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1.
Nature ; 625(7995): 593-602, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093017

RESUMO

Emerging data have shown that previously defined noncoding genomes might encode peptides that bind human leukocyte antigen (HLA) as cryptic antigens to stimulate adaptive immunity1,2. However, the significance and mechanisms of action of cryptic antigens in anti-tumour immunity remain unclear. Here mass spectrometry of the HLA class I (HLA-I) peptidome coupled with ribosome sequencing of human breast cancer samples identified HLA-I-binding cryptic antigenic peptides that were noncanonically translated by a tumour-specific circular RNA (circRNA): circFAM53B. The cryptic peptides efficiently primed naive CD4+ and CD8+ T cells in an antigen-specific manner and induced anti-tumour immunity. Clinically, the expression of circFAM53B and its encoded peptides was associated with substantial infiltration of antigen-specific CD8+ T cells and better survival in patients with breast cancer and patients with melanoma. Mechanistically, circFAM53B-encoded peptides had strong binding affinity to both HLA-I and HLA-II molecules. In vivo, administration of vaccines consisting of tumour-specific circRNA or its encoded peptides in mice bearing breast cancer tumours or melanoma induced enhanced infiltration of tumour-antigen-specific cytotoxic T cells, which led to effective tumour control. Overall, our findings reveal that noncanonical translation of circRNAs can drive efficient anti-tumour immunity, which suggests that vaccination exploiting tumour-specific circRNAs may serve as an immunotherapeutic strategy against malignant tumours.


Assuntos
Neoplasias da Mama , Melanoma , Peptídeos , Biossíntese de Proteínas , RNA Circular , Animais , Feminino , Humanos , Camundongos , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Espectrometria de Massas , Melanoma/genética , Melanoma/imunologia , Melanoma/mortalidade , Melanoma/patologia , Peptídeos/genética , Peptídeos/imunologia , Perfil de Ribossomos , RNA Circular/genética , RNA Circular/metabolismo , Análise de Sobrevida
2.
Mol Cell ; 81(8): 1781-1788.e4, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33571424

RESUMO

Mediator is a universal adaptor for transcription control. It serves as an interface between gene-specific activator or repressor proteins and the general RNA polymerase II (pol II) transcription machinery. Previous structural studies revealed a relatively small part of Mediator and none of the gene activator-binding regions. We have determined the cryo-EM structure of the Mediator at near-atomic resolution. The structure reveals almost all amino acid residues in ordered regions, including the major targets of activator proteins, the Tail module, and the Med1 subunit of the Middle module. Comparison of Mediator structures with and without pol II reveals conformational changes that propagate across the entire Mediator, from Head to Tail, coupling activator- and pol II-interacting regions.


Assuntos
Subunidade 1 do Complexo Mediador/metabolismo , Aminoácidos/genética , Conformação Proteica , RNA Polimerase II/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética
3.
Metab Brain Dis ; 39(4): 569-576, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38300392

RESUMO

Glioblastoma (GBM) is a common primary central nervous system tumor. Although the multimodal integrated treatment for GBM has made great progress in recent years, the overall survival time of GBM is still short. Thus, novel treatments for GBM are worth further investigation and exploration. This study aimed to investigate the effects of etomidate on GBM tumor growth and the underlying mechanism. A xenograft tumor model was established and treated with etomidate to assess tumor growth. Immunohistochemistry (IHC) assay evaluated the positive rate of Ki67 cells in tumor tissues. Cell counting kit (CCK)-8 and EdU assays accessed the cell viability and proliferation. Immunofluorescence (IF) staining detected the distribution of macrophage markers in tumor tissues. The percentages of M1- and M2-like macrophages in tumor-associated macrophages (TAMs) and co-culture system (macrophages and GBM cells) were detected using flow cytometry. Macrophage polarization-related genes were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Etomidate treatment inhibited the tumor growth, and increased the CD86+ cells but decreased the CD206+ cells in TAMs. The gene expression of M1 markers was increased in TAMs of etomidate-treated mice, whereas that of M2 markers was decreased. Moreover, etomidate treatment increased the number of CD86+ M1-like macrophages co-cultured with tumor cells but decreased that of CD206+ M2-like macrophages, with the upregulation of M1 markers and downregulation of M2 markers. Etomidate inhibited GBM tumor growth by promoting M1 macrophage polarization, suggesting a new insight into the clinical treatment of GBM.


Assuntos
Neoplasias Encefálicas , Etomidato , Glioblastoma , Macrófagos , Etomidato/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Animais , Camundongos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo , Camundongos Nus
4.
Artigo em Inglês | MEDLINE | ID: mdl-38536574

RESUMO

While the correlation between parental autonomy granting and adolescents' problematic Internet use (PIU) has been confirmed, the processes underlying this connection have not been thoroughly investigated. Drawing on the ecological systems theory, this study sought to investigate the mediating mechanism of peer attachment and the moderating mechanism of school climate that link parental autonomy granting to PIU. A two-wave longitudinal design was employed with a time interval of six months. The participants were 852 adolescents who attended three middle schools located in Guangdong Province, China. Self-report questionnaires were used to obtain data on demographics, parental autonomy granting, peer attachment, school climate, and PIU. The findings indicated that peer attachment significantly mediated the link between parental autonomy granting and adolescent PIU. A positive school climate significantly moderated the influence of parental autonomy granting on peer attachment and the influence of peer attachment on PIU. Specifically, the association between parental autonomy granting and peer attachment and the association between peer attachment and PIU were more pronounced when the school climate was perceived to be positive. This research underscores the possible significance of peer attachment in the association between parental autonomy granting and PIU and offers valuable insights for mitigating the negative outcomes of PIU.

5.
Angew Chem Int Ed Engl ; 63(7): e202317987, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38152839

RESUMO

Platinum metal (PtM, M=Ni, Fe, Co) alloys catalysts show high oxygen reduction reaction (ORR) activity due to their well-known strain and ligand effects. However, these PtM alloys usually suffer from a deficient ORR durability in acidic environment as the alloyed metal is prone to be dissolved due to its high electronegativity. Herein, we report a new class of PtMn alloy nanodendrite catalyst with low-electronegativity Mn-contraction for boosting the oxygen reduction durability of fuel cells. The moderate strain in PtMn, induced by Mn contraction, yields optimal oxygen reduction activity at 0.53 A mg-1 at 0.9 V versus reversible hydrogen electrode (RHE). Most importantly, we show that relative to well-known high-electronegativity Ni-based Pt alloy counterpart, the PtMn nanodendrite catalyst experiences less transition metals' dissolution in acidic solution and achieves an outstanding mass activity retention of 96 % after 10,000 degradation cycles. Density functional theory calculation reveals that PtMn alloys are thermodynamically more stable than PtNi alloys in terms of formation enthalpy and cohesive energy. The PtMn nanodendrite-based membrane electrode assembly delivers an outstanding peak power density of 1.36 W cm-2 at a low Pt loading and high-performance retention over 50 h operations at 0.6 V in H2 -O2 hydrogen fuel cells.

6.
Nucleic Acids Res ; 49(20): 11900-11919, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34669960

RESUMO

Post-transcriptional modifications affect tRNA biology and are closely associated with human diseases. However, progress on the functional analysis of tRNA modifications in metazoans has been slow because of the difficulty in identifying modifying enzymes. For example, the biogenesis and function of the prevalent N2-methylguanosine (m2G) at the sixth position of tRNAs in eukaryotes has long remained enigmatic. Herein, using a reverse genetics approach coupled with RNA-mass spectrometry, we identified that THUMP domain-containing protein 3 (THUMPD3) is responsible for tRNA: m2G6 formation in human cells. However, THUMPD3 alone could not modify tRNAs. Instead, multifunctional methyltransferase subunit TRM112-like protein (TRMT112) interacts with THUMPD3 to activate its methyltransferase activity. In the in vitro enzymatic assay system, THUMPD3-TRMT112 could methylate all the 26 tested G6-containing human cytoplasmic tRNAs by recognizing the characteristic 3'-CCA of mature tRNAs. We also showed that m2G7 of tRNATrp was introduced by THUMPD3-TRMT112. Furthermore, THUMPD3 is widely expressed in mouse tissues, with an extremely high level in the testis. THUMPD3-knockout cells exhibited impaired global protein synthesis and reduced growth. Our data highlight the significance of the tRNA: m2G6/7 modification and pave a way for further studies of the role of m2G in sperm tRNA derived fragments.


Assuntos
Metiltransferases/metabolismo , RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/metabolismo , tRNA Metiltransferases/metabolismo , Células HEK293 , Células HeLa , Humanos , Metilação , Metiltransferases/genética , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/genética , Especificidade por Substrato , tRNA Metiltransferases/genética
7.
Plant Dis ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157103

RESUMO

Soil-borne plant-pathogenic Phytopythium spp. can cause root rot and damping off on important plant species, resulting in serious economic loss. A survey in October 2021 identified soil-borne diseases occurring on Macadamia integrifolia in Yunnan Province, China. Microbes were isolated from necrotic roots of 23 trees with root rot symptoms by growing on cornmeal-based oomycete-selective 3P (Haas 1964) and P5APR (Jeffers and Martin, 1986) media at 24ºC in the dark for 7 days. Of the 56 single-hyphal isolates obtained, 18 were morphologically similar to Phytopythium vexans (van der Plaats-Niterink 1981; de Cock et al. 2015). Isolates LC04 and LC051 were selected for molecular analyses. The internal transcribed spacer (ITS) region and the cytochrome c oxidase subunit II (CoxII) gene were PCR-amplified using universal primers ITS1/ITS4 (White et al. 1990) and oomycete-specific primers Cox2-F/Cox2-RC4 (Choi et al. 2015), respectively. The PCR products were sequenced with the amplification primers and sequences were lodged in Genbank (Accession no. OM346742, OM415989 for ITS, OM453644, OM453643 for CoxII for isolates LC04 and LC051, respectively). The top BLAST hit in the Genbank nr database for all four sequences was Phytopythium vexans (>99% identity). A maximum-likelihood phylogenetic tree was constructed with analogous concatenated ITS and CoxII sequences from either type or voucher specimens of 13 Phytopythium species in the same phylogenetic clade as P. vexans (Table 1; Bala et. al 2010). Isolates LC04 and LC051 grouped most closely to P. vexans, with LC051 basal and sister to LC04 and P. vexans voucher specimen CBS119.80 with 100% support (Fig. 1). Millet seed inoculated with agar pieces colonized by P. vexans LC04 and LC51 was used to fulfill Koch's postulates (Li et al. 2015) in a completely randomized experimental design. Four 6-month-old M. integrifolia var. Keaau (660) seedlings were transplanted into pasteurized commercial potting mix containing 0.5% (w/w) inoculum. Plants were grown in free draining pots and watered once a day. At 14 days post-inoculation, roots were discolored compared to control plants inoculated with millet seed mixed with agar plugs lacking P. vexans (Fig. 2). By 30 days post-inoculation, infected roots were discolored with obvious decay and reduction in root system size. Control plants were symptomless. P. vexans was successfully re-isolated from two lesioned roots from each plant. The infection experiment was done twice, demonstrating that P. vexans LC04 and LC51 caused root disease on M. integrifolia. P. vexans causes root rot, damping-off, crown rot, stem rot or patch canker on economically important trees in many parts of the world, including seven plant species in China (Farr and Rossman 2022). This is the first report of pathogenic P. vexans on M. integrifolia in China. Reports of pathogenic P. vexans on multiple hosts in several parts of the world suggest it should be considered a quarantine risk and included in risk mitigation or pest management plans that include other species of Phytopythium, or species of Pythium or Phytophthora, to which P. vexans has many similarities (de Cock et al. 2015).

8.
Biochem Biophys Res Commun ; 606: 23-28, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-35338855

RESUMO

Coronavirus disease 2019 (COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly emerging infectious disease currently spreading across the world. The spike (S) protein plays a key role in the receptor recognition and cell membrane fusion, making it an important target for developing vaccines, therapeutic antibodies and diagnosis. In this study, we constructed a baculovirus surface display system that efficiently presents both SARS-CoV and SARS-CoV-2 S proteins (including ectodomain, S1 subunit and receptor-binding-domain, RBD) on the surface of recombinant baculoviruses, utilizing transmembrane anchors from gp64 (signal peptide) and vesicular stomatitis virus (VSV). These recombinant baculoviruses were capable of transducing engineered HEK 293T cells overexpressing ACE2 receptors with significantly higher transduction efficiencies, indicating that S proteins displayed on baculovirus surface have antigenicity and can recognize and bind ACE2 receptors. Additionally, the transduction of SARS-CoV-2 S proteins can be inhibited by an antibody against the SARS-CoV-2 RBD. These results demonstrate that this baculovirus surface display system is a promising tool for developing antibodies, vaccines and recombinant protein production.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Enzima de Conversão de Angiotensina 2/genética , Baculoviridae/genética , Baculoviridae/metabolismo , Humanos , Ligação Proteica , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química
9.
BMC Cancer ; 22(1): 595, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641944

RESUMO

BACKGROUND: Part of papillary thyroid microcarcinoma (PTMC) has a high risk of tumor invasion and metastasis, which may occur in the regional lymph node metastasis or distant metastasis, severely threatening the life of patients. Invasion and metastasis are tightly involved in the proliferation, migration and invasion in cancer. This study aimed to investigate the role of tescalcin (TESC) in the proliferation, migration and invasion of PTMC. METHODS: The expressions of TESC in PTMC tissues and cells were detected by immunohistochemistry or qRT-PCR. Then, TPC-1 and BHT101 cells transfected with TESC-RNAi were used for the transcriptome sequencing. The proliferation, apoptosis, migration and invasion of TPC-1 and BHT101 cells were detected by CCK-8, colony formation, flow cytometric assay, transwell migration and scratch test. Moreover, TESC-RNAi transfected TPC-1 and BHT101 cells were subcutaneously injected into mice. Tumor volume and weight were calculated, and the positive rate of Ki-67 was determined by immunohistochemistry. Finally, the levels of c-Fos, ERK1/2 and p-ERK1/2 were determined by western blot. RESULTS: The expressions of TESC in PTMC tissues and cell lines were prominently enhanced. Transcriptome sequencing results showed that c-Fos was decreased in TPC-1 and BHT101 cells transfected with TESC-RNAi, which was associated with multiple different signaling pathways including the MAPK signaling pathway. Furthermore, TESC promoted the progress of PTMC by regulating the expression of c-Fos, which might be associated with the ERK signaling pathway. CONCLUSIONS: TESC promoted the growth and metastasis of PTMC through regulating c-Fos/ERK1/2.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Animais , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Proteínas Proto-Oncogênicas c-fos/genética , Transdução de Sinais , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
10.
EMBO Rep ; 21(8): e50095, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32558197

RESUMO

tRNA modifications at the anti-codon loop are critical for accurate decoding. FTSJ1 was hypothesized to be a human tRNA 2'-O-methyltransferase. tRNAPhe (GAA) from intellectual disability patients with mutations in ftsj1 lacks 2'-O-methylation at C32 and G34 (Cm32 and Gm34). However, the catalytic activity, RNA substrates, and pathogenic mechanism of FTSJ1 remain unknown, owing, in part, to the difficulty in reconstituting enzymatic activity in vitro. Here, we identify an interacting protein of FTSJ1, WDR6. For the first time, we reconstitute the 2'-O-methylation activity of the FTSJ1-WDR6 complex in vitro, which occurs at position 34 of specific tRNAs with m1 G37 as a prerequisite. We find that modifications at positions 32, 34, and 37 are interdependent and occur in a hierarchical order in vivo. We also show that the translation efficiency of the UUU codon, but not the UUC codon decoded by tRNAPhe (GAA), is reduced in ftsj1 knockout cells. Bioinformatics analysis reveals that almost 40% of the high TTT-biased genes are related to brain/nervous functions. Our data potentially enhance our understanding of the relationship between FTSJ1 and nervous system development.


Assuntos
Deficiência Intelectual , Códon , Humanos , Deficiência Intelectual/genética , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas Nucleares/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
11.
Nature ; 530(7588): 98-102, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26808898

RESUMO

Methyl-CpG binding protein 2 (MeCP2) has crucial roles in transcriptional regulation and microRNA processing. Mutations in the MECP2 gene are found in 90% of patients with Rett syndrome, a severe developmental disorder with autistic phenotypes. Duplications of MECP2-containing genomic segments cause the MECP2 duplication syndrome, which shares core symptoms with autism spectrum disorders. Although Mecp2-null mice recapitulate most developmental and behavioural defects seen in patients with Rett syndrome, it has been difficult to identify autism-like behaviours in the mouse model of MeCP2 overexpression. Here we report that lentivirus-based transgenic cynomolgus monkeys (Macaca fascicularis) expressing human MeCP2 in the brain exhibit autism-like behaviours and show germline transmission of the transgene. Expression of the MECP2 transgene was confirmed by western blotting and immunostaining of brain tissues of transgenic monkeys. Genomic integration sites of the transgenes were characterized by a deep-sequencing-based method. As compared to wild-type monkeys, MECP2 transgenic monkeys exhibited a higher frequency of repetitive circular locomotion and increased stress responses, as measured by the threat-related anxiety and defensive test. The transgenic monkeys showed less interaction with wild-type monkeys within the same group, and also a reduced interaction time when paired with other transgenic monkeys in social interaction tests. The cognitive functions of the transgenic monkeys were largely normal in the Wisconsin general test apparatus, although some showed signs of stereotypic cognitive behaviours. Notably, we succeeded in generating five F1 offspring of MECP2 transgenic monkeys by intracytoplasmic sperm injection with sperm from one F0 transgenic monkey, showing germline transmission and Mendelian segregation of several MECP2 transgenes in the F1 progeny. Moreover, F1 transgenic monkeys also showed reduced social interactions when tested in pairs, as compared to wild-type monkeys of similar age. Together, these results indicate the feasibility and reliability of using genetically engineered non-human primates to study brain disorders.


Assuntos
Transtorno Autístico/genética , Transtorno Autístico/psicologia , Modelos Animais de Doenças , Mutação em Linhagem Germinativa/genética , Hereditariedade/genética , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Animais , Animais Geneticamente Modificados , Ansiedade/genética , Ansiedade/psicologia , Transtorno Autístico/metabolismo , Transtorno Autístico/fisiopatologia , Encéfalo/metabolismo , Cognição/fisiologia , Feminino , Humanos , Locomoção/genética , Locomoção/fisiologia , Macaca fascicularis , Masculino , Fenótipo , Comportamento Social , Injeções de Esperma Intracitoplásmicas , Transgenes/genética
12.
Plant Dis ; 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35612578

RESUMO

The macadamia industry is developing rapidly in China. A brown leaf spot disease was noted in six Macadamia integrifolia plantations in Lincang, Yunnan, in October 2021. Over 60% of trees sampled had brown leaf spot symptoms, among approx.15,000 trees planted in these areas. Lesions (3 to 5 mm dia.) were small round brown spots with yellow edges. Lesions on severely infected leaves were darker and larger, with irregular shape (8 to 10 mm long, 3 to 6 mm wide). About 10% of diseased leaves had lesions characterized by a shot hole surrounded by a yellow halo. Potential pathogens were isolated from four randomly-selected symptomatic leaves from each of the six plantations by cutting lesion edges into small pieces. The pieces were surface sterilized, placed onto water agar containing 100 ppm aureomycin and incubated for 5 days at 24°C in the dark. Subculturing microbial growth on potato dextrose agar produced single-hyphal isolates with white fluffy aerial mycelia that turned pale olivaceous gray after 4 to 5 days. In four randomly-selected cultures, conidia were single celled, hyaline, spindle shaped to oval, and measured 10.9 to 16.3 µm long and 4.0 to 6.2 µm wide (n = 50). These characteristics matched those of Neofusicoccum parvum (Pavlic et al. 2009). Isolate LC013 was randomly selected as a representative individual for molecular identification. Internal transcribed spacer (ITS; ITS1/ITS4 primers; White et al. 1990), beta-tubulin gene (tub2; BT2A/BT2B primers; Glass and Donaldson 1995) and translation elongation factor 1-alpha gene (tef1-α; EF1-728F/EF2 primers; Carbone and Kohn 1999; O'Donnell et al. 1998) regions were PCR amplified from genomic DNA. Sequences of the products were used to BLAST probe the type specimen nucleotide sequences in GenBank. The LC013 sequences (GenBank accessions OM392021 (ITS); OM453641 (tub2); OM567656 (tef1-α)) had >99% sequence identity with analogous sequences from the type specimen of N. parvum CBS 138823 (accessions AY236943 (ITS); AY236917 (tub2); AY236888 (tef1-α)). Isolate LC013 was sister to N. parvum type strain in a maximum-likelihood (ML) tree constructed from analogous concatenated ITS, tef1-α, and tub2 sequences of 27 species that are phylogenetically closely-related to LC013 based on the ITS single locus ML tree. Koch's postulates were tested twice with two isolates by wounding leaves of four 14-month-old M. integrifolia seedlings with a sterile needle and placing a 5-mm-diameter agar plug containing N. parvum on the wound site. PDA plugs alone were used as uninoculated controls. Leaves were covered with sealed bags to maintain >90% humidity for 24 hours. All plants were kept in the same glasshouse under natural conditions. Leaves of inoculated plants began to discolor at 5 days post-inoculation (dpi). Brown spot symptoms were observed at 9 dpi. Control plants were symptomless. N. parvum was re-isolated from leaf lesions of the infected plants, but not from control plants, thus fulfilling Koch's postulates. N. parvum is an aggressive pathogen that causes severe disease on important tree and woody species, including M. integrifolia (Liddle et al. 2019). In China, it has been reported to cause leaf spot disease on 26 plant species (Farr and Rossman 2022), but this is the first report of N. parvum causing leaf spot disease on M. integrifolia. Further investigation is required to estimate the importance of this pathogen to the macadamia industry in China.

13.
BMC Cancer ; 21(1): 862, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315439

RESUMO

BACKGROUND: Here we evaluated the feasibility, efficacy, tolerability, and treatment-mediated immune modulation of neoadjuvant everolimus plus letrozole versus chemotherapy in treating postmenopausal patients with ER-positive, HER2-negative breast cancer. METHODS: Postmenopausal women with ER-positive, HER2-negative breast cancer who had a primary tumor > 2 cm or positive axillary lymph node(s) proofed by biopsy were randomly (1,1) enrolled to receive neoadjuvant everolimus plus letrozole for 18 weeks or fluorouracil, epirubicin plus cyclophosphamide (FEC) for 6 cycles before surgery. Primary outcome was feasibility of the trial. Secondary outcome included ultrasound response rate, pathological complete response rate, breast-conserving surgery rate, toxicities, treatment-mediated immune modulation and biomarkers. RESULTS: Forty patients were randomized. Completion rate was 90.0% in the neoadjuvant endocrine therapy (NET) arm but 70.0% in the neoadjuvant chemotherapy (NAC) arm. The ultrasound response rate was 65.0% in NET arm and 40.0% in FEC arm, respectively. In terms of the adverse events, clearly favored NET arm. Everolimus plus letrozole increased the ratio of peripheral Tregs to CD4+ T cells and tumor PD-L1 expression, and decreased Ki67 index and tumor-infiltrating Tregs, and patients with a greater increase of tumor-specific CTLs showed more sensitive to NET. CONCLUSION: This pilot trial showed that neoadjuvant everolimus plus letrozole might achieve a favorable ultrasound response rate with low toxicities in treating postmenopausal ER-positive, HER2-negative breast cancer patients. Everolimus plus letrozole might have positive antitumoral immunity effects. Further large randomized controlled trials are needed to confirm our findings. TRAIL REGISTRATION: A Trial of Neoadjuvant Everolimus Plus Letrozole Versus FEC in Women With ER-positive, HER2-negative Breast Cancer, registered on 07/04/2016 and first posted on 18/04/2016, NCT02742051 .


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/etiologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Biópsia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Everolimo/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Letrozol/administração & dosagem , Pessoa de Meia-Idade , Projetos Piloto , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Resultado do Tratamento
14.
Proc Natl Acad Sci U S A ; 115(32): E7469-E7477, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30042215

RESUMO

Acid-sensing ion channels (ASICs) have emerged as important, albeit challenging therapeutic targets for pain, stroke, etc. One approach to developing therapeutic agents could involve the generation of functional antibodies against these channels. To select such antibodies, we used channels assembled in nanodiscs, such that the target ASIC1a has a configuration as close as possible to its natural state in the plasma membrane. This methodology allowed selection of functional antibodies that inhibit acid-induced opening of the channel in a dose-dependent way. In addition to regulation of pH, these antibodies block the transport of cations, including calcium, thereby preventing acid-induced cell death in vitro and in vivo. As proof of concept for the use of these antibodies to modulate ion channels in vivo, we showed that they potently protect brain cells from death after an ischemic stroke. Thus, the methodology described here should be general, thereby allowing selection of antibodies to other important ASICs, such as those involved in pain, neurodegeneration, and other conditions.


Assuntos
Bloqueadores do Canal Iônico Sensível a Ácido/farmacologia , Canais Iônicos Sensíveis a Ácido/imunologia , Apoptose/efeitos dos fármacos , Infarto Encefálico/tratamento farmacológico , Anticorpos de Cadeia Única/farmacologia , Bloqueadores do Canal Iônico Sensível a Ácido/química , Bloqueadores do Canal Iônico Sensível a Ácido/uso terapêutico , Animais , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Infarto Encefálico/etiologia , Células CHO , Artérias Cerebrais , Cricetulus , Modelos Animais de Doenças , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular/métodos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/uso terapêutico
15.
Crit Rev Immunol ; 39(1): 59-81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679194

RESUMO

Signaling from the T cell receptor for antigen turns on the physiological response of a T cell. The canonical TCR signaling pathway relies on early activation of the Src kinase LCK. This step initiates a cascade of events that lead not only to the phenotypic changes that characterize effector T cells but also to the activation of negative regulatory mechanisms that stop early TCR signaling. These mechanisms ensure qualitative and quantitative fine-tuning of T cell activation. The tyrosine phosphatase SHP-1 is a key player in the downregulation of LCK activation. In this review, we focus on the crosstalk between LCK and SHP-1 and, based on recent data, we introduce the putative kinase TAOK3 as an important regulator of this crosstalk. Given the widespread expression of TAOK3 and SHP-1, we propose that the function of TAOK3 extends beyond T cells and may be fundamental in the regulation of early signaling from receptors that utilize Src kinases.


Assuntos
Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Linfócitos T/imunologia , Animais , Humanos , Ativação Linfocitária , Receptor Cross-Talk , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
16.
Antonie Van Leeuwenhoek ; 113(10): 1425-1435, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32696278

RESUMO

A novel Gram-stain negative, aerobic, non-motile, rod-shaped bacterium, designated as strain EB310T, was isolated from rhizosphere soil of mangrove plant Kandelia candel in Fugong village, Zhangzhou, China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain EB310T belonged to the genus Erythrobacter, clustering with Erythrobacter pelagi JCM 17468T, Erythrobacter lutimaris KCTC 42109T and Erythrobacter marisflavi KCTC 62896T, and showed the highest 16S rRNA gene sequence similarity of 97.5% to Erythrobacter pelagi JCM 17468T. The genomic average nucleotide identity and in silico DNA-DNA hybridization values between strain EB310T and the reference strains were 71.0-75.5% and 19.8-20.0%, respectively. Growth ranges of the isolate occurred at 10-45 °C (optimum 28-30 °C), pH 5.5-9.5 (optimum pH 7.5) and 0-9.0% NaCl concentrations (optimum 2.0%, w/v). The strain did not produce bacteriochlorophyll a and flexirubin, but produced carotenoids. The strain contained Q-10 as the predominant ubiquinone and summed feature 3 (C16:1 ω7c/C16:1 ω6c) and summed feature 8 (C18:1 ω6c/C18:1 ω7c) as the major fatty acids. The major polar lipids were sphingoglycolipid, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylcholine. Differential phenotypic characteristics, together with chemotaxonomic, phylogenetic and genomic distinctiveness, indicated that strain EB310T is distinguishable from other members of the genus Erythrobacter. On the basis of the data exhibited, strain EB310T is considered to represent a novel species of the genus Erythrobacter, for which the name Erythrobacter mangrovi sp. nov., is proposed. The type strain is EB310T (= KCTC 72109T = MCCC 1K03690T). The genomic DNA G + C content is 62.9 mol%.


Assuntos
Técnicas de Tipagem Bacteriana , Rhizophoraceae/microbiologia , Rizosfera , Microbiologia do Solo , Sphingomonadaceae/classificação , Sphingomonadaceae/isolamento & purificação , Biologia Computacional/métodos , Código de Barras de DNA Taxonômico , Mineração de Dados , Genoma Bacteriano , Genômica/métodos , Filogenia , RNA Ribossômico 16S/genética , Sphingomonadaceae/química , Sphingomonadaceae/genética
17.
Curr Microbiol ; 77(5): 762-768, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31919672

RESUMO

Emcibacter congregatus ZYLT was isolated from a sediment sample cultured in situ in a coast located in the East China Sea. The genome of E. congregatus ZYLT was sequenced and assembled into one single circular chromosome with the size of 4,189,011 bp and G+C content of 52.6%. Genomic annotation showed that E. congregatus ZYLT had an intact Type II-C CRISPR-Cas system consists of three cas genes (cas 9, cas 1, and cas 2), 34 direct repeat sequences with the length of 36 bp, and 33 spacers. The predicted Cas 9 protein was smaller than most of existing genome editing tools. This structure might have potential in developing new gene editing system and uncovering the regulatory mechanisms of CRISPR-Cas system. Besides, the comparison between E. congregatus ZYLT and its relative species living in neritic environments unraveled some common traits of the defective strategies of these bacteria to face inshore challenges including the motility, multidrug resistance, and universal efflux pumps.


Assuntos
Alphaproteobacteria/genética , Sistemas CRISPR-Cas/genética , Genoma Bacteriano , Organismos Aquáticos/genética , Composição de Bases , China , Edição de Genes , Genômica , Sedimentos Geológicos/microbiologia , Filogenia , Análise de Sequência de DNA
18.
Semin Cell Dev Biol ; 69: 131-139, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28478299

RESUMO

The cluster of almost 60 protocadherin genes, divided into the α, ß and γ subgroups, is a hallmark of vertebrate nervous system evolution. These clustered protocadherins (Pcdhs) are of interest for several reasons, one being the arrangement of the genes, which allows epigenetic regulation at the cluster and single-cell identity. Another reason is the still ambiguous effect of Pcdhs on cell-cell interaction. Unlike the case for classical cadherins, which typically mediate strong cell adhesion and formation of adherens junctions, it has been challenging to ascertain exactly how Pcdhs affect interacting cells. In some instances, Pcdhs appear to promote the association of membranes, while in other cases the Pcdhs are anti-adhesive and cause avoidance of interacting membranes. It is clear that Pcdh extracellular domains bind homophillically in an antiparallel conformation, typical of adhesive interactions. How can molecules that would seemingly bind cells together be able to promote the avoidance of membranes? It is possible that Pcdh trafficking will eventually provide insights into the role of these molecules at the cell surface. We have found that endogenous and expressed Pcdhs are generally less efficient at targeting to cell junctions and synapses than are classical cadherins. Instead, Pcdhs are prominently sequestered in the endolysosome system or other intracellular compartments. What role this trafficking plays in the unique mode of cell-cell interaction is a current topic of investigation. It is tempting to speculate that modulation of endocytosis and endolysosomal trafficking may be a part of the mechanism by which Pcdhs convert from adhesive to avoidance molecules.


Assuntos
Caderinas/metabolismo , Sequência de Aminoácidos , Animais , Caderinas/química , Caderinas/genética , Membrana Celular/metabolismo , Endocitose , Humanos , Modelos Biológicos , Transporte Proteico , Sinapses/metabolismo
19.
Biochem Biophys Res Commun ; 516(2): 540-545, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31235255

RESUMO

Histidine biosynthesis, which is absent in animals, was shown to be highly conserved among gram-negative bacteria, thus making it an attractive target for antibiotic design. There are many fusion forms of enzymes in the histidine biosynthetic pathway and people still have limited knowledge about their domain organizations and catalytic mechanisms, due to the lack of structural information. Here we report the first crystal structure of Shigella flexneri bi-functional enzyme HisIE (SfHisIE) that functions in the 2nd and 3rd steps in the histidine biosynthetic pathway. This structure shows that HisIE exists as dimers with two loops (fusion loop) connecting the individual dimer of HisE and HisI in its N-terminus and C-terminus respectively. Our mutagenesis study shows mutations in this fusion loop are lethal for bacteria indicating the advantage of gene fusion in Histidine biosynthesis. Structural analysis revealed several highly conserved residues in the putative ligand binding grooves of HisE and HisI, showing an evolutionarily conserved catalytic mechanism shared among gram negative-bacteria.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Histidina/biossíntese , Shigella flexneri/enzimologia , Sequência de Aminoácidos , Biocatálise , Modelos Moleculares , Domínios Proteicos , Estrutura Secundária de Proteína
20.
BMC Cancer ; 19(1): 372, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014268

RESUMO

BACKGROUND: As the efficacy of radiotherapy and chemotherapy for treatment of phyllodes tumors (PTs) remains unclear, this study aimed to review all available data and evaluate the roles of radiotherapy and chemotherapy in PT treatment. METHODS: We performed a comprehensive search of databases, including PubMed, Web of Science and the Cochrane Library. The outcomes of interest included the local recurrence (LR) rate, metastasis rate, disease-free survival rate and overall survival rate. RESULTS: Seventeen studies enrolling 696 patients were included in this random effect meta-analysis. Subgroup analysis and meta-regression were also conducted to determine study heterogeneity. A pooled local recurrence rate of 8% (95% CI: 1-22%) was observed with a statistical heterogeneity of I2 = 86.6% (p < 0.01) for radiotherapy. This was lower than the recurrence rate of 12% for simple surgical treatment (95% CI: 7-18%). Meta-regression analysis found that surgical margin status was the main source of heterogeneity (p = 0.04). The metastasis rate of 4% (95% CI: 0-11%) for patients receiving radiotherapy without significant heterogeneity was also lower than the rate for the simple surgery group (8, 95% CI: 3-15%). The available data for chemotherapy were too limited to support meta-analysis. Accordingly, we offer a pure review of these data. CONCLUSION: Our findings suggest that radiotherapy is effective in achieving local disease control and preventing metastasis.


Assuntos
Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante/mortalidade , Recidiva Local de Neoplasia/mortalidade , Tumor Filoide/mortalidade , Radioterapia Adjuvante/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Feminino , Humanos , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Tumor Filoide/patologia , Tumor Filoide/terapia , Prognóstico , Taxa de Sobrevida
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