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1.
Nature ; 629(8012): 579-585, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750235

RESUMO

Towards realizing the future quantum internet1,2, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive multi-node set-ups on large scales. Here we report the creation of memory-memory entanglement in a multi-node quantum network over a metropolitan area. We use three independent memory nodes, each of which is equipped with an atomic ensemble quantum memory3 that has telecom conversion, together with a photonic server where detection of a single photon heralds the success of entanglement generation. The memory nodes are maximally separated apart for 12.5 kilometres. We actively stabilize the phase variance owing to fibre links and control lasers. We demonstrate concurrent entanglement generation between any two memory nodes. The memory lifetime is longer than the round-trip communication time. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a stage of quantum internet research.

2.
Nature ; 589(7841): 214-219, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408416

RESUMO

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Mol Cell ; 73(4): 788-802.e7, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30704899

RESUMO

mTORC1 and GSK3 play critical roles in early stages of (macro)autophagy, but how they regulate late steps of autophagy remains poorly understood. Here we show that mTORC1 and GSK3-TIP60 signaling converge to modulate autophagosome maturation through Pacer, an autophagy regulator that was identified in our recent study. Hepatocyte-specific Pacer knockout in mice results in impaired autophagy flux, glycogen and lipid accumulation, and liver fibrosis. Under nutrient-rich conditions, mTORC1 phosphorylates Pacer at serine157 to disrupt the association of Pacer with Stx17 and the HOPS complex and thus abolishes Pacer-mediated autophagosome maturation. Importantly, dephosphorylation of Pacer under nutrient-deprived conditions promotes TIP60-mediated Pacer acetylation, which facilitates HOPS complex recruitment and is required for autophagosome maturation and lipid droplet clearance. This work not only identifies Pacer as a regulator in hepatic autophagy and liver homeostasis in vivo but also reveals a signal integration mechanism involved in late stages of autophagy and lipid metabolism.


Assuntos
Autofagossomos/enzimologia , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Quinase 3 da Glicogênio Sintase/metabolismo , Metabolismo dos Lipídeos , Fígado/enzimologia , Lisina Acetiltransferase 5/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Transativadores/metabolismo , Acetilação , Animais , Autofagossomos/patologia , Proteínas Relacionadas à Autofagia/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Quinase 3 da Glicogênio Sintase/genética , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Gotículas Lipídicas/metabolismo , Fígado/patologia , Lisina Acetiltransferase 5/genética , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Ligação a Fosfato/genética , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Transdução de Sinais , Transativadores/genética , Proteínas Supressoras de Tumor
4.
Am J Hum Genet ; 110(3): 487-498, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36809768

RESUMO

Genome-wide association studies (GWASs) have established the contribution of common and low-frequency variants to metabolic blood measurements in the UK Biobank (UKB). To complement existing GWAS findings, we assessed the contribution of rare protein-coding variants in relation to 355 metabolic blood measurements-including 325 predominantly lipid-related nuclear magnetic resonance (NMR)-derived blood metabolite measurements (Nightingale Health Plc) and 30 clinical blood biomarkers-using 412,393 exome sequences from four genetically diverse ancestries in the UKB. Gene-level collapsing analyses were conducted to evaluate a diverse range of rare-variant architectures for the metabolic blood measurements. Altogether, we identified significant associations (p < 1 × 10-8) for 205 distinct genes that involved 1,968 significant relationships for the Nightingale blood metabolite measurements and 331 for the clinical blood biomarkers. These include associations for rare non-synonymous variants in PLIN1 and CREB3L3 with lipid metabolite measurements and SYT7 with creatinine, among others, which may not only provide insights into novel biology but also deepen our understanding of established disease mechanisms. Of the study-wide significant clinical biomarker associations, 40% were not previously detected on analyzing coding variants in a GWAS in the same cohort, reinforcing the importance of studying rare variation to fully understand the genetic architecture of metabolic blood measurements.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Bancos de Espécimes Biológicos , Biomarcadores , Lipídeos , Reino Unido , Polimorfismo de Nucleotídeo Único
5.
Proc Natl Acad Sci U S A ; 120(16): e2213512120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37036994

RESUMO

Some tropical sea cucumbers of the family Holothuriidae can efficiently repel or even fatally ensnare predators by sacrificially ejecting a bioadhesive matrix termed the Cuvierian organ (CO), so named by the French zoologist Georges Cuvier who first described it in 1831. Still, the precise mechanisms for how adhesiveness genetically arose in CO and how sea cucumbers perceive and transduce danger signals for CO expulsion during defense have remained unclear. Here, we report the first high-quality, chromosome-level genome assembly of Holothuria leucospilota, an ecologically significant sea cucumber with prototypical CO. The H. leucospilota genome reveals characteristic long-repeat signatures in CO-specific outer-layer proteins, analogous to fibrous proteins of disparate species origins, including spider spidroin and silkworm fibroin. Intriguingly, several CO-specific proteins occur with amyloid-like patterns featuring extensive intramolecular cross-ß structures readily stainable by amyloid indicator dyes. Distinct proteins within the CO connective tissue and outer surface cooperate to give the expelled matrix its apparent tenacity and adhesiveness, respectively. Genomic evidence offers further hints that H. leucospilota directly transduces predator-induced mechanical pressure onto the CO surface through mediation by transient receptor potential channels, which culminates in acetylcholine-triggered CO expulsion in part or in entirety. Evolutionarily, innovative events in two distinct regions of the H. leucospilota genome have apparently spurred CO's differentiation from the respiratory tree to a lethal defensive organ against predators.


Assuntos
Holothuria , Pepinos-do-Mar , Animais , Holothuria/genética , Holothuria/química , Holothuria/metabolismo , Proteínas Amiloidogênicas/metabolismo , Adesividade
6.
PLoS Pathog ; 19(8): e1011594, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37611054

RESUMO

Treponema pallidum (Tp) has a well-known ability to evade the immune system and can cause neurosyphilis by invading the central nervous system (CNS). Microglia are resident macrophages of the CNS that are essential for host defense against pathogens, this study aims to investigate the interaction between Tp and microglia and the potential mechanism. Here, we found that Tp can exert significant toxic effects on microglia in vivo in Tg (mpeg1: EGFP) transgenic zebrafish embryos. Single-cell RNA sequencing results showed that Tp downregulated autophagy-related genes in human HMC3 microglial cells, which is negatively associated with apoptotic gene expression. Biochemical and cell biology assays further established that Tp inhibits microglial autophagy by interfering with the autophagosome-lysosome fusion process. Transcription factor EB (TFEB) is a master regulator of lysosome biogenesis, Tp activates the mechanistic target of rapamycin complex 1 (mTORC1) signaling to inhibit the nuclear translocation of TFEB, leading to decreased lysosomal biogenesis and accumulated autophagosome. Importantly, the inhibition of autophagosome formation reversed Tp-induced apoptosis and promoted microglial clearance of Tp. Taken together, these findings show that Tp blocks autophagic flux by inhibiting TFEB-mediated lysosomal biosynthesis in human microglia. Autophagosome accumulation was demonstrated to be a key mechanism underlying the effects of Tp in promoting apoptosis and preventing itself from clearing by human microglia. This study offers novel perspectives on the potential mechanism of immune evasion employed by Tp within CNS. The results not only establish the pivotal role of autophagy dysregulation in the detrimental effects of Tp on microglial cells but also bear considerable implications for the development of therapeutic strategies against Tp, specifically involving mTORC1 inhibitors and autophagosome formation inhibitors, in the context of neurosyphilis patients.


Assuntos
Microglia , Neurossífilis , Humanos , Animais , Treponema pallidum/genética , Peixe-Zebra , Autofagia , Apoptose
7.
Mol Cell ; 65(6): 1029-1043.e5, 2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28306502

RESUMO

Class III PI3-kinase (PI3KC3) is essential for autophagy initiation, but whether PI3KC3 participates in other steps of autophagy remains unknown. The HOPS complex mediates the fusion of intracellular vesicles to lysosome, but how HOPS specifically tethers autophagosome to lysosome remains elusive. Here, we report Pacer (protein associated with UVRAG as autophagy enhancer) as a regulator of autophagy. Pacer localizes to autophagic structures and positively regulates autophagosome maturation. Mechanistically, Pacer antagonizes Rubicon to stimulate Vps34 kinase activity. Next, Pacer recruits PI3KC3 and HOPS complexes to the autophagosome for their site-specific activation by anchoring to the autophagosomal SNARE Stx17. Furthermore, Pacer is crucial for the degradation of hepatic lipid droplets, the suppression of Salmonella infection, and the clearance of protein aggregates. These results not only identify Pacer as a crucial multifunctional enhancer in autophagy but also uncover both the involvement of PI3KC3 and the mediators of HOPS's specific tethering activity in autophagosome maturation.


Assuntos
Autofagossomos/enzimologia , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Qa-SNARE/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Relacionadas à Autofagia/genética , Endossomos/enzimologia , Ativação Enzimática , Células HEK293 , Células HeLa , Células Hep G2 , Hepatócitos/enzimologia , Interações Hospedeiro-Patógeno , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Gotículas Lipídicas/metabolismo , Lisossomos/enzimologia , Fusão de Membrana , Agregados Proteicos , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Qa-SNARE/genética , Interferência de RNA , Salmonella typhimurium/crescimento & desenvolvimento , Transdução de Sinais , Fatores de Tempo , Transfecção , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas de Transporte Vesicular/genética
8.
Cell Mol Life Sci ; 81(1): 247, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829550

RESUMO

BACKGROUND: The high degree of intratumoral genomic heterogeneity is a major obstacle for glioblastoma (GBM) tumors, one of the most lethal human malignancies, and is thought to influence conventional therapeutic outcomes negatively. The proneural-to-mesenchymal transition (PMT) of glioma stem cells (GSCs) confers resistance to radiation therapy in glioblastoma patients. POLD4 is associated with cancer progression, while the mechanisms underlying PMT and tumor radiation resistance have remained elusive. METHOD: Expression and prognosis of the POLD family were analyzed in TCGA, the Chinese Glioma Genome Atlas (CGGA) and GEO datasets. Tumorsphere formation and in vitro limiting dilution assay were performed to investigate the effect of UCHL3-POLD4 on GSC self-renewal. Apoptosis, TUNEL, cell cycle phase distribution, modification of the Single Cell Gel Electrophoresis (Comet), γ-H2AX immunofluorescence, and colony formation assays were conducted to evaluate the influence of UCHL3-POLD4 on GSC in ionizing radiation. Coimmunoprecipitation and GST pull-down assays were performed to identify POLD4 protein interactors. In vivo, intracranial xenograft mouse models were used to investigate the molecular effect of UCHL3, POLD4 or TCID on GCS. RESULT: We determined that POLD4 was considerably upregulated in MES-GSCs and was associated with a meagre prognosis. Ubiquitin carboxyl terminal hydrolase L3 (UCHL3), a DUB enzyme in the UCH protease family, is a bona fide deubiquitinase of POLD4 in GSCs. UCHL3 interacted with, depolyubiquitinated, and stabilized POLD4. Both in vitro and in vivo assays indicated that targeted depletion of the UCHL3-POLD4 axis reduced GSC self-renewal and tumorigenic capacity and resistance to IR treatment by impairing homologous recombination (HR) and nonhomologous end joining (NHEJ). Additionally, we proved that the UCHL3 inhibitor TCID induced POLD4 degradation and can significantly enhance the therapeutic effect of IR in a gsc-derived in situ xenograft model. CONCLUSION: These findings reveal a new signaling axis for GSC PMT regulation and highlight UCHL3-POLD4 as a potential therapeutic target in GBM. TCID, targeted for reducing the deubiquitinase activity of UCHL3, exhibited significant synergy against MES GSCs in combination with radiation.


Assuntos
Células-Tronco Neoplásicas , Tolerância a Radiação , Ubiquitina Tiolesterase , Humanos , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Tolerância a Radiação/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Animais , Camundongos , Linhagem Celular Tumoral , Glioma/patologia , Glioma/genética , Glioma/radioterapia , Glioma/metabolismo , Apoptose/genética , Apoptose/efeitos da radiação , Ubiquitinação , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Camundongos Nus , Fenótipo , Regulação Neoplásica da Expressão Gênica , Prognóstico
9.
Plant J ; 116(6): 1842-1855, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665679

RESUMO

Perennial monocarpic mass flowering represents as a key developmental innovation in flowering time diversity in several biological and economical essential families, such as the woody bamboos and the shrubby Strobilanthes. However, molecular and genetic mechanisms underlying this important biodiversity remain poorly investigated. Here, we generated a full-length transcriptome resource incorporated into the BlueOmics database (http://blueomics.iflora.cn) for two Strobilanthes species, which feature contrasting flowering time behaviors. Using about 112 and 104 Gb Iso-seq reads together with ~185 and ~75 Gb strand-specific RNA seq data, we annotated 80 971 and 79 985 non-redundant full-length transcripts for the perennial polycarpic Strobilanthes tetrasperma and the perennial monocarpic Strobilanthes biocullata, respectively. In S. tetrasperma, we identified 8794 transcripts showing spatiotemporal expression in nine tissues. In leaves and shoot apical meristems at two developmental stages, 977 and 1121 transcripts were differentially accumulated in S. tetrasperma and S. biocullata, respectively. Interestingly, among the 33 transcription factors showing differential expression in S. tetrasperma but without differential expression in S. biocullata, three were involved potentially in the photoperiod and circadian-clock pathway of flowering time regulation (FAR1 RELATED SEQUENCE 12, FRS12; NUCLEAR FACTOR Y A1, NFYA1; PSEUDO-RESPONSE REGULATOR 5, PRR5), hence provides an important clue in deciphering the flowering diversity mechanisms. Our data serve as a key resource for further dissection of molecular and genetic mechanisms underpinning key biological innovations, here, the perennial monocarpic mass flowering.


Assuntos
Flores , Transcriptoma , Humanos , Transcriptoma/genética , Flores/genética , Flores/metabolismo , Perfilação da Expressão Gênica , Folhas de Planta/metabolismo , RNA-Seq , Regulação da Expressão Gênica de Plantas/genética
10.
BMC Genomics ; 25(1): 328, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566015

RESUMO

BACKGROUND: Whole-genome duplication and long terminal repeat retrotransposons (LTR-RTs) amplification in organisms are essential factors that affect speciation, local adaptation, and diversification of organisms. Understanding the karyotype projection and LTR-RTs amplification could contribute to untangling evolutionary history. This study compared the karyotype and LTR-RTs evolution in the genomes of eight oaks, a dominant lineage in Northern Hemisphere forests. RESULTS: Karyotype projections showed that chromosomal evolution was relatively conservative in oaks, especially on chromosomes 1 and 7. Modern oak chromosomes formed through multiple fusions, fissions, and rearrangements after an ancestral triplication event. Species-specific chromosomal rearrangements revealed fragments preserved through natural selection and adaptive evolution. A total of 441,449 full-length LTR-RTs were identified from eight oak genomes, and the number of LTR-RTs for oaks from section Cyclobalanopsis was larger than in other sections. Recent amplification of the species-specific LTR-RTs lineages resulted in significant variation in the abundance and composition of LTR-RTs among oaks. The LTR-RTs insertion suppresses gene expression, and the suppressed intensity in gene regions was larger than in promoter regions. Some centromere and rearrangement regions indicated high-density peaks of LTR/Copia and LTR/Gypsy. Different centromeric regional repeat units (32, 78, 79 bp) were detected on different Q. glauca chromosomes. CONCLUSION: Chromosome fusions and arm exchanges contribute to the formation of oak karyotypes. The composition and abundance of LTR-RTs are affected by its recent amplification. LTR-RTs random retrotransposition suppresses gene expression and is enriched in centromere and chromosomal rearrangement regions. This study provides novel insights into the evolutionary history of oak karyotypes and the organization, amplification, and function of LTR-RTs.


Assuntos
Quercus , Retroelementos , Quercus/genética , Genoma de Planta , Cariótipo , Sequências Repetidas Terminais/genética , Evolução Molecular , Filogenia
11.
EMBO J ; 39(5): e102608, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31930741

RESUMO

Degradation of endoplasmic reticulum (ER) by selective autophagy (ER-phagy) is crucial for ER homeostasis. However, it remains unclear how ER scission is regulated for subsequent autophagosomal sequestration and lysosomal degradation. Here, we show that oligomerization of ER-phagy receptor FAM134B (also referred to as reticulophagy regulator 1 or RETREG1) through its reticulon-homology domain is required for membrane fragmentation in vitro and ER-phagy in vivo. Under ER-stress conditions, activated CAMK2B phosphorylates the reticulon-homology domain of FAM134B, which enhances FAM134B oligomerization and activity in membrane fragmentation to accommodate high demand for ER-phagy. Unexpectedly, FAM134B G216R, a variant derived from a type II hereditary sensory and autonomic neuropathy (HSAN) patient, exhibits gain-of-function defects, such as hyperactive self-association and membrane scission, which results in excessive ER-phagy and sensory neuron death. Therefore, this study reveals a mechanism of ER membrane fragmentation in ER-phagy, along with a signaling pathway in regulating ER turnover, and suggests a potential implication of excessive selective autophagy in human diseases.


Assuntos
Autofagia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Estresse do Retículo Endoplasmático , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Membrana Celular/metabolismo , Citocinese/fisiologia , Retículo Endoplasmático/metabolismo , Mutação com Ganho de Função , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lisossomos/metabolismo , Proteínas de Membrana/genética , Polimerização
12.
BMC Plant Biol ; 24(1): 168, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438905

RESUMO

BACKGROUND: Forests are essential for maintaining species diversity, stabilizing local and global climate, and providing ecosystem services. Exploring the impact of paleogeographic events and climate change on the genetic structure and distribution dynamics of forest keystone species could help predict responses to future climate change. In this study, we combined an ensemble species distribution model (eSDM) and multilocus phylogeography to investigate the spatial genetic patterns and distribution change of Quercus glauca Thunb, a keystone of East Asian subtropical evergreen broad-leaved forest. RESULTS: A total of 781 samples were collected from 77 populations, largely covering the natural distribution of Q. glauca. The eSDM showed that the suitable habitat experienced a significant expansion after the last glacial maximum (LGM) but will recede in the future under a general climate warming scenario. The distribution centroid will migrate toward the northeast as the climate warms. Using nuclear SSR data, two distinct lineages split between east and west were detected. Within-group genetic differentiation was higher in the West than in the East. Based on the identified 58 haplotypes, no clear phylogeographic structure was found. Populations in the Nanling Mountains, Wuyi Mountains, and the southwest region were found to have high genetic diversity. CONCLUSIONS: A significant negative correlation between habitat stability and heterozygosity might be explained by the mixing of different lineages in the expansion region after LGM and/or hybridization between Q. glauca and closely related species. The Nanling Mountains may be important for organisms as a dispersal corridor in the west-east direction and as a refugium during the glacial period. This study provided new insights into spatial genetic patterns and distribution dynamics of Q. glauca.


Assuntos
Ecossistema , Quercus , Quercus/genética , Filogeografia , Florestas , Mudança Climática
13.
Small ; 20(3): e2305711, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37697703

RESUMO

The typical chalcopyrite AgGaQ2 (Q = S, Se) are commercial infrared (IR) second-order nonlinear optical (NLO) materials; however, they suffer from unexpected laser-induced damage thresholds (LIDTs) primairy due to their narrow band gaps. Herein, what sets this apart from previously reported chemical substitutions is the utilization of an unusual cationic substitution strategy, represented by [[SZn4 ]S12 + [S4 Zn13 ]S24 + 11ZnS4 ⇒ MS12 + [M4 Cl]S24 + 11GaS4 ], in which the covalent Sx Zny units in the diamond-like sphalerite ZnS are synergistically replaced by cationic Mx Cly units, resulting in two novel salt-inclusion sulfides, M[M4 Cl][Ga11 S20 ] (M = A/Ba, A = K, 1; Rb, 2). As expected, the introduction of mixed cations in the GaS4 anionic frameworks of 1 and 2 leads to wide band gaps (3.04 and 3.01 eV), which exceeds the value of AgGaS2 , facilitating the improvement of high LIDTs (9.4 and 10.3 × AgGaS2 @1.06 µm, respectively). Furthermore, compounds 1 and 2 exhibit moderate second-harmonic generation intensities (0.84 and 0.78 × AgGaS2 @2.9 µm, respectively), mainly originating from the orderly packing tetrahedral GaS4 units. Importantly, this study demonstrates the successful application of the cationic substitution strategy based on diamond-like structures to provide a feasible chemical design insight for constructing high-performance NLO materials.

14.
Plant Physiol ; 192(1): 154-169, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36721922

RESUMO

Flowering transition is tightly coordinated by complex gene regulatory networks, in which AGAMOUS-LIKE 16 (AGL16) plays important roles. Here, we identified the molecular function and binding properties of AGL16 and demonstrated its partial dependency on the SUPPRESSOR OF CONSTANS 1 (SOC1) function in regulating flowering. AGL16 bound to promoters of more than 2,000 genes via CArG-box motifs with high similarity to that of SOC1 in Arabidopsis (Arabidopsis thaliana). Approximately 70 flowering genes involved in multiple pathways were potential targets of AGL16. AGL16 formed a protein complex with SOC1 and shared a common set of targets. Intriguingly, only a limited number of genes were differentially expressed in the agl16-1 loss-of-function mutant. However, in the soc1-2 knockout background, AGL16 repressed and activated the expression of 375 and 182 genes, respectively, with more than a quarter bound by AGL16. Corroborating these findings, AGL16 repressed the flowering time more strongly in soc1-2 than in the Col-0 background. These data identify a partial inter-dependency between AGL16 and SOC1 in regulating genome-wide gene expression and flowering time, while AGL16 provides a feedback regulation on SOC1 expression. Our study sheds light on the complex background dependency of AGL16 in flowering regulation, thus providing additional insights into the molecular coordination of development and environmental adaptation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Regiões Promotoras Genéticas/genética , Regulação da Expressão Gênica de Plantas , Flores
15.
J Exp Bot ; 75(11): 3233-3247, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38546444

RESUMO

Floral forms with an increased number of petals, also known as double-flower phenotypes, have been selected and conserved in many domesticated plants, particularly in ornamentals, because of their great economic value. The molecular and genetic mechanisms that control this trait are therefore of great interest, not only for scientists, but also for breeders. In this review, we summarize current knowledge of the gene regulatory networks of flower initiation and development and known mutations that lead to variation of petal number in many species. In addition to the well-accepted miR172/AP2-like module, for which many questions remain unanswered, we also discuss other pathways in which mutations also lead to the formation of extra petals, such as those involved in meristem maintenance, hormone signalling, epigenetic regulation, and responses to environmental signals. We discuss how the concept of 'natural mutants' and recent advances in genomics and genome editing make it possible to explore the molecular mechanisms underlying double-flower formation, and how such knowledge could contribute to the future breeding and selection of this trait in more crops.


Assuntos
Flores , Flores/genética , Flores/crescimento & desenvolvimento , Flores/anatomia & histologia , Regulação da Expressão Gênica de Plantas , Mutação , Redes Reguladoras de Genes
16.
J Exp Bot ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642399

RESUMO

Plant life-history is determined by two transitions, the germination and the flowering times, in which the phosphatidylethanolamine-binding proteins (PEBP) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1) play key regulatory roles. Compared to the highly conserved TFL1-likes, FT-like genes vary in copy numbers significantly in gymnosperms and monocots of the angiosperms, while sporadic duplications can be observed in eudicots. Here, via a systematic analysis of the PEBPs in angiosperms with a special focus on twelve representative species featuring high-quality genomes in the Lamiales order, we identified a successive lineage-specific but systematic expansion of FT-like genes in the families of core Lamiales. The first expansion event generated FT1-likes mainly via a core-Lamiales-specific whole-genome-duplication (cL-WGD), while on the other hand, a likely random duplication produced the FT2-likes in the lineages containing Scrophulariaceae and rest of the core Lamiales. Both FT1- and FT2-like genes were further amplified tandemly in some families. These expanded FT-likes featured highly diverged expression patterns and structural variation, indicating functional diversification. Intriguingly, some core Lamiales contained the relict MOTHER OF FT AND TFL1 like 2 (MFT2) that likely expanded in the common ancestor of angiosperms. Our data showcase the highly dynamic lineage-specific expansion of the FT-like genes, thus provide important and fresh evolutionary insights into the gene-regulatory-network underpinning flowering time diversity in Lamiales, and more generally, in angiosperms.

17.
J Magn Reson Imaging ; 59(5): 1787-1797, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37671487

RESUMO

BACKGROUND: A referenced MRI-based classification associated with focused ultrasound ablation surgery (FUAS) outcomes is lacking in adenomyosis. PURPOSE: To identify an MRI-based classification system for informing the FUAS outcomes. STUDY TYPE: Retrospective. POPULATION: Patients with FUAS for adenomyosis, were divided into a training set (N = 643; 355 with post-FUAS gonadotropin-releasing hormone/levonorgestrel, 288 without post-FUAS therapy) and an external validation set (N = 135; all without post-FUAS therapy). FIELD STRENGTH/SEQUENCE: 1.5 T, turbo spin-echo T2-weighted imaging and single-shot echo-planar diffusion-weighted imaging sequences. ASSESSMENT: Five MRI-based adenomyosis classifications: classification 1 (C1) (diffuse, focal, and mild), C2 (intrinsic, extrinsic, intramural, and indeterminate), C3 (internal, adenomyomas, and external), C4 (six subtypes on areas [internal or external] and volumes [<1/3 or ≥2/3]), and C5 (internal [asymmetric or symmetric], external, intramural, full thickness [asymmetric or symmetric]) for FUAS outcomes (symptom relief and recurrence). STATISTICAL TESTS: The optimal classification was significantly associated with the most subtypes of FUAS outcomes. Relating to the timing of recurrence was measured using Cox regression analysis and median recurrence time was estimated by a Kaplan-Meier curve. A P value <0.05 was considered statistically significant. RESULTS: Dysmenorrhea relief and recurrence were only associated with C2 in training patients undergoing FUAS alone. Compared with other subtypes, the extrinsic subtype of C2 was significantly associated with dysmenorrhea recurrence in the FUAS group. Besides, the median dysmenorrhea recurrence time of extrinsic subtype was significantly shorter than that of other subtypes (42.0 months vs. 50.3 months). In the validation cohort, C2 was confirmed as the optimal system and its extrinsic subtype was confirmed to have a significantly shorter dysmenorrhea recurrence time than other subtypes. DATA CONCLUSION: Classification 2 can inform dysmenorrhea relief and recurrence in patients with adenomyosis undergoing FAUS only. Itsextrinsic subtype was associated with an earlier onset of dysmenorrhea recurrence after treatment. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 5.


Assuntos
Adenomiose , Ablação por Ultrassom Focalizado de Alta Intensidade , Feminino , Humanos , Adenomiose/diagnóstico por imagem , Adenomiose/cirurgia , Dismenorreia/diagnóstico por imagem , Dismenorreia/complicações , Dismenorreia/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Ultrassonografia de Intervenção/métodos
18.
FASEB J ; 37(7): e22960, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37335566

RESUMO

Anovulation is the main feature of infertile women with polycystic ovary syndrome (PCOS), and there is very limited understanding of the role of plasma exosomes and miRNAs in it. To identify the effect of PCOS patients' plasma exosomes and exosomal miRNAs, we isolated plasma exosomes of PCOS patients and normal women and injected into 8-week-old ICR female mice via tail vein. The changes in estrus cycle, serum hormone levels, and ovarian morphology were observed. KGN cells were cultured and transfected with mimics and inhibitors of differentially expressed exosomal miRNAs (miR-18a-3p, miR-20b-5p, miR-106a-5p, miR-126-3p, and miR-146a-5p) and then tested for steroid hormone synthesis, proliferation, and apoptosis. The results showed that female ICR mice injected with plasma exosomes from PCOS patients presented ovarian oligo-cyclicity. Hormone synthesis and proliferation of granulosa cells were affected by differentially expressed PCOS plasma-derived exosomal miRNAs, of which miR-126-3p having the most evident effect. MiR-126-3p affected the proliferation of granulosa cells by inhibiting PDGFRß and its downstream PI3K-AKT pathway. Our results demonstrated plasma exosomes and contained miRNAs in PCOS patients affect the estrus cycle of mice, hormone secretion, and proliferation of granulosa cells. This study provides a novel understanding about the function of plasma exosomes and exosomal miRNAs in PCOS.


Assuntos
Exossomos , Infertilidade Feminina , MicroRNAs , Síndrome do Ovário Policístico , Animais , Feminino , Humanos , Camundongos , Exossomos/genética , Exossomos/metabolismo , Células da Granulosa/metabolismo , Hormônios/metabolismo , Infertilidade Feminina/metabolismo , Camundongos Endogâmicos ICR , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo
19.
Reprod Biomed Online ; 49(2): 103977, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38824761

RESUMO

RESEARCH QUESTION: Can microbes vertically transmit from semen and follicular fluid to embryo culture media during assisted reproductive technology (ART) treatment? DESIGN: Spent embryo culture media (SECM), seminal fluid and follicular fluid samples were collected from 61 couples with infertility undergoing ART treatment at the Prince of Wales Hospital, Hong Kong SAR, China. Metagenomic analysis was conducted using 16s rRNA sequencing to identify the source of microbes in SECM, correlation between the semen microbiome and male infertility, and correlation between the follicular fluid microbiome and female infertility. RESULTS: Microbial vertical transmission into SECM was reported in 82.5% of cases, and semen was the main source of contamination in conventional IVF cases. The increased abundances of Staphylococcus spp. and Streptococcus anginosus in semen had negative impacts on total motility and sperm count, respectively (P < 0.001). Significant increases in abundance of the genera Prophyromonas, Neisseria and Facklamia were observed in follicular fluid in women with anovulation, uterine factor infertility and unexplained infertility, respectively (P < 0.01). No significant correlation was found between the bacteria identified in all sample types and ART outcomes, including fertilization rate, embryo development, number of available embryos, and clinical pregnancy rate. CONCLUSION: Embryo culture media can be contaminated during ART treatment, not only by seminal microbes but also by follicular fluid and other sources of microbes. Strong correlations were found between specific microbial taxa in semen and sperm quality, and between the follicular fluid microbiome and the aetiology of female infertility. However, no significant association was found between the microbiomes of SECM, semen and follicular fluid and ART outcomes.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38695864

RESUMO

A novel actinobacterium, designated strain CWNU-1T, was isolated from the rhizospheric soil of Fritillaria cirrhosa D. Don and examined using a polyphasic taxonomic approach. The organism developed pale blue aerial mycelia that was simply branched and terminated in open or closed coils of three or more volutions on International Streptomyces Project 3 agar. Spores were ellipsoidal to cylindrical with wrinkled surfaces. The strain showed high 16S rRNA gene sequence similarity to Streptomyces kurssanovii NBRC 13192T (98.8 %), Streptomyces xantholiticus NBRC 13354T (98.7 %) and Streptomyces peucetius JCM 9920T (98.6 %). The phylogenetic result based on 16S rRNA gene and genome sequences clearly demonstrated that strain CWNU-1T formed an independent phylogenetic lineage. On the basis of orthologous average nucleotide identity, CWNU-1T was most closely related to Streptomyces inusitatus NBRC 13601T with 79.3 % identity. The results of the digital DNA-DNA hybridization analysis also indicated low levels of relatedness with other species, as the highest value was observed with S. inusitatus NBRC 13601T (25.3 %). With reference to phenotypic characteristics, phylogenetic data, orthologous average nucleotide identity and digital DNA-DNA hybridization results, strain CWNU-1T was readily distinguished from its most closely related strains and classified as representing a novel species, for which the name Streptomyces albipurpureus sp. nov. is proposed. The type strain is CWNU-1T (=CGMCC 4.7758T=MCCC 1K07402T=JCM 35391T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Fritillaria , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Rizosfera , Análise de Sequência de DNA , Microbiologia do Solo , Streptomyces , Streptomyces/genética , Streptomyces/classificação , Streptomyces/isolamento & purificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Fritillaria/microbiologia , Vitamina K 2/análogos & derivados
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