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1.
Acta Pharmacol Sin ; 44(11): 2243-2252, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37407703

RESUMO

Group 3 innate lymphoid cells (ILC3s) are mediators of intestinal immunity and barrier function. Recent studies have investigated the role of the mammalian target of rapamycin complex (mTOR) in ILC3s, whereas the mTORC1-related mechanisms and crosstalk between mTORC1 and mTORC2 involved in regulating ILC3 homeostasis remain unknown. In this study, we found that mTORC1 but not mTORC2 was critical in ILC3 development, IL-22 production, and ILC3-mediated intestinal homeostasis. Single-cell RNA sequencing revealed that mTORC1 deficiency led to disruption of ILC3 heterogeneity, showing an increase in differentiation into ILC1-like phenotypes. Mechanistically, mTORC1 deficiency decreased the expression of NFIL3, which is a critical transcription factor responsible for ILC3 development. The activities of both mTORC1 and mTORC2 were increased in wild-type ILC3s after activation by IL-23, whereas inhibition of mTORC1 by Raptor deletion or rapamycin treatment resulted in increased mTORC2 activity. Previous studies have demonstrated that S6K, the main downstream target of mTORC1, can directly phosphorylate Rictor to dampen mTORC2 activity. Our data found that inhibition of mTORC1 activity by rapamycin reduced Rictor phosphorylation in ILC3s. Reversing the increased mTORC2 activity via heterozygous or homozygous knockout of Rictor in Raptor-deleted ILC3s resulted in severe ILC3 loss and complete susceptibility to intestinal infection in mice with mTORC1 deficiency (100% mortality). Thus, mTORC1 acts as a rheostat of ILC3 heterogeneity, and mTORC2 protects ILC3s from severe loss of cells and immune activity against intestinal infection when mTORC1 activity is diminished.


Assuntos
Imunidade Inata , Linfócitos , Camundongos , Animais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Proteína Regulatória Associada a mTOR/genética , Fatores de Transcrição/metabolismo , Sirolimo/farmacologia , Mamíferos/metabolismo
2.
J Fungi (Basel) ; 8(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36547635

RESUMO

Hydnobolites is an ectomycorrhizal fungal genus with hypogeous ascomata in the family Pezizaceae (Pezizales). Molecular analyses of Hydnobolites using both single (ITS) and concatenated gene datasets (ITS-nLSU) showed a total of 223 sequences, including 92 newly gained sequences from Chinese specimens. Phylogenetic results based on these two datasets revealed seven distinct phylogenetic clades. Among them, the ITS phylogenetic tree confirmed the presence of at least 42 phylogenetic species in Hydnobolites. Combined the morphological observations with molecular analyses, five new species of Hydnobolites translucidus sp. nov., H. subrufus sp. nov., H. lini sp. nov., H. sichuanensis sp. nov. and H. tenuiperidius sp. nov., and one new record species of H. cerebriformis Tul., were illustrated from Southwest China. Macro- and micro-morphological analyses of ascomata revealed a few, but diagnostic differences between the H. cerebriformis complex, while the similarities of the ITS sequences ranged from 94.4 to 97.2% resulting in well-supported clades.

3.
Mycorrhiza ; 32(3-4): 341-351, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35608677

RESUMO

Truffle cultivation has drawn more and more attention for its high economic and ecological values in the world. To select symbionts suitable for cultivation purposes, we conducted greenhouse-based mycorrhization trials of two Tuber species (T. formosanum and T. pseudohimalayense) with five broad-leaved tree species (Corylus yunnanensis, Quercus aliena var. acutiserrata, Q. acutissima, Q. robur, Q. variabilis) and one conifer species (Pinus armandii). Axenically germinated seedlings of all tree species were either inoculated, or not, with spore suspensions of these two truffles in the greenhouse. Eight months after inoculation, T. formosanum or T. pseudohimalayense ectomycorrhizae were successfully formed on these six tree species, as evidenced by both morphological and molecular analyses. All selected trees showed good receptivity to mycorrhization by both fungi, with average colonization rates visually estimated at 40-50%. Plant growth, photosynthesis, and nutrient uptake were assessed 2 years after inoculation and were mainly affected by host species. Mycorrhization by both fungi significantly improved P uptake of the hosts, and the interaction between truffle species and host plant species had significant effects on leaf water and leaf K concentrations. In addition, a significantly negative correlation between leaf Ca and leaf C concentration was found across all the seedlings. In addition, mycorrhization had slightly increased plant stem and canopy, but had no significant effects on plant photosynthesis. Overall, these results suggest that the effects of these two Tuber ECMF on plant growth and nutrient acquisition depend on the identity of the host species. Moreover, all selected plant species could be symbiotic partners with either T. pseudohimalayense or T. formosanum for field cultivation purposes.


Assuntos
Ascomicetos , Micorrizas , Quercus , Quercus/microbiologia , Plântula/microbiologia , Árvores/microbiologia
4.
Chaos ; 31(3): 031103, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33810742

RESUMO

The standard definition of the Riemann-Liouville integral is revisited. A new fractional integral is proposed with an exponential kernel. Furthermore, some useful properties such as composition relationship of the new fractional integral and Leibniz integral law are provided. Exact solutions of the fractional homogeneous equation and the non-homogeneous equations are given, respectively. Finally, a finite difference scheme is proposed for solving fractional nonlinear differential equations with exponential memory. The results show the efficiency and convenience of the new fractional derivative.

5.
Mycoscience ; 62(5): 322-330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37089468

RESUMO

Truffle cultivation is successfully applied throughout the world for several truffles of European origin. However, just two Chinese black truffles (Tuber indicum and T. himalayense) have been cultivated with a favorable outcome so far. Tuber pseudohimalayense is a black truffle of significant economic relevance in China, but little is known about its mycorrhizal ecology and it is not cultivated in orchards yet. Here, we selected seven broad-leaved tree species (Quercus fabrei, Q. aliena, Castanea mollissima, Carya illinoinensis, Q. glauca, Castanopsis orthacantha, Betula costata), and one coniferous tree (Pinus armandii), and inoculated them with T. pseudohimalayense spore suspension using axenically germinated seedlings under greenhouse conditions. The obtained mycorrhizae, well-developed, were analyzed from the morpho-anatomical and molecular points of view, and their main characteristics described. Synthesized T. pseudohimalayense mycorrhizae showed similar characters on all tree species, with a typical interlocking pseudoparenchymatous mantle and Hartig net, swollen appearance, yellow-brownish color, and long hyaline emanating hyphae with right-angle ramifications. These features are similar to those reported for mycorrhizae formed by related black truffle species. The successful mycorrhizal synthesis of T. pseudohimalayense on multiple trees species indicates that it has potential for cultivation in China.

6.
Mycorrhiza ; 29(6): 649-661, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31760479

RESUMO

We aimed to test whether Tuber melanosporum and native Chinese oak species could form stable mycorrhizal symbioses. Six oak species were all either inoculated or not, with spores of the Périgord black truffle in the greenhouse. Ectomycorrhizal development was monitored for up to 32 months. Seedling growth was assessed 2 years after inoculation. From 6 months after inoculation, Tuber melanosporum ectomycorrhizae were successfully produced on five Quercus species endemic to China, as shown by morphological, anatomical, and molecular analyses. Quercus mongolica and Q. longispica showed high receptivity to mycorrhization by T. melanosporum. The symbioses obtained with these two species and with Quercus senescens were stable for at least 32 months. Averaged over all three oak species, mycorrhization by T. melanosporum significantly enhanced canopy diameter, number of leaves, and mean leaf dimension. In spring 2019, mycorrhization by T. melanosporum accelerated budbreak in Q. mongolica. Quercus fabrei and Q. variabilis formed ectomycorrhizae up to 9 months after inoculation but seedlings died 3 months later, probably because of damage by grazing insects. Quercus pseudosemecarpifolia failed to form ectomycorrhizae. Results suggest that T. melanosporum-mycorrhized Q. mongolica and Q. longispica seedlings could be tested for ascocarp production and increased performance in the field.


Assuntos
Ascomicetos , Micorrizas , Quercus , China , Plântula
7.
Yi Chuan ; 38(9): 831-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27644744

RESUMO

In animal cells, inhibition of non-homologous end joining (NHEJ) pathway improves the efficiency of homologous recombination (HR)-mediated double-strand brakes (DSBs) repair. To improve the efficiency of HR in sheep embryo fibroblasts, the NHEJ key molecule DNA ligase 4 (Lig4) was suppressed by siRNA interference. Four pairs of siRNA targeting Lig4 were designed and chemically synthesized. These siRNA were electro-transferred into sheep embryo fibroblasts respectively. Compared with the control groups, two pairs of siRNA were identified to effectively inhibit the expression of sheep Lig4 gene by qRT-PCR and Western blotting. The plasmid rejoining assay was adopted for examining the efficiency of HR-mediated DSB repair. I-SceⅠ endonuclease linearized vector and siRNA were co-transfected into sheep embryo fibroblasts. Flow cytometry analysis of cells after transfection for 72 h showed that suppression of Lig4 using siRNAs increased the rejoining efficiency of HR vector by 3-4 times compared with the control groups. Therefore, enhanced HR vector rejoining frequency by instant inhabition of Lig4 gene provides theoretical basis for improving gene targeting efficiency of sheep embryo fibroblasts.


Assuntos
DNA Ligases/genética , Fibroblastos/metabolismo , Recombinação Homóloga/genética , RNA Interferente Pequeno/genética , Reparo de DNA por Recombinação/genética , Ovinos/genética , Animais , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Proteínas de Ligação a DNA/genética , Marcação de Genes/métodos , Proteínas Nucleares/genética , Ovinos/metabolismo
8.
Zhong Yao Cai ; 32(4): 508-11, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19645232

RESUMO

OBJECTIVE: To study the chemical constituents of the flower buds of Daphne genkwa. METHODS: The constituents of petroleum ether and ethyl acetate-soluble portions were isolated and purified by means of chromatography, then they were identified by their physico-chemical characteristics and spectral features. RESULTS: Ten compounds were isolated and identified as octacosane (1), dotriacontane (2), beta-sitosterol (3), 4', 7-dimethoxy-5-hydroxyflovone (4), aurantiamide acetate (5), genkwanin (6), luteolin (7), apigenin (8), 3'-hydroxygenkwanin (9) and daphnoretin (10). CONCLUSION: Compound 1 and 2 are isolated from this plant for the first time.


Assuntos
Alcanos/isolamento & purificação , Daphne/química , Diacetil/isolamento & purificação , Dipeptídeos/isolamento & purificação , Plantas Medicinais/química , Alcanos/química , Apigenina/química , Apigenina/isolamento & purificação , Cumarínicos/química , Cumarínicos/isolamento & purificação , Diacetil/química , Dipeptídeos/química , Flavonas/química , Flavonas/isolamento & purificação , Flores/química , Luteolina/química , Luteolina/isolamento & purificação , Estrutura Molecular , Sitosteroides/química , Sitosteroides/isolamento & purificação
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