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1.
PLoS Genet ; 18(11): e1010521, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36409768

RESUMO

A family of giant KASH proteins, including C. elegans ANC-1 and mammalian Nesprin-1 and -2, are involved in organelle anchoring and are associated with multiple neurodevelopmental disorders including autism, bipolar disorder, and schizophrenia. However, little is known about how these proteins function in neurons. Moreover, the role of organelle anchoring in axon development is poorly understood. Here, we report that ANC-1 functions with the SLT-1 extracellular guidance cue to polarize ALM axon growth. This role for ANC-1 is specific to its longer ANC-1A and ANC-1C isoforms, suggesting that it is mechanistically distinct from previously described roles for ANC-1. We find that ANC-1 is required for the localization of a cluster of mitochondria to the base of the proximal axon. Furthermore, genetic and pharmacological studies indicate that ANC-1 functions with mitochondria to promote polarization of ALM axon growth. These observations reveal a mechanism whereby ANC-1 functions through mitochondria to polarize axon growth in response to SLT-1.


Assuntos
Proteínas de Caenorhabditis elegans , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Axônios/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mamíferos/metabolismo , Proteínas dos Microfilamentos/metabolismo
2.
Org Biomol Chem ; 18(34): 6732-6737, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32832956

RESUMO

A nitrate-promoted Pd-catalysed mild cross-dehydrogenative C(sp2)-H bond oxidation of oximes or azobenzenes with diverse carboxylic acids has been developed. In contrast to the previous catalytic systems, this protocol features mild conditions (close to room temperature for most cases) and a broad substrate scope (up to 64 examples), thus constituting a versatile method to directly prepare diverse O-aryl esters. Moreover, the superiority of the nitrate additive in this mild transformation was further determined by experimental and computational evidence.

4.
Angew Chem Int Ed Engl ; 57(43): 14085-14089, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30161283

RESUMO

Selective introduction of fluorine into molecules by the cleavage of inert C-H bonds is of central academic and synthetic interest, yet remains challenging. Given the central role of alcohols in organic chemistry as the most ubiquitous building blocks, a versatile and selective C(sp3 )-H and C(sp2 )-H fluorination of simple alcohols, enabled by novel designed exo-directing groups, is described. C(sp2 )-H bond fluorination was achieved by using a simple acetone oxime as auxiliary, whereas a new, modular and easily accessible bidentate auxiliary was developed for the efficient and site-selective fluorination of various primary methyl, methylene, and benzylic C(sp3 )-H bonds. Fluorinated alcohols can readily be accessed by the removal of auxiliaries, and significantly expands the synthetic prospect of the present procedure.

5.
Plant J ; 84(6): 1274-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26603028

RESUMO

Salt stress from soil or irrigation water limits plant growth. A T-DNA insertion mutant in C24, named athspr (Arabidopsis thaliana heat shock protein-related), showed several phenotypes, including reduced organ size and enhanced sensitivity to environmental cues. The athspr mutant is severely impaired under salinity levels at which wild-type (WT) plants grow normally. AtHSPR encodes a nuclear-localized protein with ATPase activity, and its expression was enhanced by high salinity and abscisic acid (ABA). Overexpression (OE) of AtHSPR significantly enhanced tolerance to salt stress by increasing the activities of the antioxidant system and by maintaining K(+) /Na(+) homeostasis. Quantitative RT-PCR analyses showed that OE of AtHSPR increased the expression of ABA/stress-responsive, salt overly sensitive (SOS)-related and antioxidant-related genes. In addition, ABA content was reduced in athspr plants with or without salt stress, and exogenous ABA restored WT-like salt tolerance to athspr plants. athspr exhibited increased leaf stomatal density and stomatal index, slower ABA-induced stomatal closure and reduced drought tolerance relative to the WT. AtHSPR OE enhanced drought tolerance by reducing leaf water loss and stomatal aperture. Transcript profiling in athspr showed a differential salt-stress response for genes involved in accumulation of reactive oxygen species (ROS), ABA signaling, cell death, stress response and photosynthesis. Taken together, our results suggested that AtHSPR is involved in salt tolerance in Arabidopsis through modulation of ROS levels, ABA-dependent stomatal closure, photosynthesis and K(+) /Na(+) homeostasis.


Assuntos
Ácido Abscísico/metabolismo , Adenosina Trifosfatases/metabolismo , Antioxidantes/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Tolerância ao Sal , Adenosina Trifosfatases/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Homeostase , Fotossíntese/fisiologia , Estômatos de Plantas/fisiologia , Potássio/metabolismo , Espécies Reativas de Oxigênio , Sódio/metabolismo , Estresse Fisiológico/fisiologia , Água
6.
J Cell Biol ; 223(5)2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38470363

RESUMO

Mitochondria transport is crucial for axonal mitochondria distribution and is mediated by kinesin-1-based anterograde and dynein-based retrograde motor complexes. While Miro and Milton/TRAK were identified as key adaptors between mitochondria and kinesin-1, recent studies suggest the presence of additional mechanisms. In C. elegans, ric-7 is the only single gene described so far, other than kinesin-1, that is absolutely required for axonal mitochondria localization. Using CRISPR engineering in C. elegans, we find that Miro is important but is not essential for anterograde traffic, whereas it is required for retrograde traffic. Both the endogenous RIC-7 and kinesin-1 act at the leading end to transport mitochondria anterogradely. RIC-7 binding to mitochondria requires its N-terminal domain and partially relies on MIRO-1, whereas RIC-7 accumulation at the leading end depends on its disordered region, kinesin-1, and metaxin2. We conclude that transport complexes containing kinesin-1 and RIC-7 polarize at the leading edge of mitochondria and are required for anterograde axonal transport in C. elegans.


Assuntos
Transporte Axonal , Cinesinas , Animais , Axônios , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Cinesinas/metabolismo , Mitocôndrias/metabolismo
7.
Sci Data ; 11(1): 463, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714688

RESUMO

Adverse perinatal factors can interfere with the normal development of the brain, potentially resulting in long-term effects on the comprehensive development of children. Presently, the understanding of cognitive and neurodevelopmental processes under conditions of adverse perinatal factors is substantially limited. There is a critical need for an open resource that integrates various perinatal factors with the development of the brain and mental health to facilitate a deeper understanding of these developmental trajectories. In this Data Descriptor, we introduce a multicenter database containing information on perinatal factors that can potentially influence children's brain-mind development, namely, periCBD, that combines neuroimaging and behavioural phenotypes with perinatal factors at county/region/central district hospitals. PeriCBD was designed to establish a platform for the investigation of individual differences in brain-mind development associated with perinatal factors among children aged 3-10 years. Ultimately, our goal is to help understand how different adverse perinatal factors specifically impact cognitive development and neurodevelopment. Herein, we provide a systematic overview of the data acquisition/cleaning/quality control/sharing, processes of periCBD.


Assuntos
Encéfalo , Desenvolvimento Infantil , Criança , Pré-Escolar , Humanos , Encéfalo/crescimento & desenvolvimento , Encéfalo/diagnóstico por imagem , China , Cognição , Bases de Dados Factuais , Neuroimagem
8.
Medicine (Baltimore) ; 102(32): e34531, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37565911

RESUMO

INTRODUCTION: Sebaceous carcinoma of the eyelid is the third most common eyelid malignancy, after basal cell carcinoma and squamous cell carcinoma. It is highly malignant and potentially aggressive. Surgical excision is currently the best treatment option for this condition. Patients often require reconstruction surgery to repair eyelid defects to achieve normal eyelid function and appearance. However, no comprehensive systematic review has assessed the efficacy and safety of eyelid defect reconstruction. This protocol was developed to conduct a systematic review and meta-analysis to evaluate evidence related to the efficacy and safety of reconstruction. METHODS: We will systematically search the Cochrane Library, PubMed, Web of Science, China National Knowledge Infrastructure, WanFang Database, and Chinese Biomedical Literature Database from their inception to February 2023 for studies on eyelid defect reconstruction. We will identify other potential studies using multiple methods such as manual searching. The outcomes were eyelid function, eyelid morphology, patient satisfaction, recurrence rate, metastasis rate, tumor-related mortality, and adverse events. Two researchers will independently screen titles and abstracts, identify full-text studies for inclusion, extract data, and appraise the risk of bias in the included studies. A meta-analysis will be conducted using Review Manager 5.4 and R software. The certainty of evidence will be appraised by grading of recommendations, assessment, development, and evaluation system. RESULTS: This full-text will adhere to the preferred reporting items for systematic reviews and meta-analyses statement to ensure clarity and completeness of reporting in all phases of the systematic review. DISCUSSION: This study provides evidence of the efficacy and safety of reconstruction methods for sebaceous carcinoma of the eyelid.


Assuntos
Carcinoma Basocelular , Neoplasias Palpebrais , Humanos , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Neoplasias Palpebrais/cirurgia , Pálpebras/cirurgia
9.
Front Plant Sci ; 13: 1104905, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714700

RESUMO

With the advent of multiple omics and Genome-Wide Association Studies (GWAS) technology, genome-scale functional analysis of candidate genes is to be conducted in diverse plant species. Construction of plant binary expression vectors is the prerequisite for gene function analysis. Therefore, it is of significance to develop a set of plant binary expression vectors with highly efficient, inexpensive, and convenient cloning method, and easy-to-use in screening of positive recombinant in Escherichia coli. In this study, we developed a set of plant binary expression vectors, termed pBTR vectors, based on Golden Gate cloning using BsaI restriction site. Foreign DNA fragment of interest (FDI) can be cloned into the destination pBTR by one-step digestion-ligation reaction in a single tube, and even the FDI contains internal BsaI site(s). Markedly, in one digestion-ligation reaction, multiple FDIs (exemplified by cloning four soybean Glyma.02g025400, Glyma.05g201700, Glyma.06g165700, and Glyma.17g095000 genes) can be cloned into the pBTR vector to generate multiple corresponding expression constructs (each expression vector carrying an FDI). In addition, the pBTR vectors carry the visual marker, a brightness monomeric red fluorescent protein mScarlet-I, that can be observed with the unaided eye in screening of positive recombinants without the use of additional reagents/equipment. The reliability of the pBTR vectors was validated in plants by overexpression of AtMyb75/PAP1 in tomato and GUSPlus in soybean roots via Agrobacterium rhizogenes-mediated transformation, promoter activity analysis of AtGCSpro in Arabidopsis via A. tumefaciens-mediated transformation, and protein subcellular localization of the Vitis vinifera VvCEB1opt in tobacco, respectively. These results demonstrated that the pBTR vectors can be used in analysis of gene (over)expression, promoter activity, and protein subcellular localization. These vectors will contribute to speeding up gene function analysis and the process of plant molecular breeding.

10.
Elife ; 102021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33860766

RESUMO

KASH proteins in the outer nuclear membrane comprise the cytoplasmic half of linker of nucleoskeleton and cytoskeleton (LINC) complexes that connect nuclei to the cytoskeleton. Caenorhabditis elegans ANC-1, an ortholog of Nesprin-1/2, contains actin-binding and KASH domains at opposite ends of a long spectrin-like region. Deletion of either the KASH or calponin homology (CH) domains does not completely disrupt nuclear positioning, suggesting neither KASH nor CH domains are essential. Deletions in the spectrin-like region of ANC-1 led to significant defects, but only recapitulated the null phenotype in combination with mutations in the transmembrane (TM) span. In anc-1 mutants, the endoplasmic reticulum ER, mitochondria, and lipid droplets were unanchored, moving throughout the cytoplasm. The data presented here support a cytoplasmic integrity model where ANC-1 localizes to the ER membrane and extends into the cytoplasm to position nuclei, ER, mitochondria, and other organelles in place.


Assuntos
Actinas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Nucleares/metabolismo , Organelas/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação ao Cálcio/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Proteínas dos Microfilamentos/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Movimento , Organelas/genética , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transdução de Sinais , Calponinas
11.
Chem Commun (Camb) ; 57(65): 8055-8058, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34291778

RESUMO

An efficient Pd-catalysed ß-C(sp3)-H arylation of diverse native amides with aryl iodides was developed. This protocol overcomes the necessity of the Thorpe-Ingold effect and features broad substrate scope and good functional group tolerance. The potential application of this protocol is collectively demonstrated by gram-scale synthesis and the synthesis of several bioactive molecules.

12.
Chem Commun (Camb) ; 57(6): 765-768, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33355557

RESUMO

Herein, we report a novel strategy to access CH2F-containing ketones through Pd-catalysed ß-selective methyl C(sp3)-H fluorination. The reaction features high regioselectivity and a broad substrate scope, constituting a modular method for the late-stage transformation of the native methyl (CH3) into the monofluoromethyl (CH2F) group.

13.
J Investig Med ; 68(8): 1349-1356, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33051357

RESUMO

It is reported that lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) is oncogenic in many cancers. This work aimed at probing into its expression and biological functions in retinoblastoma (RB) as well as its regulatory effects on miR-153-3p and hypoxia-inducible factor-1α (HIF-1α). In our study, RB samples in pair were collected, and quantitative real-time PCR (qRT-PCR) was employed for examining the expression levels of KCNQ1OT1, miR-153-3p and HIF-1α. KCNQ1OT1 short hairpin RNAs were transfected into SO-Rb50 and HXO-RB44 cell to inhibit the expression of KCNQ1OT1. The proliferative activity, colony formation ability and apoptosis were examined through cell counting kit-8 assay, colony formation assays, Transwell assay and flow cytometry, respectively. qRT-PCR and western blot analysis were used for analyzing the changes of miR-153-3p and HIF-1α induced by KCNQ1OT1. The regulatory relationships between miR-153-3p and KCNQ1OT1, miR-153-3p and HIF-1α were examined by dual luciferase reporter gene assay and RNA-binding protein immunoprecipitation assay. The results of our study showed that KCNQ1OT1 expression was markedly enhanced in RB tissue samples, and KCNQ1OT1 knockdown had an inhibitory effect on the proliferation, migration, invasion and viability of RB cells. There were two validated binding sties between KCNQ1OT1 and miR-153-3p, and KCNQ1OT1 negatively regulated the expression of miR-153-3p in RB cells. HIF-1α was a target gene of miR-153-3p, and could be positively regulated by KCNQ1OT1. In conclusion, our study indicates that KCNQ1OT1 can increase the malignancy of RB cells via regulating miR-153-3p/HIF-1α axis.


Assuntos
Movimento Celular/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/metabolismo , Retinoblastoma/genética , Retinoblastoma/patologia , Regulação para Cima/genética , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lactente , Invasividade Neoplásica , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-32286977

RESUMO

Image clustering is more challenging than image classification. Without supervised information, current deep learning methods are difficult to be directly applied to image clustering problems. Image clustering needs to deal with three main problems: 1) the curse of dimensionality caused by highdimensional image data; 2) extracting the effective image features; 3) combining feature extraction, dimensionality reduction and clustering. In this paper, we propose a new clustering framework called Deep Embedded Dimensionality Reduction Clustering (DERC) via Probability-Based Triplet Loss, which effectively solves the above issues. To the best of our knowledge, the DERC is the first framework that effectively combines image embedding, dimensionality reduction, and clustering into the image clustering process. We also propose to incorporate a novel probability-based triplet loss measure to retrain the DERC network as a unified framework. By integrating the reconstruction loss and the probability-based triplet loss, we can improve the image clustering accuracy. Extensive experiments show that our proposed methods outperform state-of-the-art methods on many commonly used datasets.

15.
Org Lett ; 22(6): 2396-2402, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32124610

RESUMO

Selective C(sp3)-C(sp2) bond construction is of central interest in chemical synthesis. Despite the success of classic cross-coupling reactions, the cross-dehydrogenative coupling between inert C(sp3)-H and C(sp2)-H bonds represents an attractive alternative toward new C(sp3)-C(sp2) bonds. Herein, we establish a selective inter- and intramolecular C(sp3)-H arylation of alcohols with nondirected arenes that thereby provides a general pathway to access a wide range of ß-arylated alcohols, including tetrahydronaphthalen-2-ols and benzopyran-3-ols, with high to excellent chemo- and regioselectivity.

16.
Org Lett ; 22(21): 8250-8255, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33075228

RESUMO

Herein we report a novel Cu-catalyzed regioselective C2-H alkylation of benzimidazoles with aromatic alkenes. The reaction features exclusive regioselectivity and broad substrate scope in the intermolecular alkylation of benzimidazoles with terminal and internal aromatic alkenes, constituting a modular access toward benzimidazole-containing 1,1-di(hetero)aryl alkanes. The intramolecular C2-H alkylation of benzimidazoles with aromatic alkenes has been achieved in an endo-selective manner. The enantioselective C2 alkylation of benzimidazoles has also been realized with moderate to good stereocontrol.

17.
Nucleus ; 10(1): 73-80, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30888237

RESUMO

LINC complexes (Linker of Nucleoskeleton and Cytoskeleton), consisting of inner nuclear membrane SUN (Sad1, UNC-84) proteins and outer nuclear membrane KASH (Klarsicht, ANC-1, and Syne Homology) proteins, are essential for nuclear positioning, cell migration and chromosome dynamics. To test the in vivo functions of conserved interfaces revealed by crystal structures, Cain et al used a combination of Caenorhabditis elegans genetics, imaging in cultured NIH 3T3 fibroblasts, and Molecular Dynamic simulations, to study SUN-KASH interactions. Conserved aromatic residues at the -7 position of the C-termini of KASH proteins and conserved disulfide bonds in LINC complexes play important roles in force transmission across the nuclear envelope. Other properties of LINC complexes, such as the helices preceding the SUN domain, the longer coiled-coils spanning the perinuclear space and higher-order organization may also function to transmit mechanical forces generated by the cytoskeleton across the nuclear envelope.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Caenorhabditis elegans , Camundongos , Células NIH 3T3
18.
Cells ; 8(10)2019 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-31569501

RESUMO

Neural crest (NC) cells are a temporary population of multipotent stem cells that generate a diverse array of cell types, including craniofacial bone and cartilage, smooth muscle cells, melanocytes, and peripheral neurons and glia during embryonic development. Defective neural crest development can cause severe and common structural birth defects, such as craniofacial anomalies and congenital heart disease. In the early vertebrate embryos, NC cells emerge from the dorsal edge of the neural tube during neurulation and then migrate extensively throughout the anterior-posterior body axis to generate numerous derivatives. Wnt signaling plays essential roles in embryonic development and cancer. This review summarizes current understanding of Wnt signaling in NC cell induction, delamination, migration, multipotency, and fate determination, as well as in NC-derived cancers.


Assuntos
Carcinogênese/metabolismo , Crista Neural/crescimento & desenvolvimento , Via de Sinalização Wnt , Diferenciação Celular , Desenvolvimento Embrionário , Humanos , Crista Neural/metabolismo , Neurogênese
19.
Chem Commun (Camb) ; 55(49): 7049-7052, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31143893

RESUMO

A palladium catalyzed selective C(sp3)-H arylation and acetoxylation of alcohols using a practical bidentate auxiliary were developed. Masked alcohols were selectively arylated at the ß-position with diverse aryl iodides for the first time. Moreover, an efficient and site-selective acetoxylation of various primary methyl, methylene, and benzylic C(sp3)-H bonds was performed by using cheap K2S2O8 as the external oxidant.

20.
Chem Commun (Camb) ; 55(96): 14458-14461, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31728469

RESUMO

A detailed mechanism study on the anion ligand promoted selective C-H bond fluorination is reported. The role of the anion ligand has been clarified by experimental evidence and DFT calculations. Moreover, the nitrate promoted C-F bond reductive elimination enabled a selective C-H bond fluorination of various symmetric and asymmetric azobenzenes to access diverse o-fluoroanilines.

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