Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
Add more filters










Publication year range
1.
Proc Natl Acad Sci U S A ; 119(40): e2123030119, 2022 10 04.
Article in English | MEDLINE | ID: mdl-36161902

ABSTRACT

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.


Subject(s)
Adaptation, Biological , Biological Evolution , Lorisidae , Adaptation, Biological/genetics , Animals , Demography , Hibernation , Lorisidae/genetics , Metagenomics , Metalloendopeptidases/genetics
2.
Arch Insect Biochem Physiol ; 110(1): e21877, 2022 May.
Article in English | MEDLINE | ID: mdl-35218062

ABSTRACT

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.


Subject(s)
Polydnaviridae , Animals , Apoptosis , Apoptosis Inducing Factor/metabolism , Cyclophilin A/genetics , Cyclophilin A/metabolism , Polydnaviridae/physiology , Spodoptera/metabolism
3.
Nanomicro Lett ; 13(1): 146, 2021 Jun 19.
Article in English | MEDLINE | ID: mdl-34146178

ABSTRACT

Fe-based single-atomic site catalysts (SASCs), with the natural metalloproteases-like active site structure, have attracted widespread attention in biocatalysis and biosensing. Precisely, controlling the isolated single-atom Fe-N-C active site structure is crucial to improve the SASCs' performance. In this work, we use a facile ion-imprinting method (IIM) to synthesize isolated Fe-N-C single-atomic site catalysts (IIM-Fe-SASC). With this method, the ion-imprinting process can precisely control ion at the atomic level and form numerous well-defined single-atomic Fe-N-C sites. The IIM-Fe-SASC shows better peroxidase-like activities than that of non-imprinted references. Due to its excellent properties, IIM-Fe-SASC is an ideal nanoprobe used in the colorimetric biosensing of hydrogen peroxide (H2O2). Using IIM-Fe-SASC as the nanoprobe, in situ detection of H2O2 generated from MDA-MB-231 cells has been successfully demonstrated with satisfactory sensitivity and specificity. This work opens a novel and easy route in designing advanced SASC and provides a sensitive tool for intracellular H2O2 detection.

4.
Small ; 17(16): e2004454, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33306278

ABSTRACT

Carbon-based single-atom catalysts (CSACs) have recently received extensive attention in catalysis research. However, the preparation process of CSACs involves a high-temperature treatment, during which metal atoms are mobile and aggregated into nanoparticles, detrimental to the catalytic performance. Herein, an ion-imprinting derived strategy is proposed to synthesize CSACs, in which isolated metal-nitrogen-carbon (Me-N4 -Cx ) moiety covalently binds oxygen atoms in Si-based molecular sieve frameworks. Such a feature makes Me-N4 -Cx moiety well protected/confined during the heat treatment, resulting in the final material enriched with single-atom metal active sites. As a proof of concept, a single-atom Fe-N-C catalyst is synthesized by using this ion-imprinting derived strategy. Experimental results and theoretical calculations demonstrate high concentration of single FeN4 active sites distributed in this catalyst, resulting in an outstanding oxygen reduction reaction (ORR) performance with a half-wave potential of 0.908 V in alkaline media.

5.
Genome Biol ; 21(1): 46, 2020 Feb 24.
Article in English | MEDLINE | ID: mdl-32093779

ABSTRACT

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".

6.
Mol Biol Evol ; 37(1): 134-148, 2020 Jan 01.
Article in English | MEDLINE | ID: mdl-31501895

ABSTRACT

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.


Subject(s)
Columbidae/genetics , Homing Behavior/physiology , Selection, Genetic , Animals , Glutathione Reductase/genetics , Hippocampus/physiology , Spatial Memory
7.
Genome Biol ; 20(1): 258, 2019 11 28.
Article in English | MEDLINE | ID: mdl-31779658

ABSTRACT

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.


Subject(s)
Aging/metabolism , Brain/metabolism , Carboxylic Ester Hydrolases/genetics , Macaca mulatta/metabolism , Transcriptome , Aging/genetics , Animals , Macaca mulatta/genetics , Male , Mice
8.
Biosens Bioelectron ; 142: 111495, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31310943

ABSTRACT

Due to robustness, easy large-scale preparation and low cost, nanomaterials with enzyme-like characteristics (defined as 'nanozymes') are attracting increasing interest for various applications. However, most of currently developed nanozymes show much lower activity in comparison with natural enzymes, and the deficiency greatly hinders their use in sensing and biomedicine. Single-atom catalysts (SACs) offer the unique feature of maximum atomic utilization, providing a potential pathway to improve the catalytic activity of nanozymes. Herein, we propose a Fe-N-C single-atom nanozyme (SAN) that exhibits unprecedented peroxidase-mimicking activity. The SAN consists of atomically dispersed Fe─Nx moieties hosted by metal-organic frameworks (MOF) derived porous carbon. Thanks to the 100% single-atom active Fe dispersion and the large surface area of the porous support, the Fe-N-C SAN provided a specific activity of 57.76 U mg-1, which was almost at the same level as natural horseradish peroxidase (HRP). Attractively, the SAN presented much better storage stability and robustness against harsh environments. As a proof-of-concept application, highly sensitive biosensing of butyrylcholinesterase (BChE) activity using the Fe-N-C SAN as a substitute for natural HRP was further verified.


Subject(s)
Biomimetic Materials/chemistry , Biosensing Techniques/methods , Butyrylcholinesterase/analysis , Carbon/chemistry , Metal-Organic Frameworks/chemistry , Peroxidase/chemistry , Animals , Catalysis , Horses , Iron/chemistry , Porosity
9.
Article in English | MEDLINE | ID: mdl-30623473

ABSTRACT

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.


Subject(s)
Apoptosis , Cyclophilin A/genetics , Immunity, Cellular , Insect Proteins/genetics , Polydnaviridae , Spodoptera/immunology , Amino Acid Sequence , Animals , Base Sequence , Cyclophilin A/chemistry , Cyclophilin A/metabolism , Hemocytes/immunology , Hemocytes/parasitology , Host-Parasite Interactions , Insect Proteins/chemistry , Insect Proteins/metabolism , Larva/growth & development , Larva/physiology , Polydnaviridae/physiology , Sequence Homology, Amino Acid , Spodoptera/growth & development , Spodoptera/parasitology , Up-Regulation , Wasps/growth & development , Wasps/physiology
10.
Mol Med Rep ; 18(5): 4349-4355, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30221707

ABSTRACT

Angiotensin II (Ang II) is a principal molecule of the renin­angiotensin system, which promotes hypertrophy and fibrosis. It has been demonstrated that Ang II upregulates the expression of cyclophilin A (CypA), which is a potential myocardial hypertrophy factor. However, the mechanisms by which Ang II induces the expression of CypA in cardiomyocytes remain unclear. In the present study, reactive oxygen species (ROS) were detected by fluorescence microscopy, and western blot analysis and ELISA were used to measure CypA expression. It was identified that Ang II enhanced the production of ROS in rat cardiomyocytes. ROS, in turn, promoted CypA expression and secretion. Notably, the action of Ang II was primarily dependent on the angiotensin type 2 receptor (AT2R), not the type 1 receptor. These results provided an insight into the role of the AT2R signaling pathway in Ang II­induced myocardial hypertrophy.


Subject(s)
Angiotensin II/genetics , Cyclophilin A/genetics , Hypertrophy/genetics , Receptor, Angiotensin, Type 2/genetics , Animals , Gene Expression Regulation , Humans , Hypertrophy/pathology , Myocardium/metabolism , Myocardium/pathology , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Rats , Reactive Oxygen Species/metabolism , Receptor, Angiotensin, Type 1/genetics , Signal Transduction
11.
ACS Appl Mater Interfaces ; 9(16): 14309-14318, 2017 Apr 26.
Article in English | MEDLINE | ID: mdl-28394558

ABSTRACT

A facile process is developed to prepare SnO2-based composites through using metal-organic frameworks (MOFs) as precursors. The nitrogen-doped graphene wrapped okra-like SnO2 composites (SnO2@N-RGO) are successfully synthesized for the first time by using Sn-based metal-organic frameworks (Sn-MOF) as precursors. When utilized as an anode material for lithium-ion batteries, the SnO2@N-RGO composites possess a remarkably superior reversible capacity of 1041 mA h g-1 at a constant current of 200 mA g-1 after 180 charge-discharge processes and excellent rate capability. The excellent performance can be primarily ascribed to the unique structure of 1D okra-like SnO2 in SnO2@N-RGO which are actually composed of a great number of SnO2 primary crystallites and numerous well-defined internal voids, can effectively alleviate the huge volume change of SnO2, and facilitate the transport and storage of lithium ions. Besides, the structural stability acquires further improvement when the okra-like SnO2 are wrapped by N-doped graphene. Similarly, this synthetic strategy can be employed to synthesize other high-capacity metal-oxide-based composites starting from various metal-organic frameworks, exhibiting promising application in novel electrode material field of lithium-ion batteries.

SELECTION OF CITATIONS
SEARCH DETAIL
...