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1.
Cell ; 160(6): 1246-60, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25748654

RESUMO

Genetic screens are powerful tools for identifying genes responsible for diverse phenotypes. Here we describe a genome-wide CRISPR/Cas9-mediated loss-of-function screen in tumor growth and metastasis. We mutagenized a non-metastatic mouse cancer cell line using a genome-scale library with 67,405 single-guide RNAs (sgRNAs). The mutant cell pool rapidly generates metastases when transplanted into immunocompromised mice. Enriched sgRNAs in lung metastases and late-stage primary tumors were found to target a small set of genes, suggesting that specific loss-of-function mutations drive tumor growth and metastasis. Individual sgRNAs and a small pool of 624 sgRNAs targeting the top-scoring genes from the primary screen dramatically accelerate metastasis. In all of these experiments, the effect of mutations on primary tumor growth positively correlates with the development of metastases. Our study demonstrates Cas9-based screening as a robust method to systematically assay gene phenotypes in cancer evolution in vivo.


Assuntos
Sistemas CRISPR-Cas , Carcinoma Pulmonar de Células não Pequenas/genética , Técnicas de Inativação de Genes , Neoplasias Pulmonares/genética , Metástase Neoplásica/genética , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudo de Associação Genômica Ampla , Humanos , Neoplasias Pulmonares/patologia , Camundongos , RNA Guia de Cinetoplastídeos
2.
Nature ; 602(7896): 268-273, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110736

RESUMO

Genetic risk for autism spectrum disorder (ASD) is associated with hundreds of genes spanning a wide range of biological functions1-6. The alterations in the human brain resulting from mutations in these genes remain unclear. Furthermore, their phenotypic manifestation varies across individuals7,8. Here we used organoid models of the human cerebral cortex to identify cell-type-specific developmental abnormalities that result from haploinsufficiency in three ASD risk genes-SUV420H1 (also known as KMT5B), ARID1B and CHD8-in multiple cell lines from different donors, using single-cell RNA-sequencing (scRNA-seq) analysis of more than 745,000 cells and proteomic analysis of individual organoids, to identify phenotypic convergence. Each of the three mutations confers asynchronous development of two main cortical neuronal lineages-γ-aminobutyric-acid-releasing (GABAergic) neurons and deep-layer excitatory projection neurons-but acts through largely distinct molecular pathways. Although these phenotypes are consistent across cell lines, their expressivity is influenced by the individual genomic context, in a manner that is dependent on both the risk gene and the developmental defect. Calcium imaging in intact organoids shows that these early-stage developmental changes are followed by abnormal circuit activity. This research uncovers cell-type-specific neurodevelopmental abnormalities that are shared across ASD risk genes and are finely modulated by human genomic context, finding convergence in the neurobiological basis of how different risk genes contribute to ASD pathology.


Assuntos
Transtorno do Espectro Autista , Predisposição Genética para Doença , Neurônios , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/patologia , Córtex Cerebral/citologia , Proteínas de Ligação a DNA/genética , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/patologia , Histona-Lisina N-Metiltransferase/genética , Humanos , Neurônios/classificação , Neurônios/metabolismo , Neurônios/patologia , Organoides/citologia , Proteômica , RNA-Seq , Análise de Célula Única , Fatores de Transcrição/genética
3.
Nature ; 610(7933): 661-666, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198794

RESUMO

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

4.
Nature ; 608(7923): 586-592, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35859170

RESUMO

The ability to associate temporally segregated information and assign positive or negative valence to environmental cues is paramount for survival. Studies have shown that different projections from the basolateral amygdala (BLA) are potentiated following reward or punishment learning1-7. However, we do not yet understand how valence-specific information is routed to the BLA neurons with the appropriate downstream projections, nor do we understand how to reconcile the sub-second timescales of synaptic plasticity8-11 with the longer timescales separating the predictive cues from their outcomes. Here we demonstrate that neurotensin (NT)-expressing neurons in the paraventricular nucleus of the thalamus (PVT) projecting to the BLA (PVT-BLA:NT) mediate valence assignment by exerting NT concentration-dependent modulation in BLA during associative learning. We found that optogenetic activation of the PVT-BLA:NT projection promotes reward learning, whereas PVT-BLA projection-specific knockout of the NT gene (Nts) augments punishment learning. Using genetically encoded calcium and NT sensors, we further revealed that both calcium dynamics within the PVT-BLA:NT projection and NT concentrations in the BLA are enhanced after reward learning and reduced after punishment learning. Finally, we showed that CRISPR-mediated knockout of the Nts gene in the PVT-BLA pathway blunts BLA neural dynamics and attenuates the preference for active behavioural strategies to reward and punishment predictive cues. In sum, we have identified NT as a neuropeptide that signals valence in the BLA, and showed that NT is a critical neuromodulator that orchestrates positive and negative valence assignment in amygdala neurons by extending valence-specific plasticity to behaviourally relevant timescales.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Aprendizagem , Vias Neurais , Neurotensina , Punição , Recompensa , Complexo Nuclear Basolateral da Amígdala/citologia , Complexo Nuclear Basolateral da Amígdala/fisiologia , Cálcio/metabolismo , Sinais (Psicologia) , Plasticidade Neuronal , Neurotensina/metabolismo , Optogenética , Núcleos Talâmicos/citologia , Núcleos Talâmicos/fisiologia
5.
Am J Hum Genet ; 110(10): 1750-1768, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37802044

RESUMO

Whole-exome sequencing of autism spectrum disorder (ASD) probands and unaffected family members has identified many genes harboring de novo variants suspected to play a causal role in the disorder. Of these, chromodomain helicase DNA-binding protein 8 (CHD8) is the most recurrently mutated. Despite the prevalence of CHD8 mutations, we have little insight into how CHD8 loss affects genome organization or the functional consequences of these molecular alterations in neurons. Here, we engineered two isogenic human embryonic stem cell lines with CHD8 loss-of-function mutations and characterized differences in differentiated human cortical neurons. We identified hundreds of genes with altered expression, including many involved in neural development and excitatory synaptic transmission. Field recordings and single-cell electrophysiology revealed a 3-fold decrease in firing rates and synaptic activity in CHD8+/- neurons, as well as a similar firing-rate deficit in primary cortical neurons from Chd8+/- mice. These alterations in neuron and synapse function can be reversed by CHD8 overexpression. Moreover, CHD8+/- neurons displayed a large increase in open chromatin across the genome, where the greatest change in compaction was near autism susceptibility candidate 2 (AUTS2), which encodes a transcriptional regulator implicated in ASD. Genes with changes in chromatin accessibility and expression in CHD8+/- neurons have significant overlap with genes mutated in probands for ASD, intellectual disability, and schizophrenia but not with genes mutated in healthy controls or other disease cohorts. Overall, this study characterizes key molecular alterations in genome structure and expression in CHD8+/- neurons and links these changes to impaired neuronal and synaptic function.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Animais , Camundongos , Transtorno Autístico/genética , Transtorno do Espectro Autista/genética , Cromatina/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Expressão Gênica , Fatores de Transcrição/genética
6.
Plant Cell ; 35(1): 409-434, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36222567

RESUMO

Fluctuations in nitrogen (N) availability influence protein and starch levels in maize (Zea mays) seeds, yet the underlying mechanism is not well understood. Here, we report that N limitation impacted the expression of many key genes in N and carbon (C) metabolism in the developing endosperm of maize. Notably, the promoter regions of those genes were enriched for P-box sequences, the binding motif of the transcription factor prolamin-box binding factor 1 (PBF1). Loss of PBF1 altered accumulation of starch and proteins in endosperm. Under different N conditions, PBF1 protein levels remained stable but PBF1 bound different sets of target genes, especially genes related to the biosynthesis and accumulation of N and C storage products. Upon N-starvation, the absence of PBF1 from the promoters of some zein genes coincided with their reduced expression, suggesting that PBF1 promotes zein accumulation in the endosperm. In addition, PBF1 repressed the expression of sugary1 (Su1) and starch branching enzyme 2b (Sbe2b) under normal N supply, suggesting that, under N-deficiency, PBF1 redirects the flow of C skeletons for zein toward the formation of C compounds. Overall, our study demonstrates that PBF1 modulates C and N metabolism during endosperm development in an N-dependent manner.


Assuntos
Endosperma , Zeína , Endosperma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/metabolismo , Proteínas de Plantas/metabolismo , Prolaminas/genética , Zeína/genética , Zeína/metabolismo , Nitrogênio/metabolismo , Amido/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Fish Shellfish Immunol ; 148: 109521, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552889

RESUMO

In mammals, ß-catenin participates in innate immune process through interaction with NF-κB signaling pathway. However, its role in teleost immune processes remains largely unknown. We aimed to clarify the function of ß-catenin in the natural defense mechanism of Qi river crucian carp (Carassius auratus). ß-catenin exhibited a ubiquitous expression pattern in adult fish, as indicated by real-time PCR analysis. Following lipopolysaccharide (LPS), Polyinosinic-polycytidylic acid (polyI: C) and Aeromonas hydrophila (A. hydrophila) challenges, ß-catenin increased in gill, intestine, liver and kidney, indicating that ß-catenin likely plays a pivotal role in the immune response against pathogen infiltration. Inhibition of the ß-catenin pathway using FH535, an inhibitor of Wnt/ß-catenin pathway, resulting in pathological damage of the gill, intestine, liver and kidney, significant decrease of innate immune factors (C3, defb3, LYZ-C, INF-γ), upregulation of inflammatory factors (NF-κB, TNF-α, IL-1, IL-8), and downregulation of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) activities, increase of Malondialdehyde (MDA) content. Following A. hydrophila invasion, the mortality rate in the FH535 treatment group exceeded that of the control group. In addition, the diversity of intestinal microflora decreased and the community structure was uneven after FH535 treatment. In summary, our findings strongly suggest that ß-catenin plays a vital role in combating pathogen invasion and regulating intestinal flora in Qi river crucian carp.


Assuntos
Carpas , Doenças dos Peixes , Microbioma Gastrointestinal , Infecções por Bactérias Gram-Negativas , Sulfonamidas , Animais , Carpa Dourada/genética , Carpa Dourada/metabolismo , Carpas/genética , Carpas/metabolismo , NF-kappa B , Rios , beta Catenina/genética , Qi , Imunidade Inata/genética , Antioxidantes , Aeromonas hydrophila/fisiologia , Proteínas de Peixes , Infecções por Bactérias Gram-Negativas/veterinária , Mamíferos/metabolismo
8.
J Fish Biol ; 104(6): 1836-1847, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38488309

RESUMO

The skin color of the large yellow croaker (Larimichthys crocea) is a crucial indicator to determine its economic value. However, the location of pigment cells in the skin structure is uncertain. To determine the pigment cell type in the skin, the vertical order and ultrastructure of pigment cells were examined using light microscopy and transmission electron microscopy. Both dorsal and ventral skins comprise the epidermis, dermis, and hypodermis. Xanthophores, melanophores, and iridophores were observed in the dermis of the dorsal skin, whereas the latter two were in the dermis of the ventral skin. Interestingly, the size of xanthophores in the dorsal skin was significantly smaller than that of xanthophores in the ventral skin; however, the density of dorsal xanthophores was significantly higher than that of ventral xanthophores. The type L-iridophores with large crystalline structures were observed in the uppermost area of the upper pigment layer, which contributed to the strikingly metallic luster shown by the ventral skin. The melanophores were exclusively found in the dorsal skin, offering the purpose of camouflage. Taken together, our results indicated that the pigment cells display different arrangement patterns between dorsal and ventral skin, and the golden color in the ventral skin results from the coexistence of light-reflecting iridophores and light-absorbing xanthophores.


Assuntos
Microscopia Eletrônica de Transmissão , Perciformes , Pigmentação da Pele , Pele , Animais , Perciformes/anatomia & histologia , Pele/ultraestrutura , Melanóforos/ultraestrutura
9.
World Dev ; 1822024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39328830

RESUMO

Global food prices rose substantially after the start of the COVID-19 pandemic. This paper examines the impact of rising food prices during the pandemic on food security in Burkina Faso. We aim to answer two primary questions. First, how do food price shocks affect household food insecurity? Second, what coping strategies do households adopt in response to these price shocks? Leveraging country-wide high-frequency longitudinal data, we employ household fixed effect models to examine the effects. In the absence of direct information on local food prices, we use household-reported price shocks to capture province-level price increases and show that the results are consistent with national-level price increases. We find significant and immediate increases in food insecurity following the price shocks, and this effect persists for at least two months. The price shocks most acutely affected the poorest households. Furthermore, food insecurity increased more in rural areas than in urban areas. The higher proportion of poorer households in rural areas explains part of this difference. We find that households primarily cope with the shock by relying on increased assistance from relatives in Burkina Faso and abroad. This study is the first to use panel data with household fixed effects to examine the repercussions of the rise in food prices during the pandemic on food insecurity in a developing country and to examine the coping mechanisms employed by households. Given that food prices are likely to remain high globally for an extended period, our findings carry implications for the broader developing world. Furthermore, given the disproportionate effect on the poorest and those living in rural areas, the findings highlight the need for policies to mitigate the negative impacts of the price shocks and enhance overall food security in countries like Burkina Faso.

10.
Fish Physiol Biochem ; 50(2): 705-719, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38294642

RESUMO

Color changes and pattern formations can represent strategies of the utmost importance for the survival of individuals or of species. Previous studies have associated capture with the formation of blotches (areas with light color) of coral trout, but the regulatory mechanisms link the two are lacking. Here, we report that capture induced blotches formation within 4-5 seconds. The blotches disappeared after anesthesia dispersed the pigment cells and reappeared after electrical stimulation. Subsequently, combining immunofluorescence, transmission electron microscopy and chemical sympathectomy, we found blotches formation results from activation of catecholaminergic neurons below the pigment layer. Finally, the in vitro incubation and intraperitoneal injection of norepinephrine (NE) induced aggregation of chromatosomes and lightening of body color, respectively, suggesting that NE, a neurotransmitter released by catecholaminergic nerves, mediates blotches formation. Our results demonstrate that acute stress response-induced neuronal activity can drive rapid changes in body color, which enriches our knowledge of physiological adaptations in coral reef fish.


Assuntos
Antozoários , Bass , Animais , Truta , Norepinefrina/farmacologia , Bass/fisiologia , Recifes de Corais
11.
Water Sci Technol ; 90(4): 1099-1114, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39215726

RESUMO

The transport of solid-liquid two-phase flow is widely used in water conservancy, environmental protection, and municipal engineering. Accurate pressure loss calculation is crucial for hydraulic transport pipelines, particularly in the case of bends, valves, and other deformation parts. These factors directly impact the energy consumption and the investment of the system. This paper employed the Euler-Euler multiphase flow model to investigate the characteristics of solid-liquid two-phase flow in vertically positioned combined elbows. The model was initially validated using data from the literature. Subsequently, based on the validated model, an investigation was conducted to determine the relationship between pressure loss and various factors, including flow velocity, combined angle, particle concentration, and particle size. Finally, the changes in velocity distribution, particle concentration, and turbulent kinetic energy were analyzed. The results indicate that the pressure loss increases with the flow velocity, tends to decrease with the combined angle, and increases with the particle concentration. The relationship between pressure loss and particle size is more complex. The velocity distribution, particle concentration, and turbulent kinetic energy exhibit the variations caused by different factors.


Assuntos
Modelos Teóricos , Pressão , Tamanho da Partícula , Movimentos da Água , Simulação por Computador
12.
Plant Cell Physiol ; 64(10): 1146-1158, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37540575

RESUMO

Auxin plays an essential role in modulating leaf development. However, its role in leaf development in rice (Oryza sativa L.) remains largely unknown. In this study, we found that PINOID (OsPID) and two Sister-of-PIN1s, termed PIN-FORMED1c (OsPIN1c) and OsPIN1d, are necessary for rice leaf development. The ospin1c ospin1d null mutant lines presented severe defects in leaf morphogenesis, including drooping and semi-drooping blades, an abnormally thickened sheath and lamina joint, and fused leaves with absent ligules and auricles. Loss-of-function ospid mutants displayed generally similar leaf morphology but lacked leaf fusion. Interestingly, misshaped leaf genesis displayed a preference for being ipsilateral. In addition, OsPIN1c and OsPID were commonly localized in the initiating leaf primordia. Furthermore, accompanied by the more severe organ morphogenesis in the ospin1c ospin1d ospid triple mutant, RNA sequencing analysis revealed that many genes essential for leaf development have an altered expression level. Together, this study furthers our understanding of the role auxin transport plays during leaf development in monocot rice.


Assuntos
Oryza , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oryza/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Ácidos Indolacéticos/metabolismo , Morfogênese/genética
13.
Opt Lett ; 48(23): 6088-6091, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039198

RESUMO

In this Letter, we propose a novel, to the best of our knowledge, dual-mode tunable absorber that utilizes quasi-bound states in the continuum (q-BIC) based on the periodically arranged silicon cylinders tetramer. By introducing asymmetry perturbation through manipulating the diameters of diagonal cylinders in the all-dielectric structure, the symmetry-protected BIC (SP-BIC) transforms into q-BIC, leading to the emergence of one transmission and one reflection Fano-like resonant mode. The relationship between the quality factor of each mode and the asymmetry parameter α is analyzed, revealing an exponential dependence with an exponent of -1.75, i.e., Q ∝ α-1.75. To explain the underlying physics, multipole decomposition analysis and Aleksandra's theory are applied. Subsequently, a monolayer graphene is introduced to the all-dielectric structure to demonstrate the application of the dual-mode tunable absorber. When the critical coupling condition is satisfied, each mode can achieve the theoretical maximum absorption, demonstrating the distinctive capability of our proposed absorber for tuning and efficient light absorption. This research provides valuable insights into light-matter interactions and opens up possibilities for optical modulation and the development of graphene-based devices.

14.
Cancer Cell Int ; 23(1): 246, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858068

RESUMO

BACKGROUND: RAD51B plays a significant role in homologous recombination-mediated repair of DNA double-strand breaks. Many enhancer variants are involved in cancer development and progression. However, the significance of enhancer variants of RAD51B in glioma susceptibility and progression remains unclear. METHODS: A case-control study consisting of 1056 individuals was conducted to evaluate the associations of enhancer variants of RAD51B with glioma susceptibility and progression. Sequenom MassARRAY technology was used for genotyping. The function of enhancer variants was explored by biochemical assays. RESULTS: A significantly decreased risk of glioma was associated with rs6573816 GC genotype compared with rs6573816 GG genotype (OR = 0.66, 95% CI 0.45-0.97; P = 0.034). Multivariable Cox regression revealed that rs6573816 was significantly associated with glioma progression in a sex-dependent manner. Worse PFS was found in the male patients with high grade glioma carrying rs6573816 GC or CC genotype (HR = 2.28, 95% CI 1.14-4.57; P = 0.020). The rs6573816 C allele repressed enhancer activity by affecting transcription factor POU2F1 binding, which resulted in lower expression of RAD51B. Remarkably attenuated expression of RAD51B was observed following POU2F1 knockdown. Consistently, positive correlation between the expression of POU2F1 and RAD51B was found in lymphoblastic cells and glioma tissues. CONCLUSIONS: These results indicate that an enhancer variant of RAD51B rs6573816 influences enhancer activity by changing a POU2F1 binding site and confers susceptibility and progression to glioma.

15.
Ann Bot ; 131(6): 953-966, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37177810

RESUMO

BACKGROUND AND AIMS: Hybridization has long been recognized as an important process for plant evolution and is often accompanied by polyploidization, another prominent force in generating biodiversity. Despite its pivotal importance in evolution, the actual prevalence and distribution of hybridization across the tree of life remain unclear. METHODS: We used whole-genome shotgun (WGS) sequencing and cytological data to investigate the evolutionary history of Henckelia, a large genus in the family Gesneriaceae with a high frequency of suspected hybridization and polyploidization events. We generated WGS sequencing data at about 10× coverage for 26 Chinese Henckelia species plus one Sri Lankan species. To untangle the hybridization history, we separately extracted whole plastomes and thousands of single-copy nuclear genes from the sequencing data, and reconstructed phylogenies based on both nuclear and plastid data. We also explored sources of both genealogical and cytonuclear conflicts and identified signals of hybridization and introgression within our phylogenomic dataset using several statistical methods. Additionally, to test the polyploidization history, we evaluated chromosome counts for 45 populations of the 27 Henckelia species studied. KEY RESULTS: We obtained well-supported phylogenetic relationships using both concatenation- and coalescent-based methods. However, the nuclear phylogenies were highly inconsistent with the plastid phylogeny, and we observed intensive discordance among nuclear gene trees. Further analyses suggested that both incomplete lineage sorting and gene flow contributed to the observed cytonuclear and genealogical discordance. Our analyses of introgression and phylogenetic networks revealed a complex history of hybridization within the genus Henckelia. In addition, based on chromosome counts for 27 Henckelia species, we found independent polyploidization events occurred within Henckelia after different hybridization events. CONCLUSIONS: Our findings demonstrated that hybridization and polyploidization are common in Henckelia. Furthermore, our results revealed that H. oblongifolia is not a member of the redefined Henckelia and they suggested several other taxonomic treatments in this genus.


Assuntos
Núcleo Celular , Hibridização Genética , Filogenia , Núcleo Celular/genética , Plastídeos/genética , Fluxo Gênico
16.
Bioorg Chem ; 134: 106451, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907048

RESUMO

Cytotoxic peptides derived from spider venoms have been considered as promising candidates for anticancer treatment. The novel cell penetrating peptide LVTX-8, which is a 25-residue amphipathic α-helical peptide isolated from spider Lycosa vittata, exhibited potent cytotoxicity and is a potential precursor for further anticancer drug development. Nevertheless, LVTX-8 may be easily degraded by multiple proteases, inducing the proteolytic stability problem and short half-life. In this study, ten LVTX-8-based analogs were rationally designed and the efficient manual synthetic method was established by the DIC/Oxyma based condensation system. The cytotoxicity of synthetic peptides was systematically evaluated against seven cancer cell lines. Seven of the derived peptides exhibited high cytotoxicity towards tested cancer in vitro, which was better than or comparable to that of natural LVTX-8. In particular, both N-acetyl and C-hydrazide modified LVTX-8 (825) and the conjugate methotrexate (MTX)-GFLG-LVTX-8 (827) possessed more durable anticancer efficiency, higher proteolytic stability, as well as lower hemolysis. Finally, we confirmed that LVTX-8 could disrupt the integrity of cell membrane, target the mitochondria and reduce the mitochondrial membrane potential to induce the cell death. Taken together, the structural modifications were conducted on LVTX-8 for the first time and the stability significantly improved derivatives 825 and 827 may provide useful references for the modifications of cytotoxic peptides.


Assuntos
Antineoplásicos , Peptídeos Penetradores de Células , Neoplasias , Venenos de Aranha , Humanos , Venenos de Aranha/farmacologia , Venenos de Aranha/química , Venenos de Aranha/metabolismo , Antineoplásicos/farmacologia , Metotrexato/química , Peptídeos Penetradores de Células/química
17.
Brain Behav Evol ; 98(3): 124-147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36543150

RESUMO

Mudskippers are intertidal burrowing fish with unique living habits. So far, studies on the cytoarchitecture of the brain in fish with such behaviors remain limited. Therefore, documenting the neuroanatomy of this animal is of interest because of its unique characteristics. In this study, we examined the cytoarchitecture of mudskipper (Boleophthalmus pectinirostris) brain and investigated whether it has any peculiarities in its brain structures. In general, the basic composition, morphology, and organization of mudskipper brain do not vary markedly from those of other teleosts. The main differences appear in the telencephalon and diencephalon. In addition to Nissl staining, immunostainings for catecholaminergic and cholinergic systems were performed to help identify certain nuclei. The results showed that the number of subdivisions of the central division of pallium, lateral division of pallium, and medial division of pallium were different with other teleost species. In addition, some diencephalic nuclei, including the nucleus subglomerulosus, lateral thalamic nucleus, and intermediate superficial pretectal nucleus, were absent, which suggests the corresponding functions, such as visual or gustatory function, are less developed or specialized in B. pectinirostris. These results will provide a fundamental neuroanatomical basis for future studies on neuroendocrine regulation of behavior in intertidal burrowing fish.


Assuntos
Encéfalo , Peixes , Animais , Peixes/fisiologia
18.
Plant Cell Rep ; 42(7): 1217-1231, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148321

RESUMO

KEY MESSAGE: The transcription elongation factor SPT4/SPT5 complex is essential for rice vegetative and reproductive growth and that OsSPT5-1, with its interactor APO2, is involved in multiple phytohormone pathways. The SPT4/SPT5 complex is a transcription elongation factor that regulates the processivity of transcription elongation. However, our understanding of the role of SPT4/SPT5 complex in developmental regulation remains limited. Here, we identified three SPT4/SPT5 genes (OsSPT4, OsSPT5-1, and OsSPT5-2) in rice, and investigated their roles in vegetative and reproductive growth. These genes are highly conserved with their orthologs in other species. OsSPT4 and OsSPT5-1 are widely expressed in various tissues. By contrast, OsSPT5-2 is expressed at a relatively low level, which could cause osspt5-2 null mutants have no phenotypes. Loss-of-function mutants of OsSPT4 and OsSPT5-1 could not be obtained; their heterozygotes showed severe reproductive growth defects. An incomplete mutant line (osspt5-1#12) displayed gibberellin-related dwarfed defects and a weak root system at an early vegetative phase, and a short life cycle in different planting environments. Furthermore, OsSPT5-1 interacts with the transcription factor ABERRANT PANICLE ORGANIZATION 2 (APO2) and plays a similar role in regulating the growth of rice shoots. RNA sequencing analysis verified that OsSPT5-1 is involved in multiple phytohormone pathways, including gibberellin, auxin, and cytokinin. Therefore, the SPT4/SPT5 complex is essential for both vegetative and reproductive growth in rice.


Assuntos
Oryza , Proteínas de Saccharomyces cerevisiae , Oryza/genética , Oryza/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Reguladores de Crescimento de Plantas , Giberelinas , Fatores de Transcrição/genética , Crescimento e Desenvolvimento , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Transcrição Gênica
19.
Gynecol Endocrinol ; 39(1): 2266504, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37798837

RESUMO

The aim of this study was to investigate the effects of positive anti-thyroid peroxidase (TPO) antibodies on fertility, embryo quality, and pregnancy outcomes in women with normal thyroid function. A cross-sectional study of 1223 infertile women who received assisted reproductive technology (ART) treatment for the first time was conducted at our hospital from January 2019 to March 2022. Overall, 263 infertile women were included, comprising 263 cycles and 1813 embryos, and were divided into a positive group and a control group based on TPO antibody levels. The positive group was further divided into two subgroups according to the median antibody titer, and the therapeutic indices and pregnancy outcomes for each group were compared. The results showed that the AMH level in the positive group was significantly lower than that in the control group (2.37 (1.26-3.63) ng/ml vs. 3.54 (1.74-5.41) ng/ml, p < 0.001). The high-quality embryo rate (40.04% vs. 45.49%, p = 0.034) and live birth rate (23.26% vs. 36.16, p = 0.035) of the positive group were lower than those of the control group; the miscarriage rate was higher than that of the control group (37.50% vs. 17.95%, p = 0.035). The live birth rate in the low-titer group was significantly higher than that in the high-titer group (32.56% vs. 13.95%, p = 0.041). Studies have shown that positive anti-thyroid peroxidase antibodies are associated with a decreased ovarian reserve and decreased embryo quality. High titers of anti-thyroid peroxidase antibodies can reduce the live birth rate.


Assuntos
Infertilidade Feminina , Reserva Ovariana , Gravidez , Feminino , Humanos , Infertilidade Feminina/terapia , Injeções de Esperma Intracitoplásmicas , Estudos Transversais , Técnicas de Reprodução Assistida , Taxa de Gravidez , Estudos Retrospectivos , Fertilização in vitro/métodos
20.
Phytochem Anal ; 34(1): 56-66, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36208087

RESUMO

INTRODUCTION: Apocyni Veneti Folium (AVF) is a commonly used traditional Chinese medicinal herb for the treatment of hypertension. Chemical markers are crucial for the quality control of herbal medicines; however, the therapeutic components of AVF remain to be well elucidated. OBJECTIVES: This study was intended to integrate serum pharmacochemistry and network pharmacology to identify chemical markers of AVF and establish an efficacy-related quality control method of AVF. MATERIAL AND METHODS: Ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) was applied to identify the absorbed AVF constituents in rat serum. Network pharmacology was further used to identify anti-hypertension-related chemical markers. Subsequently, a quantitative method was established using UPLC with diode array detection (DAD) and applied for quality evaluation of commercial AVF samples. RESULTS: Thirteen prototype constituents were unequivocally or tentatively characterized in serum samples, among which quercetin, kaempferol, hyperoside, isoquercitrin, chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid were identified as dominant chemicals related to anti-hypertensive efficacy. The quantitative data showed that the total contents of seven marker components even showed 2-fold variation among 14 batches of commercial AVF samples with RSD values ranging from 12.15% to 75.61%. Hierarchical cluster analysis and heatmap analysis showed that 14 batches of commercial AVF samples could be divided into three main groups. CONCLUSION: The chemical markers obtained from this study could be applicable for efficacy-related quality control of AVF.


Assuntos
Medicamentos de Ervas Chinesas , Flavonoides , Ratos , Animais , Flavonoides/análise , Espectrometria de Massas em Tandem , Farmacologia em Rede , Controle de Qualidade , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química
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