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1.
Nature ; 623(7986): 334-339, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37758955

RESUMO

Formation of continental crust has shaped the surface and interior of our planet and generated the land and mineral resources on which we rely. However, how the early continental crust of Earth formed is still debated1-7. Modern continental crust is largely formed from wet and oxidizing arc magmas at subduction zones, in which oceanic lithosphere and water recycle into the mantle8-10. The magmatic H2O content and redox state of ancient rocks that constitute the early continental crust, however, are difficult to quantify owing to ubiquitous metamorphism. Here we combine two zircon oxybarometers11,12 to simultaneously determine magmatic oxygen fugacity (fO2) and H2O content of Archaean (4.0-2.5 billion years ago) granitoids that dominate the early continental crust. We show that most Archaean granitoid magmas were ≥1 log unit more oxidizing than Archaean ambient mantle-derived magmas13,14 and had high magmatic H2O contents (6-10 wt%) and high H2O/Ce ratios (>1,000), similar to modern arc magmas. We find that magmatic fO2, H2O contents and H2O/Ce ratios of Archaean granitoids positively correlate with depth of magma formation, requiring transport of large amounts of H2O to the lower crust and mantle. These observations can be readily explained by subduction but are difficult to reconcile with non-subduction models of crustal formation3-7. We note an increase in magmatic fO2 and H2O content between 4.0 and 3.6 billion years ago, probably indicating the onset of subduction during this period.

2.
Proc Natl Acad Sci U S A ; 121(26): e2318761121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38885389

RESUMO

Archaea produce unique membrane-spanning lipids (MSLs), termed glycerol dialkyl glycerol tetraethers (GDGTs), which aid in adaptive responses to various environmental challenges. GDGTs can be modified through cyclization, cross-linking, methylation, hydroxylation, and desaturation, resulting in structurally distinct GDGT lipids. Here, we report the identification of radical SAM proteins responsible for two of these modifications-a glycerol monoalkyl glycerol tetraether (GMGT) synthase (Gms), responsible for covalently cross-linking the two hydrocarbon tails of a GDGT to produce GMGTs, and a GMGT methylase (Gmm), capable of methylating the core hydrocarbon tail. Heterologous expression of Gms proteins from various archaea in Thermococcus kodakarensis results in the production of GMGTs in two isomeric forms. Further, coexpression of Gms and Gmm produces mono- and dimethylated GMGTs and minor amounts of trimethylated GMGTs with only trace GDGT methylation. Phylogenetic analyses reveal the presence of Gms homologs in diverse archaeal genomes spanning all four archaeal superphyla and in multiple bacterial phyla with the genetic potential to synthesize fatty acid-based MSLs, demonstrating that GMGT production may be more widespread than previously appreciated. We demonstrate GMGT production in three Gms-encoding archaea, identifying an increase in GMGTs in response to elevated temperature in two Archaeoglobus species and the production of GMGTs with up to six rings in Vulcanisaeta distributa. The occurrence of such highly cyclized GMGTs has been limited to environmental samples and their detection in culture demonstrates the utility of combining genetic, bioinformatic, and lipid analyses to identify producers of distinct archaeal membrane lipids.


Assuntos
Archaea , Proteínas Arqueais , Filogenia , Proteínas Arqueais/metabolismo , Proteínas Arqueais/genética , Archaea/metabolismo , Archaea/genética , Thermococcus/metabolismo , Thermococcus/genética , Éteres de Glicerila/metabolismo , Lipídeos de Membrana/metabolismo , Lipídeos de Membrana/biossíntese
3.
Proc Natl Acad Sci U S A ; 121(35): e2317182121, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39172793

RESUMO

From microbes to humans, organisms perform numerous tasks for their survival, including food acquisition, migration, and reproduction. A complex biological task can be performed by either an autonomous organism or by cooperation among several specialized organisms. However, it remains unclear how autonomy and cooperation evolutionarily switch. Specifically, it remains unclear whether and how cooperative specialists can repair deleted genes through direct genetic exchange, thereby regaining metabolic autonomy. Here, we address this question by experimentally evolving a mutualistic microbial consortium composed of two specialists that cooperatively degrade naphthalene. We observed that autonomous genotypes capable of performing the entire naphthalene degradation pathway evolved from two cooperative specialists and dominated the community. This evolutionary transition was driven by the horizontal gene transfer (HGT) between the two specialists. However, this evolution was exclusively observed in the fluctuating environment alternately supplied with naphthalene and pyruvate, where mutualism and competition between the two specialists alternated. The naphthalene-supplied environment exerted selective pressure that favors the expansion of autonomous genotypes. The pyruvate-supplied environment promoted the coexistence and cell density of the cooperative specialists, thereby increasing the likelihood of HGT. Using a mathematical model, we quantitatively demonstrate that environmental fluctuations facilitate the evolution of autonomy through HGT when the relative growth rate and carrying capacity of the cooperative specialists allow enhanced coexistence and higher cell density in the competitive environment. Together, our results demonstrate that cooperative specialists can repair deleted genes through a direct genetic exchange under specific conditions, thereby regaining metabolic autonomy.


Assuntos
Naftalenos , Naftalenos/metabolismo , Transferência Genética Horizontal , Evolução Biológica , Simbiose , Consórcios Microbianos/genética , Consórcios Microbianos/fisiologia , Genótipo
4.
J Immunol ; 212(3): 397-409, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38088801

RESUMO

SHP-1 (Src homology region 2 domain-containing phosphatase 1) is a well-known negative regulator of T cells, whereas its close homolog SHP-2 is the long-recognized main signaling mediator of the PD-1 inhibitory pathway. However, recent studies have challenged the requirement of SHP-2 in PD-1 signaling, and follow-up studies further questioned the alternative idea that SHP-1 may replace SHP-2 in its absence. In this study, we systematically investigate the role of SHP-1 alone or jointly with SHP-2 in CD8+ T cells in a series of gene knockout mice. We show that although SHP-1 negatively regulates CD8+ T cell effector function during acute lymphocytic choriomeningitis virus (LCMV) infection, it is dispensable for CD8+ T cell exhaustion during chronic LCMV infection. Moreover, in contrast to the mortality of PD-1 knockout mice upon chronic LCMV infection, mice double deficient for SHP-1 and SHP-2 in CD8+ T cells survived without immunopathology. Importantly, CD8+ T cells lacking both phosphatases still differentiate into exhausted cells and respond to PD-1 blockade. Finally, we found that SHP-1 and SHP-2 suppressed effector CD8+ T cell expansion at the early and late stages, respectively, during chronic LCMV infection.


Assuntos
Coriomeningite Linfocítica , Vírus da Coriomeningite Linfocítica , Animais , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Morte Celular Programada 1/metabolismo , Exaustão das Células T
5.
Mol Ther ; 32(3): 637-645, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38204163

RESUMO

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.


Assuntos
Doenças Cardiovasculares , Hepatócitos , Humanos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/química , Análise Custo-Benefício , RNA de Cadeia Dupla , Acetilgalactosamina/química , Proteína 3 Semelhante a Angiopoietina
6.
Cell Mol Life Sci ; 81(1): 88, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349408

RESUMO

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia, and recent epidemiological studies suggested type 2 diabetes mellitus (T2DM) is an independent risk factor for the development of AF. Zinc finger and BTB (broad-complex, tram-track and bric-a-brac) domain containing 16 (Zbtb16) serve as transcriptional factors to regulate many biological processes. However, the potential effects of Zbtb16 in AF under T2DM condition remain unclear. Here, we reported that db/db mice displayed higher AF vulnerability and Zbtb16 was identified as the most significantly enriched gene by RNA sequencing (RNA-seq) analysis in atrium. In addition, thioredoxin interacting protein (Txnip) was distinguished as the key downstream gene of Zbtb16 by Cleavage Under Targets and Tagmentation (CUT&Tag) assay. Mechanistically, increased Txnip combined with thioredoxin 2 (Trx2) in mitochondrion induced excess reactive oxygen species (ROS) release, calcium/calmodulin-dependent protein kinase II (CaMKII) overactivation, and spontaneous Ca2+ waves (SCWs) occurrence, which could be inhibited through atrial-specific knockdown (KD) of Zbtb16 or Txnip by adeno-associated virus 9 (AAV9) or Mito-TEMPO treatment. High glucose (HG)-treated HL-1 cells were used to mimic the setting of diabetic in vitro. Zbtb16-Txnip-Trx2 signaling-induced excess ROS release and CaMKII activation were also verified in HL-1 cells under HG condition. Furthermore, atrial-specific Zbtb16 or Txnip-KD reduced incidence and duration of AF in db/db mice. Altogether, we demonstrated that interrupting Zbtb16-Txnip-Trx2 signaling in atrium could decrease AF susceptibility via reducing ROS release and CaMKII activation in the setting of T2DM.


Assuntos
Fibrilação Atrial , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animais , Camundongos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas de Transporte/genética , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica , Espécies Reativas de Oxigênio , Tiorredoxinas/genética
7.
Proc Natl Acad Sci U S A ; 119(49): e2215990119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454763

RESUMO

Recent characterization of the obligate episymbiont Saccharibacteria (TM7) belonging to the candidate phyla radiation (CPR) has expanded the extent of microbial diversity. However, the episymbiotic lifestyle of TM7 is still underexploited due to the deficiency of cultivated representatives. Here, we describe gene-targeted TM7 cultivation guided by repurposing epicPCR (emulsion, paired isolation, and concatenation PCR) to capture in situ TM7‒host associations. Using this method, we obtained a novel Saccharibacteria isolate TM7i and its host Leucobacter aridicollis J1 from Cicadae Periostracum, the castoff shell of cicada. Genomic analyses and microscopic characterizations revealed that TM7i could bind to J1 through twitching-like motility mediated by type IV pili (T4P). We further showed that the inhibition of T4P extrusion suppressed the motility and host adherence of TM7i, resulting in its reduced growth. However, the inactivation of T4P had little effect on the growth of TM7i that had already adhered to J1, suggesting the essential role of T4P in host recognition by TM7i. By capturing CPR‒host association and elaborating the T4P-dependent episymbiotic association mechanism, our studies shed light on the distinct yet widespread lifestyle of CPR bacteria.


Assuntos
Actinomycetales , Fímbrias Bacterianas , Fímbrias Bacterianas/genética , Bactérias , Reação em Cadeia da Polimerase , Genômica
8.
Proc Natl Acad Sci U S A ; 119(17): e2117065119, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35467979

RESUMO

High-grade serous ovarian cancer (HGSOC) is a lethal malignancy characterized by an immunosuppressive tumor microenvironment containing few tumor infiltrating lymphocytes (TILs) and an insensitivity to checkpoint inhibitor immunotherapies. Gains in the PTK2 gene encoding focal adhesion kinase (FAK) at Chr8 q24.3 occur in ∼70% of HGSOC tumors, and elevated FAK messenger RNA (mRNA) levels are associated with poor patient survival. Herein, we show that active FAK, phosphorylated at tyrosine-576 within catalytic domain, is significantly increased in late-stage HGSOC tumors. Active FAK costained with CD155, a checkpoint receptor ligand for TIGIT (T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains), in HGSOC tumors and a selective association between FAK and TIGIT checkpoint ligands were supported by patient transcriptomic database analysis. HGSOC tumors with high FAK expression were associated with low CD3 mRNA levels. Accordingly, late-stage tumors showed elevated active FAK staining and significantly lower levels of CD3+ TILs. Using the KMF (Kras, Myc, FAK) syngeneic ovarian tumor model containing spontaneous PTK2 (FAK) gene gains, the effects of tumor intrinsic genetic or oral small molecule FAK inhibitior (FAKi; VS-4718) were evaluated in vivo. Blocking FAK activity decreased tumor burden, suppressed ascites KMF-associated CD155 levels, and increased peritoneal TILs. The combination of FAKi with blocking TIGIT antibody (1B4) maintained elevated TIL levels and reduced TIGIT+ T regulatory cell levels, prolonged host survival, increased CXCL13 levels, and led to the formation of omental tertiary lymphoid structures. Collectively, our studies support FAK and TIGIT targeting as a rationale immunotherapy combination for HGSOC.


Assuntos
Neoplasias Ovarianas , Animais , Carcinoma Epitelial do Ovário , Feminino , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Terapia de Imunossupressão , Ligantes , Camundongos , Neoplasias Ovarianas/patologia , Receptores Imunológicos/metabolismo
9.
Chem Soc Rev ; 53(18): 9254-9305, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39143899

RESUMO

With the increasing demand for energy and the climate challenges caused by the consumption of traditional fuels, there is an urgent need to accelerate the adoption of green and sustainable energy conversion and storage technologies. The integration of flexible thermoelectrics with other various energy conversion technologies plays a crucial role, enabling the conversion of multiple forms of energy such as temperature differentials, solar energy, mechanical force, and humidity into electricity. The development of these technologies lays the foundation for sustainable power solutions and promotes research progress in energy conversion. Given the complexity and rapid development of this field, this review provides a detailed overview of the progress of multifunctional integrated energy conversion and storage technologies based on thermoelectric conversion. The focus is on improving material performance, optimizing the design of integrated device structures, and achieving device flexibility to expand their application scenarios, particularly the integration and multi-functionalization of wearable energy conversion technologies. Additionally, we discuss the current development bottlenecks and future directions to facilitate the continuous advancement of this field.

10.
J Cell Mol Med ; 28(17): e70069, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39245801

RESUMO

Phosphoinositide 3-kinase γ (PI3Kγ) is G-protein-coupled receptor-activated lipid kinase with both kinase-dependent and kinase-independent activity. Plenty of evidence have demonstrated that PI3Kγ participated in TAC and I/R-induced myocardial remodelling and heart failure (HF). In this study, we tested the hypothesis that common variants in the PI3Kγ gene (PIK3CG) were associated with the prognosis of HF in the Chinese Han population. Through re-sequencing and genotyping, we finally identified a common variant in the 3'UTR of PIK3CG strongly associated with the prognosis of HF in two-stage population: adjusted p = 0.007, hazard ratio = 0.56 (0.36-0.85) in the first cohort and adjusted p = 0.024, hazard ratio = 0.39 (0.17-0.88) in the replicated cohort. A series of functional assays revealed that rs10215499-A allele suppressed PIK3CG translation by facilitating has-miR-133a-3p binding, but not the G allele. Subjects carrying the GG genotype showed higher mRNA and protein level than those with AA and AG genotype. Furthermore, overexpression of PIK3CG could protect AC16 from hypoxia/reoxygenation (H/R)-induced apoptosis, while the case was opposite for PIK3CG silencing. In conclusion, common variant rs10215499 in the 3'-UTR of PIK3CG might affect the prognosis of HF by interfering with miR-133a-3p binding and PIK3CG is a promising target for HF treatment in the future.


Assuntos
Classe Ib de Fosfatidilinositol 3-Quinase , Insuficiência Cardíaca , Polimorfismo de Nucleotídeo Único , Humanos , Insuficiência Cardíaca/genética , Prognóstico , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Masculino , Feminino , Pessoa de Meia-Idade , MicroRNAs/genética , Idoso , Regiões 3' não Traduzidas/genética , Predisposição Genética para Doença , Alelos , Genótipo , Apoptose/genética
11.
J Biol Chem ; 299(1): 102765, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36470423

RESUMO

Hyperlipidemia characterized by high blood levels of free fatty acids (FFAs) is important for the progression of inflammatory cardiovascular diseases. Integrin ß1 is a transmembrane receptor that drives various cellular functions, including differentiation, migration, and phagocytosis. However, the underlying mechanisms modifying integrin ß1 protein and activity in mediating monocyte/macrophage adhesion to endothelium remain poorly understood. In this study, we demonstrated that integrin ß1 protein underwent S-nitrosylation in response to nitrosative stress in macrophages. To examine the effect of elevated levels of FFA on the modulation of integrin ß1 expression, we treated the macrophages with a combination of oleic acid and palmitic acid (2:1) and found that FFA activated inducible nitric oxide synthase/nitric oxide and increased the integrin ß1 protein level without altering the mRNA level. FFA promoted integrin ß1 S-nitrosylation via inducible nitric oxide synthase/nitric oxide and prevented its degradation by decreasing binding to E3 ubiquitin ligase c-Cbl. Furthermore, we found that increased integrin α4ß1 heterodimerization resulted in monocyte/macrophage adhesion to endothelium. In conclusion, these results provided novel evidence that FFA-stimulated N--O stabilizes integrin ß1via S-nitrosylation, favoring integrin α4ß1 ligation to promote vascular inflammation.


Assuntos
Células Endoteliais , Ácidos Graxos não Esterificados , Monócitos , Ácidos Graxos não Esterificados/metabolismo , Integrina alfa4beta1/metabolismo , Monócitos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Integrina beta1/metabolismo , Estabilidade Proteica , Células Endoteliais/metabolismo , Ligação Proteica , Estresse Fisiológico
12.
J Cell Physiol ; 239(6): e31267, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558303

RESUMO

Cervical cancer (CxCa) is the fourth most frequent cancer in women. This study aimed to determine the role and underlying mechanism of fibronectin type III domain-containing protein 5 (FNDC5) in inhibiting CxCa growth. Experiments were performed in human CxCa tissues, human CxCa cell lines (HeLa and SiHa), and xenograft mouse model established by subcutaneous injection of SiHa cells in nude mice. Bioinformatics analysis showed that CxCa patients with high FNDC5 levels have a longer overall survival period. FNDC5 expression was increased in human CxCa tissues, HeLa and SiHa cells. FNDC5 overexpression or FNDC5 protein not only inhibited proliferation, but also restrained invasion and migration of HeLa and SiHa cells. The effects of FNDC5 were prevented by inhibiting integrin with cilengitide, activating PI3K with recilisib or activating Akt with SC79. FNDC5 inhibited the phosphorylation of PI3K and Akt, which was attenuated by recilisib. PI3K inhibitor LY294002 showed similar effects to FNDC5 in HeLa and SiHa cells. Intravenous injection of FNDC5 (20 µg/day) for 14 days inhibited the tumor growth, and reduced the proliferation marker Ki67 expression and the Akt phosphorylation in the CxCa xenograft mouse model. These results indicate that FNDC5 inhibits the malignant phenotype of CxCa cells through restraining PI3K/Akt signaling. Upregulation of FNDC5 may play a beneficial role in retarding the tumor growth of CxCa.


Assuntos
Proliferação de Células , Fibronectinas , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibronectinas/metabolismo , Fibronectinas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Integrinas/metabolismo , Progressão da Doença
13.
J Am Chem Soc ; 146(2): 1681-1689, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38178655

RESUMO

The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.

14.
BMC Plant Biol ; 24(1): 167, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438916

RESUMO

BACKGROUND: Generating elite rice varieties with high yield and superior quality is the main goal of rice breeding programs. Key agronomic traits, including grain size and seed germination characteristics, affect the final yield and quality of rice. The RGA1 gene, which encodes the α-subunit of rice G-protein, plays an important role in regulating rice architecture, seed size and abiotic stress responses. However, whether RGA1 is involved in the regulation of rice quality and seed germination traits is still unclear. RESULTS: In this study, a rice mutant small and round grain 5 (srg5), was identified in an EMS-induced rice mutant library. Systematic analysis of its major agronomic traits revealed that the srg5 mutant exhibited a semi-dwarf plant height with small and round grain and reduced panicle length. Analysis of the physicochemical properties of rice showed that the difference in rice eating and cooking quality (ECQ) between the srg5 mutant and its wild-type control was small, but the appearance quality was significantly improved. Interestingly, a significant suppression of rice seed germination and shoot growth was observed in the srg5 mutant, which was mainly related to the regulation of ABA metabolism. RGA1 was identified as the candidate gene for the srg5 mutant by BSA analysis. A SNP at the splice site of the first intron disrupted the normal splicing of the RGA1 transcript precursor, resulting in a premature stop codon. Additional linkage analysis confirmed that the target gene causing the srg5 mutant phenotype was RGA1. Finally, the introduction of the RGA1 mutant allele into two indica rice varieties also resulted in small and round rice grains with less chalkiness. CONCLUSIONS: These results indicate that RGA1 is not only involved in the control of rice architecture and grain size, but also in the regulation of rice quality and seed germination. This study sheds new light on the biological functions of RGA1, thereby providing valuable information for future systematic analysis of the G-protein pathway and its potential application in rice breeding programs.


Assuntos
Oryza , Oryza/genética , Sementes/genética , Germinação/genética , Melhoramento Vegetal , Grão Comestível/genética , Proteínas de Ligação ao GTP
15.
Appl Environ Microbiol ; 90(2): e0202523, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38259074

RESUMO

Marine bacteria play important roles in the degradation and cycling of algal polysaccharides. However, the dynamics of epiphytic bacterial communities and their roles in algal polysaccharide degradation during kelp decay are still unclear. Here, we performed metagenomic analyses to investigate the identities and predicted metabolic abilities of epiphytic bacterial communities during the early and late decay stages of the kelp Saccharina japonica. During kelp decay, the dominant epiphytic bacterial communities shifted from Gammaproteobacteria to Verrucomicrobia and Bacteroidetes. In the early decay stage of S. japonica, epiphytic bacteria primarily targeted kelp-derived labile alginate for degradation, among which the gammaproteobacterial Vibrionaceae (particularly Vibrio) and Psychromonadaceae (particularly Psychromonas), abundant in alginate lyases belonging to the polysaccharide lyase (PL) families PL6, PL7, and PL17, were key alginate degraders. More complex fucoidan was preferred to be degraded in the late decay stage of S. japonica by epiphytic bacteria, predominantly from Verrucomicrobia (particularly Lentimonas), Pirellulaceae of Planctomycetes (particularly Rhodopirellula), Pontiellaceae of Kiritimatiellota, and Flavobacteriaceae of Bacteroidetes, which depended on using glycoside hydrolases (GHs) from the GH29, GH95, and GH141 families and sulfatases from the S1_15, S1_16, S1_17, and S1_25 families to depolymerize fucoidan. The pathways for algal polysaccharide degradation in dominant epiphytic bacterial groups were reconstructed based on analyses of metagenome-assembled genomes. This study sheds light on the roles of different epiphytic bacteria in the degradation of brown algal polysaccharides.IMPORTANCEKelps are important primary producers in coastal marine ecosystems. Polysaccharides, as major components of brown algal biomass, constitute a large fraction of organic carbon in the ocean. However, knowledge of the identities and pathways of epiphytic bacteria involved in the degradation process of brown algal polysaccharides during kelp decay is still elusive. Here, based on metagenomic analyses, the succession of epiphytic bacterial communities and their metabolic potential were investigated during the early and late decay stages of Saccharina japonica. Our study revealed a transition in algal polysaccharide-degrading bacteria during kelp decay, shifting from alginate-degrading Gammaproteobacteria to fucoidan-degrading Verrucomicrobia, Planctomycetes, Kiritimatiellota, and Bacteroidetes. A model for the dynamic degradation of algal cell wall polysaccharides, a complex organic carbon, by epiphytic microbiota during kelp decay was proposed. This study deepens our understanding of the role of epiphytic bacteria in marine algal carbon cycling as well as pathogen control in algal culture.


Assuntos
Algas Comestíveis , Flavobacteriaceae , Kelp , Laminaria , Microbiota , Phaeophyceae , Humanos , Metagenoma , Kelp/metabolismo , Polissacarídeos/metabolismo , Alginatos/metabolismo , Flavobacteriaceae/genética , Flavobacteriaceae/metabolismo , Carbono/metabolismo
16.
Toxicol Appl Pharmacol ; 482: 116785, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070751

RESUMO

Phthalate esters (PAEs), accompanied by phthalate monoesters as hydrolysis metabolites in humans, have been widely used as plasticizers and exhibited disruptive effects on the endocrine and metabolic systems. The present study aims to investigate the inhibition behavior of PAEs and phthalate monoesters on the activity of the important hydrolytic enzymes, carboxylesterases (CESs), to elucidate the toxicity mechanism from a new perspective. The results showed significant inhibition on CES1 and CES2 by most PAEs, but not by phthalate monoesters, above which the activity of CES1 was strongly inhibited by DCHP, DEHP, DiOP, DiPP, DNP, DPP and BBZP, with inhibition ratios exceeding 80%. Kinetic analyses and in vitro-in vivo extrapolation were conducted, revealing that PAEs have the potential to disrupt the metabolism of endogenous substances catalyzed by CES1 in vivo. Molecular docking results revealed that hydrogen bonds and hydrophobic contacts formed by ester bonds contributed to the interaction of PAEs towards CES1. These findings will be beneficial for understanding the adverse effect of PAEs and phthalate monoesters.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Hidrolases de Éster Carboxílico , Simulação de Acoplamento Molecular , Ácidos Ftálicos/toxicidade , Plastificantes/toxicidade , Ésteres/química , Dibutilftalato , Dietilexilftalato/toxicidade , Dietilexilftalato/química , China
17.
Phys Rev Lett ; 132(17): 176601, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728716

RESUMO

The Yang-Lee edge singularity was originally studied from the standpoint of mathematical foundations of phase transitions. However, direct observation of anomalous scaling with the negative scaling dimension has remained elusive due to an imaginary magnetic field required for the nonunitary criticality. We experimentally implement an imaginary magnetic field with an open quantum system of heralded single photons, directly measure the partition function, and demonstrate the Yang-Lee edge singularity via the quantum-classical correspondence. We also demonstrate unconventional scaling laws for finite-temperature quantum dynamics.

18.
Phys Rev Lett ; 133(7): 070801, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213575

RESUMO

The non-Hermitian skin effect, by which the eigenstates of the Hamiltonian are predominantly localized at the boundary, has revealed a strong sensitivity of non-Hermitian systems to the boundary condition. Here we experimentally observe a striking boundary-induced dynamical phenomenon known as the non-Hermitian edge burst, which is characterized by a sharp boundary accumulation of loss in non-Hermitian time evolutions. In contrast to the eigenstate localization, the edge burst represents a generic non-Hermitian dynamical phenomenon that occurs in real time. Our experiment, based on photonic quantum walks, not only confirms the prediction of the phenomenon, but also unveils its complete space-time dynamics. Our observation of edge burst paves the way for studying the rich real-time dynamics in non-Hermitian topological systems.

19.
Chemistry ; 30(27): e202304369, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38414107

RESUMO

Single-molecule toroics (SMTs), defined as a type of molecules with toroidal arrangement of magnetic moment associated with bi-stable non-magnetic ground states, are promising candidates for high-density information storage and the development of molecule based multiferroic materials with linear magneto-electric coupling and multiferroic behavior. The design and synthesis of SMTs by arranging the magnetic anisotropy axis in a circular pattern at the molecular level have been of great interest to scientists for last two decades since the first detection of the SMT behavior in the seminal Dy3 molecules. DyIII ion has long been the ideal candidate for constructing SMTs due to its Kramer ion nature as well as high anisotropy. Nevertheless, other LnIII ions such as TbIII and HoIII ions, as well as some paramagnetic transition metal ions, have also been used to construct many nontraditional SMTs. Therefore, we review the progress in the studies of SMTs based on the nontraditional perspective, ranging from the 3D topological to 1D&2D&3D polymeric SMTs, and 3d-4f to non Dy-based SMTs. We hope the understanding we provide about nontraditional SMTs will be helpful in designing novel SMTs.

20.
BMC Cancer ; 24(1): 253, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395798

RESUMO

BACKGROUND: Cancer cachexia is associated with impaired functional and nutritional status and worse clinical outcomes. Global Leadership Initiative in Malnutrition (GLIM) consensus recommended the application of GLIM criteria to diagnose malnutrition in patients with cachexia. However, few previous study has applied the GLIM criteria in patients with cancer cachexia. METHODS: From July 2014 to May 2019, patients who were diagnosed with cancer cachexia and underwent radical gastrectomy for gastric cancer were included in this study. Malnutrition was diagnosed using the GLIM criteria. Skeletal muscle index was measured using abdominal computed tomography (CT) images at the third lumbar vertebra (L3) level. Hand-grip strength and 6-meters gait speed were measured before surgery. RESULTS: A total of 356 patients with cancer cachexia were included in the present study, in which 269 (75.56%) were identified as having malnutrition based on the GLIM criteria. GLIM-defined malnutrition alone did not show significant association with short-term postoperative outcomes, including complications, costs or length of postoperative hospital stays. The combination of low hand-grip strength or low gait speed with GLIM-defined malnutrition led to a significant predictive value for these outcomes. Moreover, low hand-grip strength plus GLIM-defined malnutrition was independently associated with postoperative complications (OR 1.912, 95% CI 1.151-3.178, P = 0.012). GLIM-defined malnutrition was an independent predictive factor for worse OS (HR 2.310, 95% CI 1.421-3.754, P = 0.001) and DFS (HR 1.815, 95% CI 1.186-2.779, P = 0.006) after surgery. The addition of low hand-grip strength or low gait speed to GLIM-defined malnutrition did not increase its predictive value for survival. CONCLUSION: GLIM-defined malnutrition predicted worse long-term survival in gastric cancer patients with cachexia. Gait speed and hand-grip strength added prognostic value to GLIM-defined malnutrition for the prediction of short-term postoperative outcomes, which could be incorporated into preoperative assessment protocols in patients with cancer cachexia.


Assuntos
Desnutrição , Neoplasias Gástricas , Humanos , Caquexia/diagnóstico , Caquexia/etiologia , Prognóstico , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Liderança , Velocidade de Caminhada , Desnutrição/complicações , Desnutrição/diagnóstico , Estado Nutricional , Força da Mão , Avaliação Nutricional
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