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Ma Jiachi Liang Wanqing Qiang Yaosheng Li Lei Du Jun Pan Chengwu Chen Bangling Zhang Chensong Chen Yuzhong Wang Qingkang 《Cell communication and signaling : CCS》2021,19(1):1-12
Wnt signaling plays key roles in cellular and physiological processes, including cell proliferation, differentiation and migration during development and tissue homeostasis in adults. This pathway can be defined as Wnt/β-catenin-dependent or β-catenin-independent or “non-canonical”, both signaling are involved in neurite and synapse development/maintenance. Porcupine (PORCN), an acylase that o-acylates Wnt ligands, a major modification in secretion and interaction with its receptors. We use Wnt-C59, a specific PORCN inhibitor, to block the secretion of endogenous Wnts in embryonic hippocampal neurons (DIV 4). Under these conditions, the activity of exogenous Wnt ligands on the complexity of the dendritic tree and axonal polarity were evaluated Cultured primary embryonic hippocampal neurons obtained from Sprague–Dawley rat fetuses (E18), were cultured until day in vitro (DIV) 4 (according to Banker´s protocol) and treated with Wnt-C59 for 24 h, Wnt ligands were added to the cultures on DIV 3 for 24 h. Dendritic arbors and neurites were analysis by fluorescence microscopy. Transfection with Lipofectamine 2000 on DIV 2 of plasmid expressing eGFP and KIF5-Cherry was carried out to evaluate neuronal polarity. Immunostaining was performed with MAP1B and Tau protein. Immunoblot analysis was carried out with Wnt3a, β-catenin and GSK-3β (p-Ser9). Quantitative analysis of dendrite morphology was carried out with ImageJ (NIH) software with Neuron J Plugin. We report, here, that Wnt-C59 treatment changed the morphology of the dendritic arbors and neurites of embryonic hippocampal neurons, with decreases β-catenin and Wnt3a and an apparent increase in GSK-3β (p-Ser9) levels. No effect was observed on axonal polarity. In sister cultures, addition of exogenous Wnt3a, 5a and 7a ligands rescued the changes in neuronal morphology. Wnt3a restored the length of neurites to near that of the control, but Wnt7a increased the neurite length beyond that of the control. Wnt5a also restored the length of neurites relative to Wnt concentrations. Results indicated that Wnt ligands, added exogenously, restored dendritic arbor complexity in embryonic hippocampal neurons, previously treated with a high affinity specific Porcupine inhibitor. We proposed that PORCN is an emerging molecular target of interest in the search for preclinical options to study and treat Wnt-related diseases. 相似文献
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Ning Xie Yunfan Bai Lu Qiao Yuru Bai Jian Wu Yan Li Mingzuo Jiang Bing Xu Zhen Ni Ting Yuan Yongquan Shi Kaichun Wu Feng Xu Jinhai Wang Lei Dong Na Liu 《Journal of cellular and molecular medicine》2021,25(8):4014-4027
The ADP-ribosylation factor-like proteins (ARLs) have been proved to regulate the malignant phenotypes of several cancers. However, the exact role of ARLs in gastric cancer (GC) remains elusive. In this study, we systematically investigate the expression status, interactive relations, potential pathways, genetic variations and clinical values of ARLs in GC. We find that ARLs are significantly dysregulated in GC and involved in various cancer-related pathways. Subsequently, machine learning models identify ARL4C as one of the two most significant clinical indicators among ARLs for GC. Furthermore, ARL4C silencing remarkably inhibits the growth and metastasis of GC cells both in vitro and in vivo. Moreover, enrichment analysis indicates that ARL4C is highly correlated with TGF-β1 signalling. Correspondingly, TGF-β1 treatment dramatically increases ARL4C expression and ARL4C knockdown inhibits the phosphorylation level of Smads, downstream factors of TGF-β1. Meanwhile, the coexpression of ARL4C and TGF-β1 worsens the prognosis of GC patients. Our work comprehensively demonstrates the crucial role of ARLs in the carcinogenesis of GC and the specific mechanisms underlying the GC-promoting effects of TGF-β1. More importantly, we uncover the great promise of ARL4C-targeted therapy in improving the efficacy of TGF-β1 inhibitors for GC patients. 相似文献
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Gao Kai Liu Meiyou Li Yuan Wang Lei Zhao Chao Zhao Xian Zhao Jinyi Ding Yi Tang Haifeng Jia Yanyan Wang Jingwen Wen Aidong 《Journal of molecular histology》2021,52(3):449-459
Journal of Molecular Histology - Currently, the excessive activation of N-methyl-D-aspartate receptors (NMDARs) is considered to be a crucial mechanism of brain injury. Lycium barbarum A (LyA) is a... 相似文献
126.
Li Zhenzi Liu Pan Yuan Yanan Liang Xiaoxiao Lei Jun Zhu Xiaobin Zhang Zuoqi Cai Lin 《Biomechanics and modeling in mechanobiology》2021,20(5):2013-2030
Biomechanics and Modeling in Mechanobiology - Osteoporosis (OP), a skeletal disease making bone mechanically deteriorate and easily fracture, is a global public health issue due to its high... 相似文献
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叶绿醌是由1个萘醌环和1个半不饱和植基侧链组成的一类光系统Ⅰ(photosystem Ⅰ,PSⅠ)特有的辅因子。目前,在蓝藻中对其生物合成途径的研究主要集中在萘醌环的形成方面,而对其植基侧链的合成尚缺乏相关报道。本研究通过与近期在拟南芥中发现的1种催化植基单磷酸形成植基二磷酸的激酶(VTE6)进行同源序列比对,在集胞藻 PCC 6803中发现1个与之高度同源的蛋白质Sll0875。研究发现,在Sll0875缺失突变体中,叶绿醌和生育酚的含量缺失,叶绿素的含量降低(P<0.05),且该突变体在无葡萄糖培养基中生长迟缓。进一步利用叶绿素荧光、P700氧化还原动力学、77K低温荧光光谱和免疫印迹分析等方法分析了该蛋白质的缺失对PSⅠ功能的影响。研究表明,在突变体Δsll0875中, PSⅠ活性下降,PSⅠ亚基含量与野生型相比显著降低(P<0.01)。这一结果表明,叶绿醌的缺失影响了PSⅠ复合物的累积,导致PSⅠ功能受损,从而影响了蓝藻正常的生长和发育。本研究在蓝藻中证实植醇磷酸化途径对叶绿醌合成的重要性,为进一步研究蓝藻中叶绿醌在PSⅠ复合物的合成、组装和稳定等过程中的作用奠定基础。 相似文献
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Zhaolei Qiu Feng Xu Zhenjie Wang Peng Yang Zhang Bu Feng Cheng Hai Jiang Lei Li Fulong Zhang 《Biochemistry and Biophysics Reports》2021
JAK/STAT plays an important role in cytokine signal transduction and it is potentially involved in the proinflammatory response during the early phase of severe acute pancreatitis (SAP). However, whether JAK2 activity is upregulated and whether JAK2 inhibition plays a role in the maintenance of pancreatic homeostasis during SAP is incompletely understood. Here we show that JAK2/STAT3 activity is highly elevated in SAP and blockade of JAK2 by AG-490 protects against SAP-induced pancreatic inflammation and injury. Gene expression and ELISA studies showed that JAK2 inhibition altered the cytokine profiles in both the circulation and pancreases. Further analysis revealed that JAK2 inhibition restored the level of cytokines critical for macrophage polarization towards M2 macrophage. Our findings suggest that pharmacological targeting at JAK2/STAT signalling may be an effective choice of therapeutic interventions against SAP. 相似文献
130.
[目的]通过分析中华蜜蜂Apis cerana cerana气味受体基因AcerOR58编码蛋白的理化性质、结构特征,明确AcerOR58时空表达特性,为该基因后续的功能研究奠定基础.[方法]利用多种生物信息学软件预测分析AcerOR58序列及其编码蛋白的结构特性,采用邻接法构建系统进化树.利用实时荧光定量PCR技术分析AcerOR58在不同发育阶段工蜂触角及采集蜂不同组织的表达差异.[结果]AcerOR58基因的开放阅读框(ORF)长1 230 bp,编码409个氨基酸,成熟蛋白分子量为47.147 ku,理论等电点8.46,无信号肽,含有6个跨膜结构且N端位于胞内,31个潜在的磷酸化位点,在第80-405位氨基酸之间存在一个昆虫气味受体家族7tm_6 superfamily保守结构域.AcerOR58与西方蜜蜂Apis mellifera的AmelOR58亲缘关系最近,核苷酸序列一致性高达96.67%,氨基酸序列一致性高达97.31%.AcerOR58在采集蜂(15-25日龄)阶段的表达量较高,且在触角中的表达量极显著高于其他组织(P<0.01).[结论]AcerOR58具有昆虫气味受体的结构特征,该基因特异性高表达于中华蜜蜂采集蜂触角中,推测其功能与识别外界蜜粉源的花香气味物质有关. 相似文献