fibrose , Cirrose Hepática/patologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/patologia , Transdução de Sinais , Neoplasias Hepáticas/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL
2.
Am J Transplant ; 23(4): 484-497, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36746335

RESUMO

Brain death (BD) donors are the primary source of donor organs for liver transplantation. However, the effects of BD on donor livers and outcomes after liver transplantation remain unclear. Here, we explored the role of complement and the therapeutic effect of complement inhibition in BD-induced liver injury and posttransplantation injury in a mouse BD and liver transplantation model. For complement inhibition, we used complement receptor 2 (CR2)-Crry, a murine inhibitor of C3 activation that specifically targets sites of complement activation. In the mouse model, BD resulted in complement activation and liver injury in donor livers and a cascade liver injury posttransplantation, mediated in part through the C3a-C3aR (C3a receptor) signaling pathway, which was ameliorated by treatment with CR2-Crry. Treatment of BD donors with CR2-Crry improved graft survival, which was further improved when recipients received an additional dose of CR2-Crry posttransplantation. Mechanistically, we determined that complement inhibition alleviated BD-induced donor liver injury and posttransplant cascade injury by regulating phosphoinositide 3-kinase (PI3K) signaling pathways. Together, BD induced donor liver injury and cascade injury post-transplantation, which was mediated by complement activation products acting on PI3K signaling pathways. Our study provides an experimental basis for developing strategies to improve the survival of BD donor grafts in liver transplantation.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Transplante de Fígado , Traumatismo por Reperfusão , Animais , Camundongos , Humanos , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinase , Transplante de Fígado/efeitos adversos , Morte Encefálica , Doadores Vivos , Proteínas do Sistema Complemento , Transdução de Sinais , Proteínas Recombinantes de Fusão
3.
Am J Transl Res ; 13(8): 8766-8776, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539993

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies across nations. Although the outcome of HCC has been improved significantly with the advances in comprehensive treatment, patients remain suffered from recurrence as well as metastasis. Therefore, it is urgent to identify reliable biomarkers for predicting the recurrence of HCC, by which the treating strategy can be made to restrain tumor progress. Increasing evidence has shown the association between immune signature and prognosis of HCC. Thus, we aimed to discover an immune-related gene signature that can estimate the recurrence rates of HCC. We collected gene expression profiles and clinical information of patients from GEO and TCGA dataset. Furthermore, we conducted a lasso regression analysis and established a recurrence-related model consisting of 36 immune-related gene pairs (IRGPs) with 54 genes. We validated the IRGPs in the validation cohort and observed that the immune-related signature robustly stratified patients with HCC into high- and low-risk groups in terms of recurrence (P < 0.001). Multivariant Cox regression analysis showed the relationship between the model and recurrence outcomes (Hazard Ratio: 3.81 95% Confidence Interval: 2.90-5.00). Gene Ontology and KEGG enrichment analyses revealed that those genes were enriched in important signaling pathways. In summary, we developed a robust model based on the signature of immune-related genes for forecasting the recurrence outcome of patients with HCC, which holds the potential to assist clinical practice.

4.
Biochem Cell Biol ; 98(3): 327-337, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32383631

RESUMO

BACKGROUND: Imbalanced immune response and hepatic fibrosis are key factors related to the progression of chronic liver diseases. Tetramethylpyrazine (TMP), a natural alkaloid, has been widely used for treating liver injury. In this study, we explored the effect of TMP on hepatic fibrosis and the related mechanisms regulating autophagy. METHODS: A rat model of hepatic fibrosis and a model using an hepatic stellate cell line (HSC-T6) were created using CCl4 and platelet-derived growth factor (PDGF). Staining with haematoxylin and eosin (HE), Masson's stain, and TUNEL were performed for pathological diagnosis. ELISA, Western blotting, and immunofluorescence analyses were conducted to determine the expression levels of the specific markers for fibrosis, autophagy, inflammation, and signalling pathways. RESULTS: TMP treatment significantly rescued pathological injury and hepatic fibrosis. It also alleviated imbalances in the immune system, accumulation of extracellular matrix, and autophagy signals in hepatic fibrosis. At the same time, we found that application of the autophagy inducer rapamycin enhanced the therapeutic effect of TMP, whereas the autophagy inhibitor 3-methyladenine, PI3K pathway inhibitor LY294002, and AKT pathway agonist SC79 did the opposite. CONCLUSIONS: TMP exerts therapeutic effects in hepatic fibrosis mainly through promoting autophagy to ameliorate inflammation by inhibiting the AKT-mTOR signalling pathway, providing a new perspective for the treatment of chronic liver diseases.


Assuntos
Autofagia , Fibrinolíticos/uso terapêutico , Células Estreladas do Fígado/metabolismo , Inflamação/metabolismo , Cirrose Hepática/tratamento farmacológico , Pirazinas/uso terapêutico , Animais , Tetracloreto de Carbono , Linhagem Celular Tumoral , Cromonas/farmacologia , Doença Crônica , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/metabolismo , Masculino , Microscopia de Fluorescência , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Derivado de Plaquetas , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
5.
Biomed Pharmacother ; 125: 110029, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32106378

RESUMO

Faciogenital Dysplasia 1 (FGD1) has been involved in a variety of biological processes, including cytoskeleton restructuring, cell morphology, cell cycle progression, and cell polarity. Abnormal expression of FGD1 was also identified in several types of cancers, indicating its critical role in the development of cancers. However, little is known about the role of FGD1 in hepatocellular carcinoma (HCC). In this study, the expression of FGD1 in HCC was mined with the RNA sequencing data from the cancer genome atlas. By over-expressing or knocking down of FGD1, the effects of FGD1 on the malignant behavior of HCC were evaluated both in vitro and in vivo. We find that FGD1 is up-regulated in HCC and correlated with the development and prognosis of HCC. By over-expressing or knocking down of FGD1, the effects of FGD1 on the malignant behavior of HCC were evaluated both in vitro and in vivo. Knockdown of FGD1 remarkably inhibits the malignant behaviors and causes morphological disorder of pseudopodia, autophagy inhibition and mitochondrial dyfunction in HCC cells. Further investigation shows that Cdc42, a Rho GTPase, plays a role in these processes. Overexpression of FGD1 significantly promotes the oncogenic properties of HCC cells. Collectively, these findings reveal that FGD1 exhibits oncogenic properties in HCC through regulating cell morphology, autophagy and mitochondrial function, suggesting that FGD1 may serve as a potential therapeutic target for HCC.


Assuntos
Autofagia/genética , Carcinoma Hepatocelular/etiologia , Fatores de Troca do Nucleotídeo Guanina/genética , Neoplasias Hepáticas/etiologia , Mitocôndrias/genética , Oncogenes , Adulto , Idoso , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Xenoenxertos , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Gradação de Tumores , Estadiamento de Neoplasias
6.
Biomed Pharmacother ; 124: 109857, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31972358

RESUMO

TRAF-interacting protein (TRAIP) is a RING-type E3 ubiquitin ligase which has been implicated in various cellular processes, including NF-κB activation, DNA damage response, mitosis, and tumorigenesis. It is considered as a tumor suppressor in basal cell carcinomas and breast cancer in previous studies. However, in our current study, we found that TRAIP exhibited oncogenic properties in liver cancer. In order to determine its effect on tumor biology and the potential mechanism, a variety of advanced experimental technology was used, such as bioinformatic analysis, isobaric tags for relative and absolute quantification (iTRAQ) analysis, tissue microarray detection, and other in vitro cell biology experiments. The results showed that TRAIP was up-regulated in liver cancer and negatively correlated with prognosis. When TRAIP was knocked-down with lentivirus containing specific targeting short hairpin RNAs, the malignant behaviors of Bel7404 cells were significantly inhibited. Meanwhile, overexpression of TRAIP exerted oncogenic effects in SNU449 cells. More importantly, the iTRAQ analysis indicated that TRAIP was significantly related to centriole, centromere, and histone deacetylation, which are critical for mitosis. These findings are in line with previous reports that TRAIP contributes to proper mitosis. Additionally, the iTRAQ analysis also supported that TRAIP may affect G1/S transition by regulating the expression of certain cell cycle related proteins. In summary, our study firstly revealed that TRAIP was up-regulated and negatively correlated with prognosis in liver cancer patients and exhibited oncogenic properties in liver cancer cells, making it a potential target for treatment of liver cancer.


Assuntos
Neoplasias Hepáticas/patologia , Ubiquitina-Proteína Ligases/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Regulação para Cima
7.
Cell Res ; 29(7): 548-561, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31076642

RESUMO

Complement is known to play a role in alcoholic fatty liver disease (AFLD), but the underlying mechanisms are poorly understood, thereby constraining the development of a rational approach for therapeutic intervention in the complement system. C3 deficiency has been shown to impart protective effects against ethanol-induced hepatic steatosis and inflammation. Here we demonstrate a protection effect in wild-type mice by treatment with CR2-Crry, a specific inhibitor of C3 activation. The expression of glycine transfer (t) RNA-derived fragments (Gly-tRFs) is upregulated in ethanol-fed mice and inhibition of Gly-tRFs in vivo decreases chronic ethanol feeding-induced hepatosteatosis without affecting inflammation. The expression of Gly-tRF was downregulated in C3-deficient or CR2-Crry-treated mice, but not in C5-deficient mice; Gly-tRF expression was restored by the C3 activation products C3a or Asp (C3a-des-Arg) via the regulation of CYP2E1. Transcriptome profiling of hepatic tissues showed that Gly-tRF inhibitors upregulate the expression of sirtuin1 (Sirt1) and subsequently affect downstream lipogenesis and ß-oxidation pathways. Mechanistically, Gly-tRF interacts with AGO3 to downregulate Sirt1 expression via sequence complementarity in the 3' UTR. Notably, the expression levels of C3d, CYP2E1 and Gly-tRF are upregulated, whereas Sirt1 is decreased in AFLD patients compared to healthy controls. Collectively, our findings suggest that C3 activation products contribute to hepatosteatosis by regulating the expression of Gly-tRF. Complement inhibition at the C3 activation step and treatment with Gly-tRF inhibitors may be potential and precise therapeutic approaches for AFLD.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Complemento C3/antagonistas & inibidores , Complemento C3/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Fígado/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Animais , Linhagem Celular , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado Gorduroso Alcoólico/tratamento farmacológico , Humanos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
8.
World J Gastroenterol ; 25(48): 6902-6915, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31908394

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignant gastrointestinal tumor. There are currently few clinical diagnostic and prognostic markers for HCC. LncRNA cancer susceptibility candidate 9 (CASC9) is a long-chain non-coding RNA discovered in recent years, and previous studies have found that lncRNA CASC9 participates in the occurrence and development of HCC, but its clinical value remains unclear. AIM: To determine the expression of lncRNA CASC9 in HCC and its diagnostic and prognostic value. METHODS: Data on CASC9 expression in patients with HCC were collected from the Cancer Genome Atlas (TCGA) database to analyze the relationship between CASC9 and patient survival. A total of 80 HCC patients treated in The First Affiliated Hospital of Guangxi Medical University from May 2012 to January 2014 were enrolled in the patient group, and 50 healthy subjects were enrolled in the control group during the same period. CASC9 expression in the two groups was determined using quantitative real-time polymerase chain reaction, and its diagnostic and prognostic value was analyzed based on the CASC9 data and pathological data in these HCC patients. The relationship between CASC9 and patient survival was assessed during the 5-year follow-up period. RESULTS: Analysis of data from TCGA database revealed that control samples showed significantly lower CASC9 expression than carcinoma tissue samples (P < 0.001); the low CASC9 expression group had a higher survival rate than the high CASC9 expression group (P = 0.011), and the patient group showed significantly increased expression of serum CASC9, with the area under the curve (AUC) of 0.933. CASC9 expression was related to tumor size, combined hepatitis, tumor, node, metastasis (TNM) staging, lymph node metastasis, differentiation and alpha fetoprotein, and the high CASC9 expression group showed lower 1-year, 3-year and 5-year survival rates than the low CASC9 expression group (all a P < 0.05). Multivariate Cox regression analysis revealed that TNM staging, lymph node metastasis, differentiation, alpha fetoprotein and CASC9 were independent factors affecting the prognosis of patients. Stage I+II patients with lymph node metastasis, low differentiation, and alpha fetoprotein > 200 ng/mL had a poor 5-year survival rate. CONCLUSION: High CASC9 expression is beneficial in the prognosis of HCC patients. CASC9 is expected to be a potential diagnostic and prognostic indicator of HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , RNA Longo não Codificante/metabolismo , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Estudos de Casos e Controles , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Voluntários Saudáveis , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , RNA Longo não Codificante/sangue , Curva ROC , Taxa de Sobrevida
9.
J Drug Target ; 27(7): 797-805, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30481072

RESUMO

Pancreatic cancer is one of the deadliest cancers across the world with an average 5-year survival rate of less than <6%. In this study, gemcitabine (GEM) and HIF1α-siRNA loaded GE-11 peptide conjugated liposome was successfully prepared and evaluated for its antitumor efficacy in pancreatic cancer cells. The GE11 increased the targeting specificity of liposome carrier and increased the intracellular concentrations in the cancer cells. Furthermore, synergistic combination of GEM and HIF1a-siRNA exhibited remarkable improvement in the declining of cancer cell proliferations. siRNA could effectively decrease the expression of HIF1a gene in the cancer cells. Importantly, GE-11 peptide-conjugated GEM/siRNA-loaded liposomes (GE-GML/siRNA) increased the total amount of apoptosis cells with higher proportion of cells in late apoptosis phase. GE-GML induced remarkable apoptosis of cancer cells and induced chromatin condensation and nuclear fragmentation which are considered to be typical features of apoptosis and cell death. GE-GML/siRNA showed a significant reduction in the tumour burden suggesting the superior anticancer efficacy of this formulation. GE-GML/siRNA showed four-fold reduction in tumour compared to control and two-fold reduction compared to GE-GML, respectively. Overall, present work lays foundation for the combination of GEM and HIF1a-siRNA loaded in a targeted nanocarrier system as a unique therapeutic option in pancreatic cancer treatment.


Assuntos
Anticorpos/uso terapêutico , Desoxicitidina/análogos & derivados , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Neoplasias Pancreáticas/tratamento farmacológico , Peptídeos/síntese química , RNA Interferente Pequeno/química , Animais , Anexina A5/genética , Anexina A5/metabolismo , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Camundongos , Camundongos Nus , Nanoestruturas , Neoplasias Experimentais/tratamento farmacológico , Gencitabina
10.
Chem Biol Interact ; 291: 65-71, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29859832

RESUMO

Pancreatic cancer is one of deadly cancers and is responsible for significant mortality and morbidity across the globe. The unavailability of the efficient chemotheruptic drugs and the potent thereuprtic targets forms a bottleneck in the treatment of pancreatic cancer. In this study we explored the potential of MicroRNA-1179 as the therapeutic target for the treatment of pancreatic cancer. The results of this study indicated that the expression of miR-1179 was significantly downregulated in the pancreatic cancer cell lines as compared to the normal pancreatic cells. To unveil the potential role of miR-1179, it was overexpressed in the pancreatic cancer cells. It was observed that ectopic expression of miR-1179 caused reduction in the proliferation of pancreatic cancer cells by triggering G0/G1 cell cycle arrest. Further, overexpression of miR-1179 caused inhibition of the cell migration and invasion of the pancreatic cancer cells. To find out the potential target of miR-1179 in pancreatic cancer cells, we carried out bioinformatic analysis, the results showed that miR-1179 targets E2F transcription factor 5. This was also confirmed by western blotting analysis wherein in overexpression of miR-1179 was associated with the downregulation of the expression E2F5. Conversely, silencing of E2F5 had similar effects as that of miR-1179 suppression. Further, E2F5 overexpression could also nullify the effect on cell proliferation, migration and invasion in pancreatic cancer cells. Finally, miR-1179 overexpression could also inhibit tumor growth in vivo by suppressing the expression of E2F5. Taken together, we conclude that miR-1179 overexpression may prove beneficial for the treatment of pancreatic cancer.


Assuntos
Movimento Celular , Fator de Transcrição E2F5/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica
11.
J Ind Microbiol Biotechnol ; 42(8): 1183-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26047996

RESUMO

Cordyceps militaris is an important medicinal fungus. Commercialization of this fungus needs to improve the fruiting body production by molecular engineering. An improved Agrobacterium tumefaciens-mediated transformation (ATMT) method was used to select an insertional mutant (g38) which exhibited fast stromatal differentiation and increased yield. The Rhf1 gene encoding filamentation protein was destroyed by a single T-DNA and no Rhf1 transcription was detected in mutant g38. To verify the function of the Rhf1 gene, RNA interference plasmid and overexpression vector of the Rhf1 gene were constructed and transferred to the wild-type JM4 by ATMT. Fast stromatal differentiation and larger fruiting bodies were found in the RNAi-Rhf1 mutants (JM-iRhf1). In the overexpression mutants (JM-OERhf1), neither stromata nor fruiting bodies appeared. The rescued strain (38-OERhf1) showed similar growth characteristics as JM4. These results indicated that the Rhf1 gene was involved in the stromatal differentiation and the shape formation of fruiting bodies.


Assuntos
Cordyceps/genética , Carpóforos/crescimento & desenvolvimento , Genes Fúngicos , Agrobacterium tumefaciens/genética , Cordyceps/crescimento & desenvolvimento , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Carpóforos/genética , Vetores Genéticos , Mutagênese Insercional , Plasmídeos/genética , Interferência de RNA
12.
World J Microbiol Biotechnol ; 28(1): 371-80, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22806813

RESUMO

The full-length cytochrome c oxidase subunit I gene (cox1) containing a group I intron was isolated from an important medical fungus Cordyceps militaris (Cordycipitaceae). The open reading frame (ORF) of 1,593 nucleotides encoded a predicted protein COX1 of 530 amino acids. The group I intron encoded a putative homing endonuclease (HE) with two LAGLIDADG motifs. RT-PCR and Northern analysis showed a mature transcript of spliced cox1. Both 5'exon-intron and intron-3'exon junctions were also found by RT-PCR, suggesting the possible presence of unspliced cox1 RNA in total RNA. Sequence comparison by BLASTn showed that the coding region of cox1 (CRcox1) of C. militaris had significant similarities to those of related species (such as Cordyceps bassiana and C. brongniartii), while the intron had no significant homologous sequences of Cordycipitaceae fungi in NCBI database. The phylogenetic tree based on the CRcox1 confirmed the present taxonomic status of related species, but the cox1 introns were phylogenetically distinct. Compared to C. bassiana and C. brongniartii, the cox1 intron of C. militaris exhibited specific splicing site and different intronic ORF. The analysis of the folding RNA structures of the known cox1 introns from Cordyceps species showed different base pairs and conserved regions (P1-P10) in their structures. The present results provide useful information on the studies of cox1 intron splicing and Cordyceps evolution.


Assuntos
Cordyceps/enzimologia , Cordyceps/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Endonucleases/genética , Proteínas Fúngicas/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Sequência de Bases , DNA Fúngico/genética , Endonucleases/química , Éxons , Proteínas Fúngicas/química , Genes Fúngicos , Íntrons , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Splicing de RNA , RNA Fúngico/química , RNA Fúngico/genética , Especificidade da Espécie , Transcrição Gênica
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