light

Light
  • 文章类型: Journal Article
    中华金号,一种传统的藏药用植物,可以在弱光环境中长时间成功茁壮成长。为研究遮荫植物在弱光环境中的适应性进化,通过结合PacBio测序和Hi-C技术,我们产生了染色体规模的基因组组装(〜320Mb)。根据我们的结果,由于细胞内DNA从细胞器基因组转移到核基因组,与光合作用和细胞呼吸相关的基因家族在sinicum基因组中大大扩展和进化。在正选择压力下,捕光复合物II(LHCII)组成蛋白CsLhcb1s的适应性进化导致STN7激酶磷酸化位点苏氨酸残基的扩增,潜在的建立一个关键的基因组基础,以增强C.sinicum在弱光环境中的适应性。通过转录组和代谢组分析,我们确定了大黄烯醇和大黄烯醇苷是中华毛虫的主要类黄酮代谢产物,并预测了它们的合成途径。此外,对选择性剪接(AS)的分析表明,AS事件有助于调节状态转换和类黄酮生物合成。本研究为暴露于弱光条件下的遮荫植物的基因组和这些基因组的适应性进化提供了新的见解;此外,该结果提高了我们目前对chrysospinol和chrysospinoside的生物合成和调节过程的认识。
    Chrysosplenium sinicum, a traditional Tibetan medicinal plant, can successfully thrive in low-light environments for long periods of time. To investigate the adaptive evolution of shade plants in low-light environments, we generated a chromosome-scale genome assembly (~320 Mb) for C. sinicum by combining PacBio sequencing and Hi-C technologies. Based on our results, gene families related to photosynthesis and cell respiration greatly expanded and evolved in C. sinicum genome due to intracellular DNA transfer from organelle genome to nuclear genome. Under positive selective pressure, adaptive evolution of light-harvesting complex II (LHCII) component protein CsLhcb1s resulted in the expansion of threonine residues at the phosphorylation site of STN7 kinase, potentially establishing a crucial genomic foundation for enhancing C. sinicum\'s adaptability in low-light environments. Through transcriptome and metabolome analysis, we identified chrysosplenol and chrysosplenoside as predominant flavonoid metabolites of C. sinicum and predicted their synthesis pathways. In addition, analysis of alternative splicing (AS) revealed that AS events help regulate state transition and flavonoid biosynthesis. The present study provides new insights into the genomes of shade plants exposed to low-light conditions and adaptive evolution of these genomes; in addition, the results improve our current knowledge on the biosynthetic and regulatory processes of chrysosplenol and chrysosplenoside.
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  • 文章类型: Journal Article
    药物污染物对水源的污染对环境和健康具有重大危害,使得开发有效的光催化材料对于它们的去除至关重要。这项研究的重点是新型Ag/CuS/Fe3O4纳米复合材料的合成及其对四环素(TC)和双氯芬酸污染物的光催化效率。纳米复合材料是通过简单且可扩展的沉淀法创建的,将银纳米颗粒(AgNPs)和硫化铜(CuS)整合到磁铁矿框架中。各种分析技术,包括X射线衍射(XRD),扫描电子显微镜(SEM),傅里叶变换红外光谱(FTIR),紫外可见分光光度法(UV-Vis)和能量色散X射线光谱法(EDS),用于表征合成材料的结构和形态特性。通过在可见光下降解四环素和双氯芬酸测试其光催化活性。结果表明,与纯磁铁矿和CuS/Fe控件相比,Ag/CuS/Fe2O纳米复合材料的光催化性能显着提高(在30分钟内TC60ppm的光降解为98%)。提高的光催化效率归因于AgNPs之间的协同相互作用,CuS,和Fe3O4,改善光吸收和电荷分离,从而增加活性氧(ROS)的产生并促进污染物的降解。对于0.02g的催化剂剂量,光降解的速率常数k约为0.1min-1。还测试了光催化剂剂量和TC浓度以及溶液pH值的影响。改性的光催化剂还成功地用于同时光降解TC和双氯芬酸。这项研究强调了Ag/CuS/Fe3O纳米复合材料作为一种有效和可重复使用的光催化剂的潜力,用于消除水中的药物污染物。
    The contamination of water sources by pharmaceutical pollutants presents significant environmental and health hazards, making the development of effective photocatalytic materials crucial for their removal. This research focuses on the synthesis of a novel Ag/CuS/Fe₃O₄ nanocomposite and its photocatalytic efficiency against tetracycline (TC) and diclofenac contaminants. The nanocomposite was created through a straightforward and scalable precipitation method, integrating silver nanoparticles (AgNPs) and copper sulfide (CuS) into a magnetite framework. Various analytical techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR),ultraviolet-visible spectrophotometry (UV-Vis) and energy-dispersive X-ray spectroscopy (EDS), were employed to characterize the structural and morphological properties of the synthesized material. The photocatalytic activity was tested by degrading tetracycline and diclofenac under visible light. Results indicated a marked improvement in the photocatalytic performance of the Ag/CuS/Fe₃O₄ nanocomposite (98%photodegradation of TC 60 ppm in 30 min) compared to both pure magnetite and CuS/Fe₃O₄. The enhanced photocatalytic efficiency is attributed to the synergistic interaction between AgNPs, CuS, and Fe3O4, which improves light absorption and charge separation, thereby increasing the generation of reactive oxygen species (ROS) and promoting the degradation of the pollutants. The rate constant k of photodegradation was about 0.1 min-1 for catalyst dosages 0.02 g. Also the effect of photocatalyst dose and concentration of TC and pH of solution was tested. The modified photocatalyst was also used for simultaneous photodegradation of TC and diclofenac successfully. This study highlights the potential of the Ag/CuS/Fe₃O₄ nanocomposite as an efficient and reusable photocatalyst for eliminating pharmaceutical pollutants from water.
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  • 文章类型: Journal Article
    位于高纬度和多云地区的温室通常质量和数量都很低,尤其是在秋天和冬天。这种低的日光照积分(DLI)降低了生产率,质量,和许多作物的营养价值。这项研究是在SakhiyaRZF1番茄植物上进行的,目的是评估LED灯对由于多云天气而导致每日光照较低的温室中番茄的生长和营养价值的影响。治疗包括三种模式的LED生长灯:顶部照明,顶篷内照明,并结合顶部和顶篷内照明。结果表明,尽管顶部和冠层内光照的组合达到了番茄产量的最大增加,但与整个生产年度没有补充照明相比,仅暴露于冠层内LED照明的番茄果实产量增加(28.46%)优于仅暴露于顶级LED照明(12.12%)。冠内暴露表现出番茄番茄红素的最高增加(31.3%),与对照相比,顶部和冠层内照明显示维生素C含量的最高增加(123.4%)。LED光处理对负责代谢周期的基因的表达也有非常积极的影响,包括Psy1、LCY-β、和VTC2基因,随着番茄果实产量的增加而存在共线性。
    Greenhouses located at high latitudes and in cloudy areas often experience a low quality and quantity of light, especially during autumn and winter. This low daily light integral (DLI) reduces production rate, quality, and nutritional value of many crops. This study was conducted on Sakhiya RZ F1 tomato plants to evaluate the impact of LED lights on the growth and nutritional value of tomatoes in a greenhouse with low daily light due to cloudy weather. The treatments included LED growth lights in three modes: top lighting, intra-canopy lighting, and combined top and intra-canopy lighting. The results showed that although the combined top and intra-canopy lighting reached the maximum increase in tomato yield, exposure to intra-canopy LED lighting alone outperformed in tomato fruit yield increase (28.46%) than exposure to top LED lighting alone (12.12%) when compared to no supplemental lighting during the entire production year. Intra-canopy exposure demonstrated the highest increase in tomato lycopene (31.3%), while top and intra-canopy lighting exhibited the highest increase in vitamin C content (123.4%) compared to the control. The LED light treatment also had a very positive effect on the expression of genes responsible for metabolic cycles, including Psy1, LCY-β, and VTC2 genes, which had collinearity with the increase in tomato fruit production.
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  • 文章类型: Journal Article
    真核蛋白质编码基因的转录产生未成熟的mRNAs,这些mRNAs会经历一系列加工事件,包括封顶,拼接,乳沟,和聚腺苷酸化(CPA),和碱基的化学修饰。选择性聚腺苷酸化(APA)极大地促进了细胞中的mRNA多样性。通过确定3'个未翻译区域的长度,APA产生具有不同调控元件的转录本,如miRNA和RBP结合位点,会影响mRNA的稳定性,营业额,和翻译。在模型植物拟南芥中,APA参与种子休眠和开花的控制。鉴于APA在植物中的生理重要性,我们决定研究光/暗条件的影响,并将潜在机制与阐明的可变剪接(AS)机制进行比较.我们发现光控制大约30%的拟南芥基因中的APA。类似于AS,光对APA的影响需要功能性叶绿体,在植物色素和隐色素光感受器途径的突变体中不受影响,只有当与光合组织的交流不中断时,才能在根中观察到。此外,线粒体和TOR激酶活性是光作用所必需的。然而,与AS不同,似乎不涉及与转录延伸的偶联,因为TFIIS转录物延伸因子的突变体中既没有消除光依赖性APA调节,也没有受到组蛋白去乙酰化酶抑制引起的染色质松弛的普遍影响。相反,监管似乎与构成注册会计师因素的丰度变化相关,也由叶绿体介导。
    Transcription of eukaryotic protein-coding genes generates immature mRNAs that are subjected to a series of processing events, including capping, splicing, cleavage, and polyadenylation (CPA), and chemical modifications of bases. Alternative polyadenylation (APA) greatly contributes to mRNA diversity in the cell. By determining the length of the 3\' untranslated region, APA generates transcripts with different regulatory elements, such as miRNA and RBP binding sites, which can influence mRNA stability, turnover, and translation. In the model plant Arabidopsis thaliana, APA is involved in the control of seed dormancy and flowering. In view of the physiological importance of APA in plants, we decided to investigate the effects of light/dark conditions and compare the underlying mechanisms to those elucidated for alternative splicing (AS). We found that light controls APA in approximately 30% of Arabidopsis genes. Similar to AS, the effect of light on APA requires functional chloroplasts, is not affected in mutants of the phytochrome and cryptochrome photoreceptor pathways, and is observed in roots only when the communication with the photosynthetic tissues is not interrupted. Furthermore, mitochondrial and TOR kinase activities are necessary for the effect of light. However, unlike AS, coupling with transcriptional elongation does not seem to be involved since light-dependent APA regulation is neither abolished in mutants of the TFIIS transcript elongation factor nor universally affected by chromatin relaxation caused by histone deacetylase inhibition. Instead, regulation seems to correlate with changes in the abundance of constitutive CPA factors, also mediated by the chloroplast.
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  • 文章类型: Journal Article
    枯萎是影响茶叶品质的第一个也是关键的过程,光质量是一个关键的调节因素。然而,枯萎光质(WLQ)对茶叶香气和挥发性代谢产物(VMs)转化和形成途径的影响尚不清楚。在本研究中,建立了四个WLQ来研究它们对茶香气和VM的影响。结果表明,蓝光和红光降低了草香气,改善了茶的花香和果香。基于GC-MS/MS,检测到83个VM。通过VIP,显著差异,和OAV分析,筛选了13个关键差异VM,以表征WLQ对茶叶香气的差异影响。进一步的进化和代谢途径分析表明,糖苷代谢是通过WLQ调节茶香的关键途径。蓝光枯萎显着增强糖苷水解和氨基酸脱氨,这有利于丰富花香和果味的虚拟机,如香叶醇,柠檬醛,水杨酸甲酯,2-甲基-丁醛,和苯乙醛,以及草地虚拟机的改造,例如octanal,萘,和顺式-3-己烯基异戊酸酯,从而形成茶叶花香和果香。研究结果为优质茶叶的针对性加工提供了理论依据和技术支持。
    Withering is the first and key process that influences tea quality, with light quality being a key regulatory factor. However, effects of withering light quality (WLQ) on transformation and formation pathways of tea aroma and volatile metabolites (VMs) remain unclear. In the present study, four WLQs were set up to investigate their effects on tea aroma and VMs. The results showed that blue and red light reduced the grassy aroma and improved the floral and fruity aroma of tea. Based on GC-MS/MS, 83 VMs were detected. Through VIP, significant differences, and OAV analysis, 13 key differential VMs were screened to characterize the differential impacts of WLQ on tea aroma. Further analysis of the evolution and metabolic pathways revealed that glycoside metabolism was the key pathway regulating tea aroma through WLQ. Blue light withering significantly enhanced glycosides hydrolysis and amino acids deamination, which was beneficial for the enrichment of floral and fruity VMs, such as geraniol, citral, methyl salicylate, 2-methyl-butanal, and benzeneacetaldehyde, as well as the transformation of grassy VMs, such as octanal, naphthalene, and cis-3-hexenyl isovalerate, resulting in the formation of tea floral and fruity aroma. The results provide theoretical basis and technical support for the targeted processing of high-quality tea.
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  • 文章类型: Journal Article
    人参的地理来源显著影响其营养价值和化学成分,进而影响其市场价格。分析这些差异的传统方法通常很耗时,并且需要大量的试剂,使他们效率低下。因此,高光谱成像(HSI)结合X射线技术用于人参产地的快速和无损可追溯性。最初,通过采用组合的孤立森林算法和密度峰值聚类(DPC)算法,可以有效地拒绝离群样本。随后,利用高光谱数据构建随机森林(RF)和支持向量机(SVM)分类模型。通过应用72种预处理方法及其组合,进一步优化了这些模型。此外,为了提高模型的性能,采用了四种变量筛选算法:SelectKBest,遗传算法(GA),最小绝对收缩和选择运算符(LASSO),和排列特征重要性(PFI)。优化后的模型,利用二阶导数,自动缩放,排列特征重要性,和支持向量机(2ndDer-AS-PFI-SVM),实现了93.4%的预测精度,在独立预测集上,Kappa值为0.876,Brier评分为0.030,F1评分为0.932,AUC为0.994。此外,从彩色和X射线图像中提取的图像数据(包括颜色信息和纹理信息)用于构建分类模型并评估其性能。其中,利用X射线图像的纹理信息构建的SVM模型表现最好,在验证集上实现了63.0%的预测精度,Brier评分为0.181,F1评分为0.518,AUC为0.553。通过基于Stacking策略实现中层融合和高层数据融合,发现采用高光谱光谱信息和X射线图像纹理信息的高级融合的模型明显优于仅使用高光谱光谱信息的模型。这种先进的模型达到了95.2%的预测精度,在独立预测集上,Kappa值为0.912,Brier评分为0.027,F1评分为0.952,AUC为0.997。总之,本研究不仅为人参产地的快速、无损溯源提供了一条新的技术路径,同时也展示了HSI和X射线技术在医药和食品可追溯性领域的联合应用的巨大潜力。
    The geographical origin of Panax ginseng significantly influences its nutritional value and chemical composition, which in turn affects its market price. Traditional methods for analyzing these differences are often time-consuming and require substantial quantities of reagents, rendering them inefficient. Therefore, hyperspectral imaging (HSI) in conjunction with X-ray technology were used for the swift and non-destructive traceability of Panax ginseng origin. Initially, outlier samples were effectively rejected by employing a combined isolated forest algorithm and density peak clustering (DPC) algorithm. Subsequently, random forest (RF) and support vector machine (SVM) classification models were constructed using hyperspectral spectral data. These models were further optimized through the application of 72 preprocessing methods and their combinations. Additionally, to enhance the model\'s performance, four variable screening algorithms were employed: SelectKBest, genetic algorithm (GA), least absolute shrinkage and selection operator (LASSO), and permutation feature importance (PFI). The optimized model, utilizing second derivative, auto scaling, permutation feature importance, and support vector machine (2nd Der-AS-PFI-SVM), achieved a prediction accuracy of 93.4 %, a Kappa value of 0.876, a Brier score of 0.030, an F1 score of 0.932, and an AUC of 0.994 on an independent prediction set. Moreover, the image data (including color information and texture information) extracted from color and X-ray images were used to construct classification models and evaluate their performance. Among them, the SVM model constructed using texture information from X -ray images performed the best, and it achieved a prediction accuracy of 63.0 % on the validation set, with a Brier score of 0.181, an F1 score of 0.518, and an AUC of 0.553. By implementing mid-level fusion and high-level data fusion based on the Stacking strategy, it was found that the model employing a high-level fusion of hyperspectral spectral information and X-ray images texture information significantly outperformed the model using only hyperspectral spectral information. This advanced model attained a prediction accuracy of 95.2 %, a Kappa value of 0.912, a Brier score of 0.027, an F1 score of 0.952, and an AUC of 0.997 on the independent prediction set. In summary, this study not only provides a novel technical path for fast and non-destructive traceability of Panax ginseng origin, but also demonstrates the great potential of the combined application of HSI and X-ray technology in the field of traceability of both medicinal and food products.
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  • 文章类型: Journal Article
    这项原始工作研究了受意大利青霉感染的南丰橘子(NF)和赣南脐橙(GN)的黄酮中的光学特性和基于蒙特卡罗(MC)的光传播模拟。在储存过程中,在感染的NF和GN中都观察到了约482nm处的吸收系数(μa)的增加和约675nm处的减小。表明类胡萝卜素的积累和叶绿素的损失。特别是,NF中的μa变化比GN更强烈,但是在采后感染时检测到降低的散射系数(μs')的有限差异。此外,光传播的MC模拟表明,NF中482nm处的光子包重量和穿透深度比GN中的减少更多。而在926nm的相对较低的吸收波长下几乎没有变化。在感染期间,NF和GN在482nm处的模拟吸收能量比在675nm处的变化更大。从而可以更好地检测柑橘病害。此外,PLS-DA模型可以区分健康和受感染的柑橘,NF的准确率为95.24%,GN的准确率为98.67%,分别。因此,这些结果可以为提高建模预测的鲁棒性和准确性提供理论基础。
    This original work investigated the optical properties and Monte-Carlo (MC) based simulation of light propagation in the flavedo of Nanfeng tangerine (NF) and Gannan navel orange (GN) infected by Penicillium italicum. The increase of absorption coefficient (μa) at around 482 nm and the decrease at around 675 nm were both observed in infected NF and GN during storage, indicating the accumulation of carotenoids and loss of chlorophyll. Particularly, the μa in NF varied more intensively than GN, but the limited differences of reduced scattering coefficient (μs\') were detected while postharvest infection. Besides, MC simulation of light propagation indicated that the photon packets weight and penetration depth at 482 nm in NF were reduced more than in GN flavedo, while there were almost no changes at the relatively low absorption wavelength of 926 nm. The simulated absorption energy at 482 nm in NF and GN presented more changes than those at 675 nm during infection, thus could provide better detection of citrus diseases. Furthermore, PLS-DA models can discriminate healthy and infected citrus, with the accuracy of 95.24 % for NF and 98.67 % for GN, respectively. Consequently, these results can provide theoretical fundamentals to improve modelling prediction robustness and accuracy.
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  • 文章类型: Journal Article
    众所周知,夜光会产生各种各样的行为结果,包括促进焦虑,抑郁症,多动症,不正常的社交能力,学习和记忆缺陷。不幸的是,我们都生活在一个24小时的社会中,人们在夜班工作中暴露于夜间照明或光污染-需要全天候的紧急服务-以及建筑物和路灯,使夜间光照几乎不可避免。此外,夜间屏幕时间(电视和智能设备)的增加也导致睡眠和行为障碍恶化。使这些因素更加复杂的是,与年幼的儿童和成人相比,青少年倾向于“夜猫子”,并且更喜欢晚上的时间型。所以这些青少年将有更高的可能性被暴露在晚上的光。更糟糕的是,早上8点或更早的高中开学时间普遍存在——这是过早的开学时间的组合,在夜间曝光,偏爱晚上的时间型是减少和减少睡眠的秘诀,这可能导致该人群对行为问题的易感性增加。因此,这个迷你评论将显示,使用人类和啮齿动物模型研究,夜光如何影响行为结果和应激反应,将光信号和昼夜节律定时系统连接到下丘脑-垂体肾上腺轴。此外,这项审查还将表明,青少年更有可能表现出异常的行为,以响应晚上的光,由于在这段时间内的发育和激素调节的变化,以及讨论有助于减轻这些负面影响的潜在干预措施。
    Light-at-night is known to produce a wide variety of behavioral outcomes including promoting anxiety, depression, hyperactivity, abnormal sociability, and learning and memory deficits. Unfortunately, we all live in a 24-h society where people are exposed to light-at-night or light pollution through night-shift work - the need for all-hours emergency services - as well as building and street-lights, making light-at-night exposure practically unavoidable. Additionally, the increase in screentime (tvs and smart devices) during the night also contributes to poorer sleep and behavioral impairments. Compounding these factors is the fact that adolescents tend to be \"night owls\" and prefer an evening chronotype compared to younger children and adults, so these teenagers will have a higher likelihood of being exposed to light-at-night. Making matters worse is the prevalence of high-school start times of 8 am or earlier - a combination of too early school start times, light exposure during the night, and preference for evening chronotypes is a recipe for reduced and poorer sleep, which can contribute to increased susceptibility for behavioral issues for this population. As such, this mini-review will show, using both human and rodent model studies, how light-at-night affects behavioral outcomes and stress responses, connecting photic signaling and the circadian timing system to the hypothalamic-pituitary adrenal axis. Additionally, this review will also demonstrate that adolescents are more likely to exhibit abnormal behavior in response to light-at-night due to changes in development and hormone regulation during this time period, as well as discuss potential interventions that can help mitigate these negative effects.
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  • 文章类型: Journal Article
    瞳孔光反射(PLR)适应到达视网膜的光量,保护它并改善图像形成。已经在脊椎动物中描述了两种PLR机制。首先,前盖接受视网膜输入并投射到Edinger-Westphal核(EWN),通过动眼神经(nIII)靶向睫状神经节。节后纤维进入眼球,行进到虹膜括约肌.此外,一些脊椎动物表现出由表达黑视蛋白诱导肌肉收缩的括约肌细胞介导的虹膜固有PLR机制。考虑到七叶鱼视觉系统的高度保护,我们研究了PLR的潜在机制,揭示了它们的进化起源。最近,由黑视蛋白介导的PLR在七翅目中得到证实,暗示是大脑介导的。值得注意的是,我们发现PLR是由直接的retino-iridal胆碱能投射介导的.这种视网膜介导的PLR与虹膜内在机制协同作用,和其他脊椎动物一样,由黑视素介导,并对肌纤维之间的缝隙连接有贡献。相比之下,我们表明七翅目缺乏脑介导的PLR。我们的结果表明,在早期脊椎动物进化中存在两种眼睛固有的PLR机制,而脑介导的PLR具有更近的起源。
    The pupillary light reflex (PLR) adapts the amount of light reaching the retina, protecting it and improving image formation. Two PLR mechanisms have been described in vertebrates. First, the pretectum receives retinal inputs and projects to the Edinger-Westphal nucleus (EWN), which targets the ciliary ganglion through the oculomotor nerve (nIII). Postganglionic fibers enter the eye-globe, traveling to the iris sphincter muscle. Additionally, some vertebrates exhibit an iris-intrinsic PLR mechanism mediated by sphincter muscle cells that express melanopsin inducing muscle contraction. Given the high degree of conservation of the lamprey visual system, we investigated the mechanisms underlying the PLR to shed light onto their evolutionary origins. Recently, a PLR mediated by melanopsin was demonstrated in lampreys, suggested to be brain mediated. Remarkably, we found that PLR is instead mediated by direct retino-iridal cholinergic projections. This retina-mediated PLR acts synergistically with an iris-intrinsic mechanism that, as in other vertebrates, is mediated by melanopsin and has contribution of gap junctions between muscle fibers. In contrast, we show that lampreys lack the brain-mediated PLR. Our results suggest that two eye-intrinsic PLR mechanisms were present in early vertebrate evolution, whereas the brain-mediated PLR has a more recent origin.
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  • 文章类型: Journal Article
    光氧电压感应域(LOV)超家族,在酶和信号转导蛋白中发现,在将光信号转换为结构信号中起着至关重要的作用,介导各种生物学机制。虽然时间分辨光谱研究揭示了LOV域发色团电子结构的动力学,了解蛋白质部分的结构变化,特别是关于光诱导的二聚化,仍然具有挑战性。这里,我们利用时间分辨X射线液相成像来捕获AvenasativaLOV2的光诱导二聚化。我们的分析揭示了在微秒时间范围内A\'α和Jα螺旋展开后的毫秒内发生二聚化。值得注意的是,我们的发现表明,β-支架之间的蛋白质-蛋白质相互作用(PPI),由螺旋展开介导,在二聚化中起关键作用。在这项工作中,我们提供了对LOV2蛋白在A\'α和Jα螺旋结构变化后的二聚化的结构见解,以及对PPI驱动的蛋白质-蛋白质缔合过程的机械见解。
    The Light-oxygen-voltage-sensing domain (LOV) superfamily, found in enzymes and signal transduction proteins, plays a crucial role in converting light signals into structural signals, mediating various biological mechanisms. While time-resolved spectroscopic studies have revealed the dynamics of the LOV-domain chromophore\'s electronic structures, understanding the structural changes in the protein moiety, particularly regarding light-induced dimerization, remains challenging. Here, we utilize time-resolved X-ray liquidography to capture the light-induced dimerization of Avena sativa LOV2. Our analysis unveils that dimerization occurs within milliseconds after the unfolding of the A\'α and Jα helices in the microsecond time range. Notably, our findings suggest that protein-protein interactions (PPIs) among the β-scaffolds, mediated by helix unfolding, play a key role in dimerization. In this work, we offer structural insights into the dimerization of LOV2 proteins following structural changes in the A\'α and Jα helices, as well as mechanistic insights into the protein-protein association process driven by PPIs.
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