Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 119(40): e2123030119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161902

RESUMO

Lorises are a group of globally threatened strepsirrhine primates that exhibit many unusual physiological and behavioral features, including a low metabolic rate, slow movement, and hibernation. Here, we assembled a chromosome-level genome sequence of the pygmy loris (Xanthonycticebus pygmaeus) and resequenced whole genomes from 50 pygmy lorises and 6 Bengal slow lorises (Nycticebus bengalensis). We found that many gene families involved in detoxification have been specifically expanded in the pygmy loris, including the GSTA gene family, with many newly derived copies functioning specifically in the liver. We detected many genes displaying evolutionary convergence between pygmy loris and koala, including PITRM1. Significant decreases in PITRM1 enzymatic activity in these two species may have contributed to their characteristic low rate of metabolism. We also detected many evolutionarily convergent genes and positively selected genes in the pygmy loris that are involved in muscle development. Functional assays demonstrated the decreased ability of one positively selected gene, MYOF, to up-regulate the fast-type muscle fiber, consistent with the lower proportion of fast-twitch muscle fibers in the pygmy loris. The protein product of another positively selected gene in the pygmy loris, PER2, exhibited weaker binding to the key circadian core protein CRY, a finding that may be related to this species' unusual circadian rhythm. Finally, population genomics analysis revealed that these two extant loris species, which coexist in the same habitat, have exhibited an inverse relationship in terms of their demography over the past 1 million years, implying strong interspecies competition after speciation.


Assuntos
Adaptação Biológica , Evolução Biológica , Lorisidae , Adaptação Biológica/genética , Animais , Demografia , Hibernação , Lorisidae/genética , Metagenômica , Metaloendopeptidases/genética
2.
Arch Insect Biochem Physiol ; 110(1): e21877, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35218062

RESUMO

Microplitis bicoloratus bracovirus (MbBV) induces apoptosis in hemocytes of the host (Spodoptera litura) via the cyclophilin A (CypA)-mediated signaling pathway. However, the mechanisms underlying CypA-mediated signaling during apoptosis remain largely unknown. Therefore, in this study, we investigated how CypA and apoptosis-inducing factor (AIF) interact during MbBV-mediated apoptosis. Our findings showed that MbBV induces apoptosis through the CypA-AIF axis of insect immune suppression. In MbBV-infected Spli221 cells, both the expression of the cypa gene and the release of AIF from the mitochondria increased the number of apoptotic cells. CypA and AIF underwent concurrent cytoplasm-nuclear translocation. Conversely, blocking of AIF release from mitochondria not only inhibited the CypA-AIF interaction but also inhibited the cytoplasmic-nuclear translocation of AIF and CypA. Importantly, the survival of the apoptotic phenotype was significantly rescued in MbBV-infected Spli221 cells. In addition, we found that the cyclosporine A-mediated inhibition of CypA did not prevent the formation of the CypA and AIF complex; rather, this only suppressed genomic DNA fragmentation. In vitro experiments revealed direct molecular interactions between recombinant CypA and AIF. Taken together, our results demonstrate that the CypA-AIF interaction plays an important role in MbBV-induced innate immune suppression. This study will help to clarify aspects of insect immunological mechanisms and will be relevant to biological pest control.


Assuntos
Polydnaviridae , Animais , Apoptose , Fator de Indução de Apoptose/metabolismo , Ciclofilina A/genética , Ciclofilina A/metabolismo , Polydnaviridae/fisiologia , Spodoptera/metabolismo
3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936086

RESUMO

Objective: To analyze the association of No.11p posterior lymph node metastasis with clinicopathological features and its prognostic significance in gastric cancer. Methods: A single-center retrospective cohort study was conducted. Clinicopathological data of patients with primary gastric cancers undergoing No.11p posterior lymph node dissection from January 2016 to December 2020 were retrieved from the Database of Gastric Cancer, West China Hospital, Sichuan University. Case inclusion criteria: (1) gastric cancer proved by pathology; (2) radical resection with intraoperative No.11p posterior lymph node dissection; (3) operations performed by the same surgical team; (4) no previous history of other malignant tumors and no concurrent malignant tumors. Those with stump gastric cancer, history of gastrectomy, neoadjuvant chemotherapy, incomplete clinicopathological data and lost to follow-up were excluded. During the operation, the upper edge of the pancreas was retracted forward to expose the area between the upper edge of the pancreas and the splenic vessels. The proximal segment of the splenic artery was skeletonized to remove lymphatic tissue anterior and superior to the splenic artery for No.11p lymph node dissection. For patients with lymphadenopathy in the area between the splenic artery and the splenic vein, dissection was performed. The enlarged lymph nodes were labeled with titanium clips and named as No.11p posterior lymph node. Pathological examination was performed separately after the specimen was isolated. Statistical analysis was performed using R software. Results: A total of 127 gastric cancer patients, who underwent No.11p posterior lymph nodes dissection were included in this study, of which 120 patients without No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes negative) and 7 patients with No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes positive). A total of 8 metastatic No.11p posterior lymph nodes were detected in 7 patients, metastasis rate and with a ratio of 5.5% (7/127) and 6.8% (8/127), respectively. In the subgroup analysis of T3-4 stage patients, the metastasis rate and ratio of No.11p posterior lymph nodes were 9.0% (7/78) and 10.7% (8/75), respectively. Compared to negative cases, patients with No.11p posterior lymph nodes metastasis had larger tumor (P=0.002), higher proportion of Borrmann type Ⅲ and Ⅳ tumors (P=0.005), more metastatic lymph nodes (P<0.001), more advanced T stage (P=0.043), N stage (P=0.004) and TNM stage (P=0.015). In survival analysis, patients with No.11p posterior lymph node metastasis had a significantly worse prognosis than those without metastasis after adjusting for TNM stage (hazard ratio=3.009, 95% confidence interval: 1.824-4.964, P<0.001). Conclusions: The No.11p posterior lymph node metastasis in gastric cancer is associated with worse prognosis. For patients of T3-4 stage gastric cancer, No.11p posterior lymph node dissection should be emphasized during radical operation.


Assuntos
Humanos , Gastrectomia , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática/patologia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia
4.
Genome Biol ; 21(1): 46, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093779

RESUMO

Following publication of the original paper [1], the authors reported an error in the affiliation of Xin-Tian Hu, who is also affiliated with "Kunming Primate Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China".

5.
Mol Biol Evol ; 37(1): 134-148, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31501895

RESUMO

The homing pigeon was selectively bred from the domestic pigeon for a homing ability over long distances, a very fascinating but complex behavioral trait. Here, we generate a total of 95 whole genomes from diverse pigeon breeds. Comparing the genomes from the homing pigeon population with those from other breeds identifies candidate positively selected genes, including many genes involved in the central nervous system, particularly spatial learning and memory such as LRP8. Expression profiling reveals many neuronal genes displaying differential expression in the hippocampus, which is the key organ for memory and navigation and exhibits significantly larger size in the homing pigeon. In addition, we uncover a candidate gene GSR (encoding glutathione-disulfide reductase) experiencing positive selection in the homing pigeon. Expression profiling finds that GSR is highly expressed in the wattle and visual pigment cell layer, and displays increased expression levels in the homing pigeon. In vitro, a magnetic field stimulates increases in calcium ion concentration in cells expressing pigeon GSR. These findings support the importance of the hippocampus (functioning in spatial memory and navigation) for homing ability, and the potential involvement of GSR in pigeon magnetoreception.


Assuntos
Columbidae/genética , Comportamento de Retorno ao Território Vital/fisiologia , Seleção Genética , Animais , Glutationa Redutase/genética , Hipocampo/fisiologia , Memória Espacial
6.
Genome Biol ; 20(1): 258, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779658

RESUMO

BACKGROUND: Brain aging is a complex process that depends on the precise regulation of multiple brain regions; however, the underlying molecular mechanisms behind this process remain to be clarified in non-human primates. RESULTS: Here, we explore non-human primate brain aging using 547 transcriptomes originating from 44 brain areas in rhesus macaques (Macaca mulatta). We show that expression connectivity between pairs of cerebral cortex areas as well as expression symmetry between the left and right hemispheres both decrease after aging. Although the aging mechanisms across different brain areas are largely convergent, changes in gene expression and alternative splicing vary at diverse genes, reinforcing the complex multifactorial basis of aging. Through gene co-expression network analysis, we identify nine modules that exhibit gain of connectivity in the aged brain and uncovered a hub gene, PGLS, underlying brain aging. We further confirm the functional significance of PGLS in mice at the gene transcription, molecular, and behavioral levels. CONCLUSIONS: Taken together, our study provides comprehensive transcriptomes on multiple brain regions in non-human primates and provides novel insights into the molecular mechanism of healthy brain aging.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Hidrolases de Éster Carboxílico/genética , Macaca mulatta/metabolismo , Transcriptoma , Envelhecimento/genética , Animais , Macaca mulatta/genética , Masculino , Camundongos
7.
Artigo em Inglês | MEDLINE | ID: mdl-30623473

RESUMO

Microplitis bicoloratus bracovirus (MbBV) is a polydnavirus found in the parasitic wasp M. bicoloratus. Although MbBV is a known inducer of apoptosis in host hemocytes, the mechanism by which this occurs remains elusive. In this study, we found that expression of cyclophilin A (CypA) was significantly upregulated in Spodoptera litura hemocytes at 6-day post-parasitization. Similar results were reported in High Five cells (Hi5 cells) infected by MbBV, suggesting that the upregulation of CypA is linked to MbBV infection in insect cells. cDNA encoding CypA was cloned from parasitized hemocytes of S. litura, and bioinformatic analyses showed that S. litura CypA belongs to the cyclophilin family of proteins. Overexpression of S. litura CypA in Hi5 cells revealed that the protein promotes MbBV-induced apoptosis in vitro. Conversely, suppression of the expression and activity of CypA protein significantly rescued the apoptotic phenotype observed in MbBV-infected Hi5 cells, suggesting that it plays a key role in this process. MbBV infection also promoted the cytoplasmic-nuclear translocation of CypA in Hi5 cells. Taken together, these results suggest that MbBV infection upregulates the expression of CypA, which is required for MbBV-mediated apoptosis. Our findings provide insight into the role that CypA plays in insect cellular immune response.


Assuntos
Apoptose , Ciclofilina A/genética , Imunidade Celular , Proteínas de Insetos/genética , Polydnaviridae , Spodoptera/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Ciclofilina A/química , Ciclofilina A/metabolismo , Hemócitos/imunologia , Hemócitos/parasitologia , Interações Hospedeiro-Parasita , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/fisiologia , Polydnaviridae/fisiologia , Homologia de Sequência de Aminoácidos , Spodoptera/crescimento & desenvolvimento , Spodoptera/parasitologia , Regulação para Cima , Vespas/crescimento & desenvolvimento , Vespas/fisiologia
8.
Sci Rep ; 7(1): 9174, 2017 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-28835695

RESUMO

Hypoxia is a characteristic of locally advanced solid tumors, resulting from an imbalance between oxygen consumption and supply. In hypoxic solid tumors, an increased expression of nitroreductase (NTR) is detected, therefore, the development of NTR-targeted fluorescent probes to selectively and efficiently detect hypoxia in vivo is of utmost importance. In this study, a probe (1) has been designed and tested for effective optical detection of NTR in vitro and in vivo. The reduction of probe (1), catalyzed by NTR, resulted in changes of the electron-withdrawn nitrogen group into an electron-donation amino group. In addition, breakage of the O-C bond ensured selective fluorescence enhancement. The in vitro response towards exogenous NTR, from rat liver microsomes, resulted in the optical enhancement during the detection process. In vivo imaging of caerorhabditis elegans (C.elegan) further confirmed the detection of NTR by probe (1). Moreover, probe (1) was successfully used for the detection of hypoxia in both HI5 cells, and a murine tumor model, which demonstrates the potential of probe (1) for application in fluorescence bioimaging studies, and tumor hypoxia diagnosis.


Assuntos
Corantes Fluorescentes , Imagem Molecular , Nitrorredutases/metabolismo , Hipóxia Tumoral , Animais , Biomarcadores , Linhagem Celular , Humanos , Imuno-Histoquímica , Camundongos , Microscopia de Fluorescência , Microssomos Hepáticos/metabolismo , Imagem Molecular/métodos , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...