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1.
Cell ; 185(16): 2975-2987.e10, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35853453

RESUMO

Horizontal gene transfer (HGT) is an important evolutionary force shaping prokaryotic and eukaryotic genomes. HGT-acquired genes have been sporadically reported in insects, a lineage containing >50% of animals. We systematically examined HGT in 218 high-quality genomes of diverse insects and found that they acquired 1,410 genes exhibiting diverse functions, including many not previously reported, via 741 distinct transfers from non-metazoan donors. Lepidopterans had the highest average number of HGT-acquired genes. HGT-acquired genes containing introns exhibited substantially higher expression levels than genes lacking introns, suggesting that intron gains were likely involved in HGT adaptation. Lastly, we used the CRISPR-Cas9 system to edit the prevalent unreported gene LOC105383139, which was transferred into the last common ancestor of moths and butterflies. In diamondback moths, males lacking LOC105383139 courted females significantly less. We conclude that HGT has been a major contributor to insect adaptation.


Assuntos
Borboletas , Transferência Genética Horizontal , Animais , Borboletas/genética , Corte , Evolução Molecular , Masculino , Filogenia
2.
PLoS Biol ; 22(3): e3002515, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38512963

RESUMO

The signaling environment, or niche, often governs the initial difference in behavior of an adult stem cell and a derivative that initiates a path towards differentiation. The transition between an instructive stem cell niche and differentiation niche must generally have single-cell resolution, suggesting that multiple mechanisms might be necessary to sharpen the transition. Here, we examined the Drosophila ovary and found that Cap cells, which are key constituents of the germline stem cell (GSC) niche, express a conserved microRNA (miR-124). Surprisingly, loss of miR-124 activity in Cap cells leads to a defect in differentiation of GSC derivatives. We present evidence that the direct functional target of miR-124 in Cap cells is the epidermal growth factor receptor (EGFR) and that failure to limit EGFR expression leads to the ectopic expression of a key anti-differentiation BMP signal in neighboring somatic escort cells (ECs), which constitute a differentiation niche. We further found that Notch signaling connects EFGR activity in Cap cells to BMP expression in ECs. We deduce that the stem cell niche communicates with the differentiation niche through a mechanism that begins with the selective expression of a specific microRNA and culminates in the suppression of the major anti-differentiation signal in neighboring cells, with the functionally important overall role of sharpening the spatial distinction between self-renewal and differentiation environments.


Assuntos
Proteínas de Drosophila , MicroRNAs , Animais , Feminino , Drosophila/genética , Drosophila/metabolismo , Ovário/metabolismo , Proteínas de Drosophila/metabolismo , Nicho de Células-Tronco/genética , Diferenciação Celular/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Células-Tronco/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Comunicação , Drosophila melanogaster/metabolismo , Células Germinativas/metabolismo
3.
PLoS Biol ; 21(7): e3002197, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37410725

RESUMO

Drosophila melanogaster Down syndrome cell adhesion molecule 1 (Dscam1) encodes 19,008 diverse ectodomain isoforms via the alternative splicing of exon 4, 6, and 9 clusters. However, whether individual isoforms or exon clusters have specific significance is unclear. Here, using phenotype-diversity correlation analysis, we reveal the redundant and specific roles of Dscam1 diversity in neuronal wiring. A series of deletion mutations were performed from the endogenous locus harboring exon 4, 6, or 9 clusters, reducing to 396 to 18,612 potential ectodomain isoforms. Of the 3 types of neurons assessed, dendrite self/non-self discrimination required a minimum number of isoforms (approximately 2,000), independent of exon clusters or isoforms. In contrast, normal axon patterning in the mushroom body and mechanosensory neurons requires many more isoforms that tend to associate with specific exon clusters or isoforms. We conclude that the role of the Dscam1 diversity in dendrite self/non-self discrimination is nonspecifically mediated by its isoform diversity. In contrast, a separate role requires variable domain- or isoform-related functions and is essential for other neurodevelopmental contexts, such as axonal growth and branching. Our findings shed new light on a general principle for the role of Dscam1 diversity in neuronal wiring.


Assuntos
Síndrome de Down , Proteínas de Drosophila , Animais , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Molécula 1 de Adesão Celular/genética , Molécula 1 de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Síndrome de Down/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Neurônios/metabolismo
4.
Nature ; 578(7794): 290-295, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32025034

RESUMO

Shear stress on arteries produced by blood flow is important for vascular development and homeostasis but can also initiate atherosclerosis1. Endothelial cells that line the vasculature use molecular mechanosensors to directly detect shear stress profiles that will ultimately lead to atheroprotective or atherogenic responses2. Plexins are key cell-surface receptors of the semaphorin family of cell-guidance signalling proteins and can regulate cellular patterning by modulating the cytoskeleton and focal adhesion structures3-5. However, a role for plexin proteins in mechanotransduction has not been examined. Here we show that plexin D1 (PLXND1) has a role in mechanosensation and mechanically induced disease pathogenesis. PLXND1 is required for the response of endothelial cells to shear stress in vitro and in vivo and regulates the site-specific distribution of atherosclerotic lesions. In endothelial cells, PLXND1 is a direct force sensor and forms a mechanocomplex with neuropilin-1 and VEGFR2 that is necessary and sufficient for conferring mechanosensitivity upstream of the junctional complex and integrins. PLXND1 achieves its binary functions as either a ligand or a force receptor by adopting two distinct molecular conformations. Our results establish a previously undescribed mechanosensor in endothelial cells that regulates cardiovascular pathophysiology, and provide a mechanism by which a single receptor can exhibit a binary biochemical nature.


Assuntos
Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mecanotransdução Celular , Glicoproteínas de Membrana/metabolismo , Estresse Mecânico , Animais , Aterosclerose/metabolismo , Feminino , Integrinas/metabolismo , Camundongos , Neuropilina-1/metabolismo , Maleabilidade , Receptores de Superfície Celular/metabolismo , Semaforinas/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
5.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38061001

RESUMO

Parasitoids introduce various virulence factors when parasitism occurs, and some taxa generate teratocytes to manipulate the host immune system and metabolic homeostasis for the survival and development of their progeny. Host-parasitoid interactions are extremely diverse and complex, yet the evolutionary dynamics are still poorly understood. A category of serpin genes, named CvT-serpins, was discovered to be specifically expressed and secreted by the teratocytes of Cotesia vestalis, an endoparasitoid of the diamondback moth Plutella xylostella. Genomic and phylogenetic analysis indicated that the C. vestalis serpin genes are duplicated and most of them are clustered into 1 monophyletic clade. Intense positive selection was detected at the residues around the P1-P1' cleavage sites of the Cv-serpin reactive center loop domain. Functional analyses revealed that, in addition to the conserved function of melanization inhibition (CvT-serpins 1, 16, 18, and 21), CvT-serpins exhibited novel functions, i.e. bacteriostasis (CvT-serpins 3 and 5) and nutrient metabolism regulation (CvT-serpins 8 and 10). When the host-parasitoid system is challenged with foreign bacteria, CvT-serpins act as an immune regulator to reprogram the host immune system through sustained inhibition of host melanization while simultaneously functioning as immune effectors to compensate for this suppression. In addition, we provided evidence that CvT-serpin8 and 10 participate in the regulation of host trehalose and lipid levels by affecting genes involved in these metabolic pathways. These findings illustrate an exquisite tactic by which parasitoids win out in the parasite-host evolutionary arms race by manipulating host immune and nutrition homeostasis via adaptive gene evolution and neofunctionalization.


Assuntos
Mariposas , Parasitos , Serpinas , Vespas , Animais , Serpinas/genética , Filogenia , Mariposas/genética , Homeostase , Larva/metabolismo , Vespas/genética
6.
Small ; 20(38): e2401596, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38889398

RESUMO

All inorganic lead halide perovskites exhibit fascinating optical and optoelectronic characteristics for on-chip lasing, but the lack of precise control of wafer-scale fabrication for perovskite microstructure arrays restricts their potential applications in on-chip-integrated devices. In this work, a microstructure-template assisted crystallization method is demonstrated via a designed chemical vapor deposition process, achieving the controllable fabrication of homogeneous perovskite micro-hemispheroid (PeMH) arrays spanning the entire surface area of a 4-inch wafer. Benefiting from the low-loss whispering gallery resonance and plasmon-enhanced light-matter interactions in well-confined hybrid cavities, this CsPbX3/Ag (X = Cl, Br) plasmonic microlasers exhibit quite low thresholds below 10 µJ cm-2. Interestingly, these thresholds can be efficiently modulated through the manipulation of plasmonic resonance and electromagnetic field mode in PeMHs owning various diameters. This strategy not only provides a valuable methodology for the large-scale fabrication of perovskite microstructures but also endorses the potential of all-inorganic perovskite nanostructures as promising candidates for on-chip-integrated light sources.

7.
Exp Dermatol ; 33(5): e15094, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38742793

RESUMO

Melasma is a common condition of hyperpigmented facial skin. Picosecond lasers are reported to be effective for the treatment of melasma. We aimed to identify the most effective therapeutic mode and elucidate the potential molecular mechanisms of picosecond lasers for the treatment of melasma. Female Kunming mice with melasma-like conditions were treated using four different picosecond laser modes. Concurrently, in vitro experiments were conducted to assess changes in melanin and autophagy in mouse melanoma B16-F10 cells treated with these laser modes. Changes in melanin in mouse skin were detected via Fontana-Masson staining, and melanin particles were evaluated in B16-F10 cells. Real-time polymerase chain reaction and western blotting were used to analyse the expression levels of melanosome and autophagy-related messenger ribonucleic acid (mRNA) and proteins. A combination of large-spot low-fluence 1064-nm and fractional 1064-nm picosecond lasers resulted insignificant decreases in melanin as well as in mRNA and protein expression of melanin-synthesizing enzymes (TYR, TRP-1 and MITF). This combination also led to increased expression of the autophagy-related proteins, Beclin1 and ATG5, with a marked decrease in p62 expression. Intervention with the PI3K activator, 740 Y-P, increased TYR, TRP-1, MITF, p-PI3K, p-AKT, p-mTOR and p62 expression but decreased the expression of LC3, ATG5 and Beclin1. A combination of large-spot low-fluence 1064-nm and fractional 1064-nm picosecond lasers proved more effective and safer. It inhibits melanin production, downregulates the PI3K/AKT/mTOR pathway, enhances melanocyte autophagy and accelerates melanin metabolism, thereby reducing melanin content.


Assuntos
Autofagia , Melanose , Melanossomas , Transdução de Sinais , Animais , Feminino , Camundongos , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Terapia com Luz de Baixa Intensidade , Melaninas/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/radioterapia , Melanose/metabolismo , Melanossomas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
8.
Chemistry ; 30(53): e202402023, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032086

RESUMO

This study presents the design, synthesis, and comprehensive characterization of a novel series of D-π-A type malononitrile-derived chromophores, BTC-1-BTC-4. Combining various spectroscopic techniques, nonlinear Z-scan measurements, and quantum chemical calculations, we revealed the intricate relationship between nonlinear optical properties and the interplay of molecular structure, intramolecular charge transfer (ICT), and dipole moments (µ). Our experimental and computational findings corroborate that the polarization degree in the ground state, the charge separation in the excited state and twisted intramolecular charge transfer (TICT) collectively dictate the nonlinear optical properties of the compounds. Notably, BTC-1 exhibits an exceptional nonlinear absorption coefficient ß value (2×10-8 m W-1), attributed to its optimized charge transfer efficiency and pronounced degree of charge separation. Our findings provide actionable insights for the rational design of high-performance organic Nonlinear optics (NLO) materials with potential applications in advanced photonic devices.

9.
Langmuir ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422278

RESUMO

For substrate-supported polymer films, the tails of adsorbed chains are generally assumed to play important roles in the propagation of the substrate's effect inside polymer films. The effects of the grafting density and the rigidity of substrate-grafted polymers, the simplest model for the adsorbed tails, on the diffusivity of film polymers are investigated by performing molecular dynamics simulations. An optimal grafting density σo, around the critical grafting density for the transition from "mushroom" to "brush", is found with the most pronounced suppression of diffusivity on the film polymers; i.e., the penetration of the film polymers into the grafting layer reaches the maximum. However, at high grafting density, the crowded and vertically stretched brush excludes the coil-like film polymers, and the suppression is thus reduced. At σo, with an increase in the rigidity of the grafted polymers, the suppression is increased quickly at low rigidity but slowly at high rigidity. The dynamic suppression is attributed to the combination of the conformation change from stretching at low rigidity to tilted orientation at high rigidity and decelerated mobility induced by the rigidity. The stretching conformation enhances, whereas the tilted conformation weakens the interpenetration between the grafted polymers and the film polymers. Our results reflect the importance of both conformational variation and interchain interaction in the interface region.

10.
Macromol Rapid Commun ; 45(16): e2400189, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38748845

RESUMO

Conjugated polymers with integrating properties of delayed fluorescence and photovoltaic responses simultaneously are scarcely reported due to the generally contradictory requirements for molecular structures to achieve the two properties. Herein, an O-B(F)←N functionalized fused unit (M) with multiple resonance features, small energy gap between lowest singlet excited state (S1) and triplet excited state (T1) (ΔEST = 0.23 eV), and delayed fluorescence (τD = 0.75 µs), is designed. Selecting three benzodithiophene (BDT) derivatives as co-units to copolymerize with M, leading to a series of O-B(F)←N embedded polymers also maintaining delayed fluorescence (τD = 0.4-0.5 µs). Moreover, p-type semiconductor characteristics are tested for these polymers with hole mobilities in the range of 10-6-10-5 cm2/Vs. Devices with obviously photovoltaic responses are prepared using these polymers as donors and Y6 as the acceptor, affording a preliminary efficiency of 5.05%. This work successfully demonstrates an effective strategy to design conjugated polymers with integrating properties of delayed fluorescence and photovoltaic performance simultaneously by introducing O-B(F)←N functional groups to polymer backbones.


Assuntos
Polímeros , Semicondutores , Polímeros/química , Polímeros/síntese química , Fluorescência , Estrutura Molecular
11.
Ann Vasc Surg ; 104: 315-323, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38599492

RESUMO

BACKGROUND: The Talos stent-graft has extended length to improve aortic remodeling, and distal porous design to decrease the rate of spinal cord ischemia (SCI). This study retrospectively analyzed its mid-term outcomes for uncomplicated type B aortic dissection in a multicenter study. METHODS: The primary safety end point was 30-day major adverse events, including all-cause mortality, dissection-related mortality, conversion to open surgery, and device-related adverse events. The primary efficacy end point was treatment success at 12 months postoperation, defined as no technical failure or secondary dissection-related reintervention. The survival status of the patients was visualized using the Kaplan-Meier curve. Aortic growth was assessed at 4 levels, and SCI was evaluated at 12 months. RESULTS: 113 patients participated with a mean age of 54.4 (11.1) years and 71.7% (81/113) were male. The 30-day mortality was 0.9% (1/113), no conversions to open surgery or device-related adverse events were recorded. The 12-month treatment success rate was 99.1% (112/113), with no dissection-related reinterventions. There was no spinal cord or visceral ischemia at 12 months. At a median of 34 months follow-up, 9 further deaths were recorded and the 3-year survival rate was 91.7%. The percentage of aortic growth was 1.8% (2/111) at the tracheal bifurcation, 3.6% (4/111) below the left atrium, 6.0% (5/83) above the celiac artery, and 12.1% (9/74) below the lower renal artery. The total thrombosis rate of the false lumen at the stented segment was 80.5% (91/113). CONCLUSIONS: The results showed satisfactory results of Talos stent-graft in terms of safety and efficacy. More data are needed to confirm the long-term performance.


Assuntos
Dissecção Aórtica , Implante de Prótese Vascular , Prótese Vascular , Procedimentos Endovasculares , Desenho de Prótese , Stents , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Dissecção Aórtica/cirurgia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Estudos Retrospectivos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Resultado do Tratamento , Fatores de Tempo , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Adulto , Idoso , Fatores de Risco , Porosidade , Aneurisma Aórtico/cirurgia , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/mortalidade , Complicações Pós-Operatórias/etiologia , Japão
12.
PLoS Genet ; 17(9): e1009751, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34492000

RESUMO

Some DNA viruses infect host animals usually by integrating their DNAs into the host genome. However, the mechanisms for integration remain largely unknown. Here, we find that Cotesia vestalis bracovirus (CvBV), a polydnavirus of the parasitic wasp C. vestalis (Haliday), integrates its DNA circles into host Plutella xylostella (L.) genome by two distinct strategies, conservatively and randomly, through high-throughput sequencing analysis. We confirmed that the conservatively integrating circles contain an essential "8+5" nucleotides motif which is required for integration. Then we find CvBV circles are integrated into the caterpillar's genome in three temporal patterns, the early, mid and late stage-integration. We further identify that three CvBV-encoded integrases are responsible for some, but not all of the virus circle integrations, indeed they mainly participate in the processes of early stage-integration. Strikingly, we find two P. xylostella retroviral integrases (PxIN1 and PxIN2) are highly induced upon wasp parasitism, and PxIN1 is crucial for integration of some other early-integrated CvBV circles, such as CvBV_04, CvBV_12 and CvBV_24, while PxIN2 is important for integration of a late-integrated CvBV circle, CvBV_21. Our data uncover a novel mechanism in which CvBV integrates into the infected host genome, not only by utilizing its own integrases, but also by recruiting host enzymes. These findings will strongly deepen our understanding of how bracoviruses regulate and integrate into their hosts.


Assuntos
DNA Viral/genética , Integrases/metabolismo , Mariposas/genética , Polydnaviridae/fisiologia , Animais , Interações Hospedeiro-Parasita/genética , Mariposas/enzimologia , Mariposas/parasitologia , Polydnaviridae/genética , Vespas/genética , Vespas/fisiologia
13.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34544864

RESUMO

It is well documented that the juvenile hormone (JH) can function as a gonadotropic hormone that stimulates vitellogenesis by activating the production and uptake of vitellogenin in insects. Here, we describe a phenotype associated with mutations in the Drosophila JH receptor genes, Met and Gce: the accumulation of mature eggs with reduced egg length in the ovary. JH signaling is mainly activated in ovarian muscle cells and induces laminin gene expression in these cells. Meanwhile, JH signaling induces collagen IV gene expression in the adult fat body, from which collagen IV is secreted and deposited onto the ovarian muscles. Laminin locally and collagen IV remotely contribute to the assembly of ovarian muscle extracellular matrix (ECM); moreover, the ECM components are indispensable for ovarian muscle contraction. Furthermore, ovarian muscle contraction externally generates a mechanical force to promote ovulation and maintain egg shape. This work reveals an important mechanism for JH-regulated insect reproduction.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Hormônios Juvenis/farmacologia , Oócitos/citologia , Oogênese , Ovulação , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster , Matriz Extracelular/efeitos dos fármacos , Proteínas da Matriz Extracelular/genética , Feminino , Laminina/genética , Laminina/metabolismo , Mutação , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Fatores de Transcrição/genética , Vitelogênese , Vitelogeninas/metabolismo
14.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34782465

RESUMO

Ischemic stroke can induce neurogenesis. However, most stroke-generated newborn neurons cannot survive. It has been shown that MR-409, a potent synthetic agonistic analog of growth hormone-releasing hormone (GHRH), can protect against some life-threatening pathological conditions by promoting cell proliferation and survival. The present study shows that long-term treatment with MR-409 (5 or 10 µg/mouse/d) by subcutaneous (s.c.) injection significantly reduces the mortality, ischemic insult, and hippocampal atrophy, and improves neurological functional recovery in mice operated on for transient middle cerebral artery occlusion (tMCAO). Besides, MR-409 can stimulate endogenous neurogenesis and improve the tMCAO-induced loss of neuroplasticity. MR-409 also enhances the proliferation and inhibits apoptosis of neural stem cells treated with oxygen and glucose deprivation-reperfusion. The neuroprotective effects of MR-409 are closely related to the activation of AKT/CREB and BDNF/TrkB pathways. In conclusion, the present study demonstrates that GHRH agonist MR-409 has remarkable neuroprotective effects through enhancing endogenous neurogenesis in cerebral ischemic mice.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/agonistas , Hormônio Liberador de Hormônio do Crescimento/metabolismo , AVC Isquêmico/metabolismo , Regeneração Nervosa/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hormônio Liberador de Hormônio do Crescimento/genética , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Plasticidade Neuronal , Fármacos Neuroprotetores , Proteínas Tirosina Quinases/metabolismo , Recuperação de Função Fisiológica/efeitos dos fármacos
15.
BMC Biol ; 21(1): 143, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340484

RESUMO

BACKGROUND: How stem cell populations are organized and regulated within adult tissues is important for understanding cancer origins and for developing cell replacement strategies. Paradigms such as mammalian gut stem cells and Drosophila ovarian follicle stem cells (FSC) are characterized by population asymmetry, in which stem cell division and differentiation are separately regulated processes. These stem cells behave stochastically regarding their contributions to derivative cells and also exhibit dynamic spatial heterogeneity. Drosophila FSCs provide an excellent model for understanding how a community of active stem cells maintained by population asymmetry is regulated. Here, we use single-cell RNA sequencing to profile the gene expression patterns of FSCs and their immediate derivatives to investigate heterogeneity within the stem cell population and changes associated with differentiation. RESULTS: We describe single-cell RNA sequencing studies of a pre-sorted population of cells that include FSCs and the neighboring cell types, escort cells (ECs) and follicle cells (FCs), which they support. Cell-type assignment relies on anterior-posterior (AP) location within the germarium. We clarify the previously determined location of FSCs and use spatially targeted lineage studies as further confirmation. The scRNA profiles among four clusters are consistent with an AP progression from anterior ECs through posterior ECs and then FSCs, to early FCs. The relative proportion of EC and FSC clusters are in good agreement with the prevalence of those cell types in a germarium. Several genes with graded profiles from ECs to FCs are highlighted as candidate effectors of the inverse gradients of the two principal signaling pathways, Wnt and JAK-STAT, that guide FSC differentiation and division. CONCLUSIONS: Our data establishes an important resource of scRNA-seq profiles for FSCs and their immediate derivatives that is based on precise spatial location and functionally established stem cell identity, and facilitates future genetic investigation of regulatory interactions guiding FSC behavior.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Feminino , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Diferenciação Celular/genética , Folículo Ovariano , Células-Tronco/metabolismo , Mamíferos
16.
Genomics ; 115(2): 110557, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36610559

RESUMO

Early bolting of Peucedanum praeruptorum Dunn severely affects its quality. In this study, we compared with the root structure of P. praeruptorum and its four coumarins content between early bolting (CT) and unbolting (WT) at different growth stages. We found that the proportion of area outside the root cambium (Rs) was higher in the WT plants than in the CT plants and correlated positively with the proximity to the root tip. Furthermore, the content of all four coumarins was also higher in the WT plants relative to the CT plants. In addition, we identified 15,524 differentially expressed genes (DEGs) between the two plant varieties. 11 DEGs are involved in the photoperiod and gibberellin pathways that regulate early bolting and 24 genes involved in coumarins biosynthesis were also identified. Nevertheless, early bolting of P. praeruptorum does affect its quality formation, and further studies are needed to confirm its mechanism.


Assuntos
Apiaceae , Cumarínicos , Cumarínicos/química , Apiaceae/genética , Apiaceae/química , Apiaceae/metabolismo
17.
Environ Microbiol ; 25(3): 642-645, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36511824

RESUMO

As the most diverse group of animals on Earth, insects are key organisms in ecosystems. Horizontal gene transfer (HGT) refers to the transfer of genetic material between species by non-reproductive means. HGT is a major evolutionary force in prokaryotic genome evolution, but its importance in different eukaryotic groups, such as insects, has only recently begun to be understood. Genomic data from hundreds of insect species have enabled the detection of large numbers of HGT events and the elucidation of the functions of some of these foreign genes. Although quantification of the extent of HGT in insects broadens our understanding of its role in insect evolution, the scope of its influence and underlying mechanism(s) of its occurrence remain open questions for the field.


Assuntos
Evolução Molecular , Transferência Genética Horizontal , Animais , Ecossistema , Células Procarióticas , Insetos , Genoma de Inseto , Filogenia
18.
J Transl Med ; 21(1): 277, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095548

RESUMO

BACKGROUND: Icariin (ICA), an active ingredient extracted from Epimedium species, has shown promising results in the treatment of Alzheimer's disease (AD), although its potential therapeutic mechanism remains largely unknown. This study aimed to investigate the therapeutic effects and the underlying mechanisms of ICA on AD by an integrated analysis of gut microbiota, metabolomics, and network pharmacology (NP). METHODS: The cognitive impairment of mice was measured using the Morris Water Maze test and the pathological changes were assessed using hematoxylin and eosin staining. 16S rRNA sequencing and multi-metabolomics were performed to analyze the alterations in the gut microbiota and fecal/serum metabolism. Meanwhile, NP was used to determine the putative molecular regulation mechanism of ICA in AD treatment. RESULTS: Our results revealed that ICA intervention significantly improved cognitive dysfunction in APP/PS1 mice and typical AD pathologies in the hippocampus of the APP/PS1 mice. Moreover, the gut microbiota analysis showed that ICA administration reversed AD-induced gut microbiota dysbiosis in APP/PS1 mice by elevating the abundance of Akkermansia and reducing the abundance of Alistipe. Furthermore, the metabolomic analysis revealed that ICA reversed the AD-induced metabolic disorder via regulating the glycerophospholipid and sphingolipid metabolism, and correlation analysis revealed that glycerophospholipid and sphingolipid were closely related to Alistipe and Akkermansia. Moreover, NP indicated that ICA might regulate the sphingolipid signaling pathway via the PRKCA/TNF/TP53/AKT1/RELA/NFKB1 axis for the treatment of AD. CONCLUSION: These findings indicated that ICA may serve as a promising therapeutic approach for AD and that the ICA-mediated protective effects were associated with the amelioration of microbiota disturbance and metabolic disorder.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Camundongos , Animais , Farmacologia em Rede , RNA Ribossômico 16S , Camundongos Transgênicos
19.
PLoS Pathog ; 17(3): e1009365, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33647060

RESUMO

Parasites alter host energy homeostasis for their own development, but the mechanisms underlying this phenomenon remain largely unknown. Here, we show that Cotesia vestalis, an endoparasitic wasp of Plutella xylostella larvae, stimulates a reduction of host lipid levels. This process requires excess secretion of P. xylostella tachykinin (PxTK) peptides from enteroendocrine cells (EEs) in the midgut of the parasitized host larvae. We found that parasitization upregulates PxTK signaling to suppress lipogenesis in midgut enterocytes (ECs) in a non-cell-autonomous manner, and the reduced host lipid level benefits the development of wasp offspring and their subsequent parasitic ability. We further found that a C. vestalis bracovirus (CvBV) gene, CvBV 9-2, is responsible for PxTK induction, which in turn reduces the systemic lipid level of the host. Taken together, these findings illustrate a novel mechanism for parasite manipulation of host energy homeostasis by a symbiotic bracovirus gene to promote the development and increase the parasitic efficiency of an agriculturally important wasp species.


Assuntos
Interações Hospedeiro-Parasita/imunologia , Metabolismo dos Lipídeos/fisiologia , Parasitos/virologia , Polydnaviridae/genética , Animais , Sistema Digestório/metabolismo , Interações Hospedeiro-Parasita/genética , Larva/metabolismo , Larva/virologia , Metabolismo dos Lipídeos/imunologia , Parasitos/patogenicidade , Polydnaviridae/patogenicidade , Transdução de Sinais/imunologia , Transdução de Sinais/fisiologia , Vespas/fisiologia , Vespas/virologia
20.
Fish Shellfish Immunol ; 139: 108926, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37406893

RESUMO

The greasyback shrimp, Metapenaeus ensis, suffers from ammonia-N stress during intensive factory aquaculture. Optimizing ammonia-N stress tolerance has become an important issue in M. ensis breeding. The metabolic and adaptive mechanisms of ammonia-N toxicity in M. ensis have not been comprehensively understood yet. In this study, a large number of potential simple sequence repeats (SSRs) in the transcriptome of M. ensis were identified. Differentially expressed genes (DEGs) in the gill and hepatopancreas at 24 h post-challenges under high concentrations of ammonia-N treatment were detected. We obtained 20,108,851-27,681,918 clean reads from the control and high groups, assembled and clustered a total of 103,174 unigenes with an average of 876 bp and an N50 of 1189 bp. Comparative transcriptome analyses identified 2000 different expressed genes in the gill and 2010 different expressed genes in the hepatopancreas, a large number of which were related to immune function, oxidative stress, metabolic regulation, and apoptosis. The results suggest that M. ensis may counteract ammonia-N toxicity at the transcriptome level by increasing the expression of genes related to immune stress and detoxification metabolism, and that selected genes may serve as molecular indicators of ammonia-N. By exploring the genetic basis of M. ensis' ammonia-N stress adaptation, we constructed the genetic networks for ammonia-N adaptation. These findings will accelerate the understanding of M. ensis' ammonia-N adaptation, contribute to the research of future breeding, and promote the level of factory aquaculture of M. ensis.


Assuntos
Penaeidae , Animais , Amônia/toxicidade , Amônia/metabolismo , Brânquias , Perfilação da Expressão Gênica , Transcriptoma
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