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1.
Nat Commun ; 15(1): 5680, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971819

RESUMO

Obesity shapes anti-tumor immunity through lipid metabolism; however, the mechanisms underlying how colorectal cancer (CRC) cells utilize lipids to suppress anti-tumor immunity remain unclear. Here, we show that tumor cell-intrinsic ATP6V0A1 drives exogenous cholesterol-induced immunosuppression in CRC. ATP6V0A1 facilitates cholesterol absorption in CRC cells through RAB guanine nucleotide exchange factor 1 (RABGEF1)-dependent endosome maturation, leading to cholesterol accumulation within the endoplasmic reticulum and elevated production of 24-hydroxycholesterol (24-OHC). ATP6V0A1-induced 24-OHC upregulates TGF-ß1 by activating the liver X receptor (LXR) signaling. Subsequently, the release of TGF-ß1 into the tumor microenvironment by CRC cells activates the SMAD3 pathway in memory CD8+ T cells, ultimately suppressing their anti-tumor activities. Moreover, we identify daclatasvir, a clinically used anti-hepatitis C virus (HCV) drug, as an ATP6V0A1 inhibitor that can effectively enhance the memory CD8+ T cell activity and suppress tumor growth in CRC. These findings shed light on the potential for ATP6V0A1-targeted immunotherapy in CRC.


Assuntos
Linfócitos T CD8-Positivos , Colesterol , Neoplasias Colorretais , Transdução de Sinais , Fator de Crescimento Transformador beta1 , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Humanos , Animais , Colesterol/metabolismo , Camundongos , Linhagem Celular Tumoral , Fator de Crescimento Transformador beta1/metabolismo , Memória Imunológica , ATPases Vacuolares Próton-Translocadoras/metabolismo , Microambiente Tumoral/imunologia , Receptores X do Fígado/metabolismo , Hidroxicolesteróis/metabolismo , Hidroxicolesteróis/farmacologia , Pirrolidinas/farmacologia , Proteína Smad3/metabolismo , Camundongos Endogâmicos C57BL , Carbamatos/farmacologia
2.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473781

RESUMO

The Tripterospermum, comprising 34 species, is a genus of Gentianaceae. Members of Tripterospermum are mostly perennial, entwined herbs with high medicinal value and rich in iridoids, xanthones, flavonoids, and triterpenes. However, our inadequate understanding of the differences in the plastid genome sequences of Tripterospermum species has severely hindered the study of their evolution and phylogeny. Therefore, we first analyzed the 86 Gentianae plastid genomes to explore the phylogenetic relationships within the Gentianae subfamily where Tripterospermum is located. Then, we analyzed six plastid genomes of Tripterospermum, including two newly sequenced plastid genomes and four previously published plastid genomes, to explore the plastid genomes' evolution and phylogenetic relationships in the genus Tripterospermum. The Tripterospermum plastomes have a quadripartite structure and are between 150,929 and 151,350 bp in size. The plastomes of Tripterospermum encoding 134 genes were detected, including 86 protein-coding genes (CDS), 37 transfer RNA (tRNA) genes, eight ribosomal RNA (rRNA) genes, and three pseudogenes (infA, rps19, and ycf1). The result of the comparison shows that the Tripterospermum plastomes are very conserved, with the total plastome GC content ranging from 37.70% to 37.79%. In repeat sequence analysis, the number of single nucleotide repeats (A/T) varies among the six Tripterospermum species, and the identified main long repeat types are forward and palindromic repeats. The degree of conservation is higher at the SC/IR boundary. The regions with the highest divergence in the CDS and the intergenic region (IGS) are psaI and rrn4.5-rrn5, respectively. The average pi of the CDS and the IGS are only 0.071% and 0.232%, respectively, indicating that the Tripterospermum plastomes are highly conserved. Phylogenetic analysis indicated that Gentianinae is divided into two clades, with Tripterospermum as a sister to Sinogeniana. Phylogenetic trees based on CDS and CDS + IGS combined matrices have strong support in Tripterospermum. These findings contribute to the elucidation of the plastid genome evolution of Tripterospermum and provide a foundation for further exploration and resource utilization within this genus.


Assuntos
Genomas de Plastídeos , Gentianaceae , Filogenia , Evolução Molecular
3.
BMC Genomics ; 24(1): 749, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057701

RESUMO

BACKGROUND: Chiloschista (Orchidaceae, Aeridinae) is an epiphytic leafless orchid that is mainly distributed in tropical or subtropical forest canopies. This rare and threatened orchid lacks molecular resources for phylogenetic and barcoding analysis. Therefore, we sequenced and assembled seven complete plastomes of Chiloschista to analyse the plastome characteristics and phylogenetic relationships and conduct a barcoding investigation. RESULTS: We are the first to publish seven Chiloschista plastomes, which possessed the typical quadripartite structure and ranged from 143,233 bp to 145,463 bp in size. The plastomes all contained 120 genes, consisting of 74 protein-coding genes, 38 tRNA genes and eight rRNA genes. The ndh genes were pseudogenes or lost in the genus, and the genes petG and psbF were under positive selection. The seven Chiloschista plastomes displayed stable plastome structures with no large inversions or rearrangements. A total of 14 small inversions (SIs) were identified in the seven Chiloschista plastomes but were all similar within the genus. Six noncoding mutational hotspots (trnNGUU-rpl32 > rpoB-trnCGCA > psbK-psbI > psaC-rps15 > trnEUUC-trnTGGU > accD-psaI) and five coding sequences (ycf1 > rps15 > matK > psbK > ccsA) were selected as potential barcodes based on nucleotide diversity and species discrimination analysis, which suggested that the potential barcode ycf1 was most suitable for species discrimination. A total of 47-56 SSRs and 11-14 long repeats (> 20 bp) were identified in Chiloschista plastomes, and they were mostly located in the large single copy intergenic region. Phylogenetic analysis indicated that Chiloschista was monophyletic. It was clustered with Phalaenopsis and formed the basic clade of the subtribe Aeridinae with a moderate support value. The results also showed that seven Chiloschista species were divided into three major clades with full support. CONCLUSION: This study was the first to analyse the plastome characteristics of the genus Chiloschista in Orchidaceae, and the results showed that Chiloschista plastomes have conserved plastome structures. Based on the plastome hotspots of nucleotide diversity, several genes and noncoding regions are suitable for phylogenetic and population studies. Chiloschista may provide an ideal system to investigate the dynamics of plastome evolution and DNA barcoding investigation for orchid studies.


Assuntos
Genoma de Cloroplastos , Genomas de Plastídeos , Orchidaceae , Filogenia , Código de Barras de DNA Taxonômico , Orchidaceae/genética , Nucleotídeos
4.
Int J Mol Sci ; 24(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37894943

RESUMO

The Elsholtzieae, comprising ca. 7 genera and 70 species, is a small tribe of Lamiaceae (mint family). Members of Elsholtzieae are of high medicinal, aromatic, culinary, and ornamentals value. Despite the rich diversity and value of Elsholtzieae, few molecular markers or plastomes are available for phylogenetics. In the present study, we employed high-throughput sequencing to assemble two Mosla plastomes, M. dianthera and M. scabra, for the first time, and compared with other plastomes of Elsholtzieae. The plastomes of Elsholtzieae exhibited a quadripartite structure, ranging in size from 148,288 bp to 152,602 bp. Excepting the absence of the pseudogene rps19 in Elsholtzia densa, the exhaustive tally revealed the presence of 132 genes (113 unique genes). Among these, 85 protein-coding genes (CDS), 37 tRNA genes, 8 rRNA genes, and 2 pseudogenes (rps19 and ycf1) were annotated. Comparative analyses showed that the plastomes of these species have minor variations at the gene level. Notably, the E. eriostchya plastid genome exhibited increased GC content regions in the LSC and SSC, resulting in an increased overall GC content of the entire plastid genome. The E. densa plastid genome displayed modified boundaries due to inverted repeat (IR) contraction. The sequences of CDS and intergenic regions (IGS) with elevated variability were identified as potential molecular markers for taxonomic inquiries within Elsholtzieae. Phylogenetic analysis indicated that four genera formed monophyletic entities, with Mosla and Perilla forming a sister clade. This clade was, in turn, sister to Collinsonia, collectively forming a sister group to Elsholtzia. Both CDS, and CDS + IGS could construct a phylogenetic tree with stronger support. These findings facilitate species identification and DNA barcoding investigations in Elsholtzieae and provide a foundation for further exploration and resource utilization within this tribe.


Assuntos
Genomas de Plastídeos , Lamiaceae , Filogenia , Lamiaceae/genética
5.
iScience ; 26(10): 107895, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37766970

RESUMO

Laser irradiation is a powerful tool in inducing changes in lattice structures and properties of two-dimensional (2D) materials through processes such as heating, bleaching, catalysis, etc. However, the underlying mechanisms of such transformations vary dramatically in different 2D materials. Here, we report the structural transformation of layered titanium trisulfide (TiS3) to titanium disulfide (TiS2) after irradiation. We systematically characterized the dependence of the transformation on laser power, flake thickness, irradiation time, and vacuum conditions using microscopic and spectroscopic methods. The underlying mechanism is confirmed as the heat-induced materials decomposition, a process that also occurs in many other transition metal trichalcogenide materials. Furthermore, we demonstrate that this spatial-resolved method also enables the creation of in-plane TiS3-TiS2 heterostructures. Our study identifies a new family of 2D materials that undergo a structural transformation after laser irradiation and enriches the methods available for developing new prototypes of low-dimensional devices in the future.

6.
Oncogene ; 42(41): 3062-3074, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37634009

RESUMO

Gastric cancer (GC) is characterized by its vigorous chemoresistance to current therapies, which is attributed to the highly heterogeneous and immature phenotype of cancer stem cells (CSCs) during tumor initiation and progression. The secretory WNT2 ligand regulates multiple cancer pathways and has been demonstrated to be a potential therapeutic target for gastrointestinal tumors; however, its role involved in gastric CSCs (GCSCs) remains unclear. Here, we found that overexpression of WNT2 enhanced stemness properties to promote chemoresistance and tumorigenicity in GCSCs. Mechanistically, WNT2 was positively regulated by its transcription factor SOX4, and in turn, SOX4 was upregulated by the canonical WNT2/FZD8/ß-catenin signaling pathway to form an auto-regulatory positive feedback loop, resulting in the maintenance of GCSCs self-renewal and tumorigenicity. Furthermore, simultaneous overexpression of both WNT2 and SOX4 was correlated with poor survival and reduced responsiveness to chemotherapy in clinical GC specimens. Blocking WNT2 using a specific monoclonal antibody significantly disrupted the WNT2-SOX4 positive feedback loop in GCSCs and enhanced the chemotherapeutic efficacy when synergized with the chemo-drugs 5-fluorouracil and oxaliplatin in a GCSC-derived mouse xenograft model. Overall, this study identified a novel WNT2-SOX4 positive feedback loop as a mechanism for GCSCs-induced chemo-drugs resistance and suggested that the WNT2-SOX4 axis may be a potential therapeutic target for gastric cancer treatment.

7.
Int J Mol Sci ; 24(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175542

RESUMO

Apostasia shenzhenica belongs to the subfamily Apostasioideae and is a primitive group located at the base of the Orchidaceae phylogenetic tree. However, the A. shenzhenica mitochondrial genome (mitogenome) is still unexplored, and the phylogenetic relationships between monocots mitogenomes remain unexplored. In this study, we discussed the genetic diversity of A. shenzhenica and the phylogenetic relationships within its monocotyledon mitogenome. We sequenced and assembled the complete mitogenome of A. shenzhenica, resulting in a circular mitochondrial draft of 672,872 bp, with an average read coverage of 122× and a GC content of 44.4%. A. shenzhenica mitogenome contained 36 protein-coding genes, 16 tRNAs, two rRNAs, and two copies of nad4L. Repeat sequence analysis revealed a large number of medium and small repeats, accounting for 1.28% of the mitogenome sequence. Selection pressure analysis indicated high mitogenome conservation in related species. RNA editing identified 416 sites in the protein-coding region. Furthermore, we found 44 chloroplast genomic DNA fragments that were transferred from the chloroplast to the mitogenome of A. shenzhenica, with five plastid-derived genes remaining intact in the mitogenome. Finally, the phylogenetic analysis of the mitogenomes from A. shenzhenica and 28 other monocots showed that the evolution and classification of most monocots were well determined. These findings enrich the genetic resources of orchids and provide valuable information on the taxonomic classification and molecular evolution of monocots.


Assuntos
Genoma Mitocondrial , Orchidaceae , Filogenia , Mitocôndrias/genética , RNA Ribossômico/genética , Orchidaceae/genética
8.
Int J Biol Sci ; 18(7): 3034-3047, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35541910

RESUMO

5'-Methylthioadenosine phosphorylase (MTAP) is a key enzyme in the methionine salvage pathway and has been reported to suppress tumorigenesis. The MTAP gene is located at 9p21, a chromosome region often deleted in breast cancer (BC). However, the clinical and biological significance of MTAP in BC is still unclear. Here, we reported that MTAP was frequently downregulated in 41% (35/85) of primary BCs and 89% (8/9) of BC cell lines. Low expression of MTAP was significantly correlated with a poor survival of BC patients (P=0.0334). Functional studies showed that MTAP was able to suppress both in vitro and in vivo tumorigenic ability of BC cells, including migration, invasion, angiogenesis, tumor growth and metastasis in nude mice with orthotopic xenograft tumor of BC. Mechanistically, we found that downregulation of MTAP could increase the polyamine levels by activating ornithine decarboxylase (ODC). By treating the MTAP-repressing BC cells with specific ODC inhibitor Difluoromethylornithine (DFMO) or treating the MTAP-overexpressing BC cells with additional putrescine, metastasis-promoting or -suppressing phenotype of these MTAP-manipulated cells was significantly reversed, respectively. Taken together, our data suggested that MTAP has a critical metastasis-suppressive role by tightly regulating ODC activity in BC cells, which may serve as a prominent novel therapeutic target for advanced breast cancer treatment.


Assuntos
Neoplasias da Mama , Ornitina Descarboxilase , Purina-Núcleosídeo Fosforilase , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Regulação para Baixo , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Ornitina Descarboxilase/metabolismo , Purina-Núcleosídeo Fosforilase/genética , Purina-Núcleosídeo Fosforilase/metabolismo
9.
Nat Plants ; 8(4): 373-388, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35449401

RESUMO

To improve our understanding of the origin and evolution of mycoheterotrophic plants, we here present the chromosome-scale genome assemblies of two sibling orchid species: partially mycoheterotrophic Platanthera zijinensis and holomycoheterotrophic Platanthera guangdongensis. Comparative analysis shows that mycoheterotrophy is associated with increased substitution rates and gene loss, and the deletion of most photoreceptor genes and auxin transporter genes might be linked to the unique phenotypes of fully mycoheterotrophic orchids. Conversely, trehalase genes that catalyse the conversion of trehalose into glucose have expanded in most sequenced orchids, in line with the fact that the germination of orchid non-endosperm seeds needs carbohydrates from fungi during the protocorm stage. We further show that the mature plant of P. guangdongensis, different from photosynthetic orchids, keeps expressing trehalase genes to hijack trehalose from fungi. Therefore, we propose that mycoheterotrophy in mature orchids is a continuation of the protocorm stage by sustaining the expression of trehalase genes. Our results shed light on the molecular mechanism underlying initial, partial and full mycoheterotrophy.


Assuntos
Micorrizas , Orchidaceae , Micorrizas/genética , Orchidaceae/genética , Orchidaceae/metabolismo , Orchidaceae/microbiologia , Simbiose , Trealase/metabolismo , Trealose/metabolismo
10.
Gut ; 71(2): 333-344, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33692094

RESUMO

OBJECTIVE: Solid tumours respond poorly to immune checkpoint inhibitor (ICI) therapies. One major therapeutic obstacle is the immunosuppressive tumour microenvironment (TME). Cancer-associated fibroblasts (CAFs) are a key component of the TME and negatively regulate antitumour T-cell response. Here, we aimed to uncover the mechanism underlying CAFs-mediated tumour immune evasion and to develop novel therapeutic strategies targeting CAFs for enhancing ICI efficacy in oesophageal squamous cell carcinoma (OSCC) and colorectal cancer (CRC). DESIGN: Anti-WNT2 monoclonal antibody (mAb) was used to treat immunocompetent C57BL/6 mice bearing subcutaneously grafted mEC25 or CMT93 alone or combined with anti-programmed cell death protein 1 (PD-1), and the antitumour efficiency and immune response were assessed. CAFs-induced suppression of dendritic cell (DC)-differentiation and DC-mediated antitumour immunity were analysed by interfering with CAFs-derived WNT2, either by anti-WNT2 mAb or with short hairpin RNA-mediated knockdown. The molecular mechanism underlying CAFs-induced DC suppression was further explored by RNA-sequencing and western blot analyses. RESULTS: A negative correlation between WNT2+ CAFs and active CD8+ T cells was detected in primary OSCC tumours. Anti-WNT2 mAb significantly restored antitumour T-cell responses within tumours and enhanced the efficacy of anti-PD-1 by increasing active DC in both mouse OSCC and CRC syngeneic tumour models. Directly interfering with CAFs-derived WNT2 restored DC differentiation and DC-mediated antitumour T-cell responses. Mechanistic analyses further demonstrated that CAFs-secreted WNT2 suppresses the DC-mediated antitumour T-cell response via the SOCS3/p-JAK2/p-STAT3 signalling cascades. CONCLUSIONS: CAFs could suppress antitumour immunity through WNT2 secretion. Targeting WNT2 might enhance the ICI efficacy and represent a new anticancer immunotherapy.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Esofágicas/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteína Wnt2/metabolismo , Animais , Linfócitos T CD8-Positivos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células Dendríticas/fisiologia , Modelos Animais de Doenças , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
11.
Chinese Journal of Radiology ; (12): 842-848, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-956739

RESUMO

Objective:To investigate the value of central vein sign (CVS) and iron deposition on quantitative susceptibility imaging (QSM) of 3.0 T MRI in differentiating multiple sclerosis (MS) from neuromyelitis optica spectrum disease (NMOSD).Methods:This study was a retrospective study. A total of 54 MS patients and 49 NMOSD patients were enrolled from July 2018 to December 2020 in People′s Hospital of Leshan and the First Affiliated Hospital of Chongqing Medical University. All patients underwent conventional MRI and three-dimensional enhanced T 2*-weighted angiography (3D-ESWAN), and ESWAN-filtered phase and QSM were reconstructed from 3D-ESWAN data. First, brain lesions of MS and NMOSD were screened on proton density (PD)-T 2WI, and then the location of lesions, CVS and nodular/annular iron deposition were observed on phase and QSM images. The χ 2 test was used to compare the differences in intracranial lesion location, CVS and iron deposition between MS and NMOSD patients. Receiver operating characteristic curve and area under the curve (AUC) were used to assess the efficiency of CVS and QSM iron deposition to differentiate MS from NMOSD. Results:A total of 968 MS lesions were observed in 54 MS patients, of which CVSs were found in 354 lesions and 227 CVSs were located around the lateral ventricles, 117 in deep white matter (DWM) and 10 in the cortex/subcortex; 372 lesions showed nodular iron deposition, and 193 lesions ring iron deposition on QSM. Totally 247 brain lesions were observed in 41 of 48 patients with NMOSD, of which CVSs were found in 4 lesions and 1 located around the lateral ventricle, 3 located in the DWM; 3 lesions showed nodular iron deposition on QSM. There were significant differences in cortex/subcortex lesions, CVS and iron deposition between MS and NMOSD patients (χ 2 were 29.33, 115.66 and 258.21, respectively, all P<0.001). The AUC of CVS for differentiating MS from NMOSD was 0.941 (95%CI 0.887-0.994), with a sensitivity of 96.3% and a specificity of 91.8%; the AUC of iron deposition for differentiating MS from NMOSD was 0.969 (95%CI 0.930-1.000), with a sensitivity of 100% and a specificity of 93.9%. Conclusion:CVS and iron deposition on 3.0 T MRI are distinct radiologic features of MS lesions from those of NMOSD lesions, and have certain value in the differential diagnosis.

12.
Mol Phylogenet Evol ; 164: 107269, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324956

RESUMO

Goodyerinae are one of phylogenetically unresolved groups of Orchidaceae. The lack of resolution achieved through the analyses of previous molecular sequences from one or a few markers has long confounded phylogenetic estimation and generic delimitation. Here, we present large-scale phylogenomic data to compare the plastome structure of the two main clades (Goodyera and Cheirostylis) in this subtribe and further adopt two strategies, combining plastid coding sequences and the whole plastome, to investigate phylogenetic relationships. A total of 46 species in 16 genera were sampled, including 39 species in 15 genera sequenced in this study. The plastomes of heterotrophic species are not drastically reduced in overall size, but display a pattern congruent with a loss of photosynthetic function. The plastomes of autotrophic species ranged from 147 to 165 kb and encoded from 132 to 137 genes. Three unusual structural features were detected: a 1.0-kb inversion in the large single-copy region of Goodyera schlechtendaliana; the loss and/or pseudogenization of ndh genes only in two species, Cheirostylis chinensis and C. montana; and the expansion of inverted repeat regions and contraction of small single-copy region in Hetaeria oblongifolia. Phylogenomic analyses provided improved resolution for phylogenetic relationships. All genera were recovered as monophyletic, except for Goodyera and Hetaeria, which were each recovered as non-monophyletic. Nomenclatural changes are needed until the broader sampling and biparental inherited markers. This study provides a phylogenetic framework of Goodyerinae and insight into plastome evolution of Orchidaceae.


Assuntos
Genomas de Plastídeos , Orchidaceae , Sequência de Bases , Evolução Molecular , Orchidaceae/genética , Filogenia , Plastídeos/genética
13.
Mitochondrial DNA B Resour ; 5(1): 384-385, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33366567

RESUMO

The complete plastid genome of Thrixspermum tsii was determined and analyzed in this work. The plastome was 149,689 bp in length with 86,778 bp of the large single-copy (LSC) region, 12,129 bp of the small single-copy (SSC) region and 25,391 bp of the inverted repeat (IR) regions. The genome contained 120 genes, 74 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis of 17 Aeridinae plastomes suggested four groups were divided, and T. tsii was sister to T. japonicum.

14.
Mitochondrial DNA B Resour ; 5(1): 390-391, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33366570

RESUMO

The complete plastid genome of Holcoglossum singchianum was determined and analyzed in this work. The plastome was 147,715 bp in length with 84,094 bp of the large single-copy (LSC) region, 12,073 bp of the small single-copy (SSC) region and 25,774 bp of the inverted repeat (IRs) regions. The genome contained 120 genes, 74 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis of 20 Aeridinae plastomes suggested three groups of Holcoglossum were divided, and H. singchianum was sister to H. lingulatum.

15.
Insects ; 11(11)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167530

RESUMO

Peroxiredoxins (Prxs), which scavenge reactive oxygen species (ROS), are cysteine-dependent peroxide reductases that group into six structurally discernable classes: AhpC-Prx1, BCP-PrxQ, Prx5, Prx6, Tpx, and AhpE. A previous study showed that forkhead box protein O (FOXO) in the insulin signaling pathway (ISP) plays a vital role in regulating locust diapause by phosphorylation, which can be promoted by the high level of ROS. Furthermore, the analysis of transcriptome between diapause and non-diapause phenotypes showed that one of the Prxs, LmPrx6, which belongs to the Prx6 class, was involved. We presumed that LmPrx6 might play a critical role in diapause induction of Locusta migratoria and LmPrx6 may therefore provide a useful target of control methods based on RNA interference (RNAi). To verify our hypothesis, LmPrx6 was initially cloned from L. migratoria to make dsLmPrx6 and four important targets were tested, including protein-tyrosine phosphorylase 1B (LmPTP1B), insulin receptor (LmIR), RAC serine/threonine-protein kinase (LmAKT), and LmFOXO in ISP. When LmPrx6 was knocked down, the diapause rate was significantly reduced. The phosphorylation level of LmPTP1B significantly decreased while the phosphorylation levels of LmIR, LmAKT, and LmFOXO were significantly increased. Moreover, we identified the effect on two categories of genes downstream of LmFOXO, including stress tolerance and storage of energy reserves. Results showed that the mRNA levels of catalase and Mn superoxide dismutase (Mn-SOD), which enhanced stress tolerance, were significantly downregulated after silencing of LmPrx6. The mRNA levels of glycogen synthase and phosphoenolpyruvate carboxy kinase (PEPCK) that influence energy storage were also downregulated after knocking down of LmPrx6. The silencing of LmPrx6 indicates that this regulatory protein may probably be an ideal target for RNAi-based diapause control of L. migratoria.

16.
Insects ; 11(7)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635501

RESUMO

Oedaleus asiaticus is one of the dominant species of grasshoppers in the rangeland on the Mongolian plateau, and a serious pest, but its migratory behavior is poorly known. We investigated the take-off behavior of migratory O. asiaticus in field cages in the inner Mongolia region of northern China. The species shows a degree of density-dependent phase polyphenism, with high-density swarming populations characterized by a brown morph, while low-density populations are more likely to comprise a green morph. We found that only 12.4% of brown morphs engaged in migratory take-off, and 2.0% of green morphs. Migratory grasshoppers took off at dusk, especially in the half hour after sunset (20:00-20:30 h). Most emigrating individuals did not have any food in their digestive tract, and the females were mated but with immature ovaries. In contrast, non-emigrating individuals rarely had empty digestive tracts, and most females were mated and sexually mature. Therefore, it seems clear that individuals prepare for migration in the afternoon by eliminating food residue from the body, and migration is largely restricted to sexually immature stages (at least in females). Furthermore, it was found that weather conditions (particularly temperature and wind speed at 15:00 h) in the afternoon had a significant effect on take-off that evening, with O. asiaticus preferring to take off in warm, dry and calm weather. The findings of this study will contribute to a reliable basis for forecasting migratory movements of this pest.

17.
Insects ; 11(3)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32164277

RESUMO

We analyzed the transcriptomes of Romalea microptera grasshoppers after 8 years of artificial selection for either long or short thoraces. Evolution proceeded rapidly during the experiment, with a 13.3% increase and a 32.2% decrease in mean pronotum lengths (sexes combined) in the up- and down-selected colonies, respectively, after only 11 generations. At least 16 additional traits also diverged between the two colonies during the selection experiment. Transcriptomic analysis identified 693 differentially expressed genes, with 386 upregulated and 307 downregulated (55.7% vs. 44.3%), including cellular process, metabolic process, binding, general function prediction only, and signal transduction mechanisms. Many of the differentially expressed genes (DEGs) are known to influence animal body size.

18.
Mol Phylogenet Evol ; 145: 106729, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31926307

RESUMO

The Cleisostoma-Gastrochilus clades are among the most speciose and diverse groups of Asian orchids and are a taxonomically problematic group. Phylogenetic relationships among the genera of these clades have remained unresolved with traditional sequences from one or a few markers. We present large-scale phylogenomic data sets, incorporating complete chloroplast genome sequences from 53 species (including 41 species sequenced in this study), to compare plastome structure and to resolve the phylogenetic relationships of these clades. The plastomes of Cleisostoma-Gastrochilus clades possessed the quadripartite structure and plastome genes of typical angiosperms with sizes ranging from 142 to 149 kb and encoding a set of 118-120 genes. Unusual structural features were detected in the plastome of Uncifera acuminata, including the presence of a large 17-kb inversion (19 genes) in the Large Single-Copy region and the loss of the rpl32 gene in Cleisostoma fuerstenbergianum. The pseudogenization of ndh genes was widespread in these clades. Phylogenomic analyses, including 68 plastid protein-coding genes, showed that these clades can be subdivided into three major groupings and six subgroupings: Vandopsis undulata, the Gastrochilus clade (including the Trichoglottis and Gastrochilus subclades) and the Cleisostoma clade (including the Vandopsis, Diploprora, Cleisostoma and Schoenorchis subclades). Two genera, Vandopsis and Cleisostoma, were not monophyletic. A new genus, Cymbilabia, was proposed to avoid non-monophyly of Vandopsis. Our results demonstrate the power of plastid phylogenomics to improve the phylogenetic relationships of intricate groups and provide new insight into plastome evolution in Orchidaceae.


Assuntos
Orchidaceae/classificação , Plastídeos/genética , Evolução Molecular , Funções Verossimilhança , Fases de Leitura Aberta/genética , Orchidaceae/anatomia & histologia , Orchidaceae/genética , Filogenia , Folhas de Planta/genética , RNA Ribossômico/química , RNA Ribossômico/genética , RNA de Transferência/química , RNA de Transferência/genética
19.
Cancer Commun (Lond) ; 39(1): 79, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31771653

RESUMO

Esophageal cancer (EC) seriously threatens human health, and a promising new avenue for EC treatment involves cancer immunotherapy. To improve the efficacy of EC immunotherapy and to develop novel strategies for EC prognosis prediction or clinical treatment, understanding the immune landscapes in EC is required. EC cells harbor abundant tumor antigens, including tumor-associated antigens and neoantigens, which have the ability to initiate dendritic cell-mediated tumor-killing cytotoxic T lymphocytes in the early stage of cancer development. As EC cells battle the immune system, they obtain an ability to suppress antitumor immunity through immune checkpoints, secreted factors, and negative regulatory immune cells. Cancer-associated fibroblasts also contribute to the immune evasion of EC cells. Some factors of the immune landscape in EC tumor microenvironment are associated with cancer development, patient survival, or treatment response. Based on the immune landscape, peptide vaccines, adoptive T cell therapy, and immune checkpoint blockade can be used for EC immunotherapy. Combined strategies are required for better clinical outcome in EC. This review provides directions to design novel and effective strategies for prognosis prediction and immunotherapy in EC.


Assuntos
Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/terapia , Humanos , Imunoterapia , Prognóstico
20.
J Exp Bot ; 70(22): 6611-6619, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31625570

RESUMO

Members of the Orchidaceae, one of the largest families of flowering plants, evolved the crassulacean acid metabolism (CAM) photosynthesis strategy. It is thought that CAM triggers adaptive radiation into new niche spaces, yet very little is known about its origin and diversification on different continents. Here, we assess the prevalence of CAM in Dendrobium, which is one of the largest genera of flowering plants and found in a wide range of environments, from the high altitudes of the Himalayas to relatively arid habitats in Australia. Based on phylogenetic time trees, we estimated that CAM, as determined by δ 13C values less negative than -20.0‰, evolved independently at least eight times in Dendrobium. The oldest lineage appeared in the Asian clade during the middle Miocene, indicating the origin of CAM was associated with a pronounced climatic cooling that followed a period of aridity. Divergence of the four CAM lineages in the Asian clade appeared to be earlier than divergence of those in the Australasian clade. However, CAM species in the Asian clade are much less diverse (25.6%) than those in the Australasian clade (57.9%). These findings shed new light on CAM evolutionary history and the aridity levels of the paleoclimate on different continents.


Assuntos
Evolução Biológica , Ácidos Carboxílicos/metabolismo , Dendrobium/fisiologia , Fotossíntese , Teorema de Bayes , Isótopos de Carbono , Dendrobium/genética , Loci Gênicos , Filogenia
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