kinetic analysis

动力学分析
  • 文章类型: Journal Article
    超声波技术具有显著的脱气效果,可以提高质子交换膜电解水的制氢效率。然而,其对氢气气泡的影响机制有待进一步研究。在这项工作中,在质子交换膜电解槽中,通过在静态和流动动力学下应用超声放大技术,进行了动力学分析,以研究氢气的产生原理和氢气气泡析出的动力学行为。通过成像表征了在超声下电解质水溶液的静态和流动动力学中氢气泡的演变。结果表明,与静止状态相比,流动状态的电解质水溶液减小了氢气气泡的尺寸,提高了分离速度,这促进了氢气气泡的形成过程,并且认为超声波在流动状态下对电解质水溶液温度的热效应与静止状态相比很小,可以忽略。超声对氢气气泡演化的不同阶段有不同的影响。在成核阶段,超声空化效应增加了高反应性自由基,如·OH,H•,等。,超声波的机械振动效应增加了成核位点,密度更大,分布更均匀。在成长阶段,超声空化效应和机械振动效应促进了水分子氢键的断裂,改善了传质,促进氢气泡的生长,正负超声的波动能量随着振动速度的加快促进氢气气泡的生长。在分离阶段,氢气泡的半径受超声波的影响。氢气泡的半径随着正负超声压力的变化而变化,在负超声压力下氢气泡的半径增加,正超声压力降低,氢气泡半径的变化效应有利于氢气泡的分离。在聚合阶段,超声导致细气泡流的聚合增加。超声有助于质子交换膜水电解在实际运行中的制氢效果。
    Ultrasonic technology has a significant degassing effect and can increase the efficiency of hydrogen production in the proton exchange membrane electrolysis of water. However, further research is needed to understand its influence mechanism on hydrogen bubbles. In this work, a kinetic analysis is performed to investigate the principle of hydrogen production and the kinetic behaviour of hydrogen bubble evolution by applying the ultrasonic amplification technique under static and flow dynamics in the proton exchange membrane electrolysis cell. The evolution of hydrogen bubbles in the static and in the flow dynamic of the aqueous electrolyte solution under ultrasound was characterised by imaging. The results show that the aqueous electrolyte solution in the flow state reduces the size of hydrogen bubbles and increases the detachment speed compared to the static state, which promotes the process of hydrogen bubble evolution, and that the thermal effect of ultrasound on the temperature of the aqueous electrolyte solution in the flow state is very small compared to the static state and can be ignored. Ultrasound has different effects on the different stages of hydrogen bubble evolution. In the nucleation stage, the ultrasonic cavitation effect increases the highly reactive radicals such as •OH, H•, etc., and the mechanical vibration effect of ultrasound increases the nucleation sites, which are denser and more evenly distributed. In the growth phase, the ultrasonic cavitation effect and the mechanical vibration effect promote the breaking of hydrogen bonds of water molecules and improve mass transport, which promotes the growth of hydrogen bubbles, and the fluctuating energy of positive and negative ultrasound promotes the growth of hydrogen bubbles with the vibration speed. In the detachment phase, the radius of the hydrogen bubbles is influenced by the ultrasound. The radius of the hydrogen bubbles changes with the positive and negative ultrasonic pressure, the radius of the hydrogen bubbles at negative ultrasonic pressure increases, the positive ultrasonic pressure decreases, the changing effect of the radius of the hydrogen bubbles favours the detachment of the hydrogen bubbles. In the polymerisation phase, the ultrasound leads to increased polymerisation of the fine bubble streams. Ultrasound contributes to the hydrogen production effect of proton exchange membrane water electrolysis in actual operation.
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  • 文章类型: Journal Article
    SLC25线粒体载体家族的成员将胞质和线粒体代谢联系起来,并通过跨线粒体内膜运输化合物来支持细胞维持和生长。它们的单体或二聚体状态和动力学机制一直是一个长期争论的问题。一些人认为它们作为同二聚体和运输底物存在,具有顺序的动力学机制,形成三元复合物,其中两个交换的底物同时结合。一些研究,相比之下,提供的证据表明,线粒体ADP/ATP载体(SLC25A4)作为一个单体,有一个单一的底物结合位点,并具有乒乓动力学机制,在导出ATP之前导入ADP。在这里,我们重新分析了人类线粒体柠檬酸盐载体(SLC25A1)的寡聚状态和动力学特性,二羧酸载体(SLC25A10),酮戊二酸载体(SLC25A11),和天冬氨酸/谷氨酸载体(SLC25A13),以前报道的所有二聚体都具有顺序的动力学机制。我们证明它们是单体,除了二聚体SLC25A13之外,并以乒乓动力学机制运行,其中底物导入和导出步骤连续发生。这些观察结果与共同的运输机制是一致的,基于功能单体,其中单个中心底物结合位点是交替可接近的。
    Members of the SLC25 mitochondrial carrier family link cytosolic and mitochondrial metabolism and support cellular maintenance and growth by transporting compounds across the mitochondrial inner membrane. Their monomeric or dimeric state and kinetic mechanism have been a matter of long-standing debate. It is believed by some that they exist as homodimers and transport substrates with a sequential kinetic mechanism, forming a ternary complex where both exchanged substrates are bound simultaneously. Some studies, in contrast, have provided evidence indicating that the mitochondrial ADP/ATP carrier (SLC25A4) functions as a monomer, has a single substrate binding site, and operates with a ping-pong kinetic mechanism, whereby ADP is imported before ATP is exported. Here we reanalyze the oligomeric state and kinetic properties of the human mitochondrial citrate carrier (SLC25A1), dicarboxylate carrier (SLC25A10), oxoglutarate carrier (SLC25A11), and aspartate/glutamate carrier (SLC25A13), all previously reported to be dimers with a sequential kinetic mechanism. We demonstrate that they are monomers, except for dimeric SLC25A13, and operate with a ping-pong kinetic mechanism in which the substrate import and export steps occur consecutively. These observations are consistent with a common transport mechanism, based on a functional monomer, in which a single central substrate-binding site is alternately accessible.
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  • 文章类型: Journal Article
    在这项研究中,我们报道了一种新型高灵敏度基于强度的表面等离子体共振成像(SPRi)生物传感器的成功开发及其在检测分子相互作用中的应用。通过优化激发波长并采用波分复用(WDM)算法,该系统可以根据样品的初始折射率确定最佳激发波长,而无需调整入射角。实验结果表明,该系统的折射率分辨率达到1.77×10-6RIU。此外,它可以获得初始折射率在1.333至1.370RIU范围内的样品的最佳激发波长,并精确监测0.0037RIU范围内的变化,而无需调整入射角。此外,我们的新SPRi技术实现了高通量生物分子结合过程的实时检测,能够分析动力学参数。这项研究有望促进更精确的SPRi分子相互作用分析技术的发展。
    In this study, we report the successful development of a novel high-sensitivity intensity-based Surface Plasmon Resonance imaging (SPRi) biosensor and its application for detecting molecular interactions. By optimizing the excitation wavelength and employing a wavelength division multiplexing (WDM) algorithm, the system can determine the optimal excitation wavelength based on the initial refractive index of the sample without adjusting the incidence angle. The experimental results demonstrate that the refractive index resolution of the system reaches 1.77×10-6 RIU. Moreover, it can obtain the optimal excitation wavelength for samples with an initial refractive index in the range of 1.333 to 1.370 RIU and accurately monitor variations within the range of 0.0037 RIU without adjusting the incidence angle. Additionally, our new SPRi technique realized real-time detection of high-throughput biomolecular binding processes, enabling analysis of kinetic parameters. This research is expected to advance the development of more accurate SPRi technologies for molecular interaction analysis.
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  • 文章类型: Journal Article
    本文研究了褐煤(L)和干松木(TPW)在不同掺烧比下混合燃烧的燃烧特性和污染物排放规律。在800℃的固定床反应系统中进行了等温燃烧实验,使用烟气分析仪测量污染物排放浓度。利用扫描电镜(SEM)和BET(氮气吸附)实验,研究发现,烘焙松木(TPW)具有更大的比表面积和更发达的孔隙结构,这可以促进样品更完全的燃烧。非等温热重分析结果表明,随着TPW掺和比的增加,整个燃烧过程都在推进,和点火温度,最高峰值温度,和燃尽温度均呈下降趋势。通过Flynn-Wall-Ozawa(FWO)和Kissinger-Akahira-Sunose(KAS)动力学方程计算了混合气体燃烧反应过程的动力学方程。结果表明,TPW的混合降低了混合燃料燃烧反应的活化能。当TPW混合比例为80%时,混合燃料的活化能值最低,分别为111.32kJ/mol和104.87kJ/mol。TPW中丰富的碱金属离子和多孔结构降低了燃料中N和S元素向NO和SO2的转化率,从而减少了混合燃料的污染物排放。
    This paper investigates the combustion characteristics and pollutant emission patterns of the mixed combustion of lignite (L) and torrefied pine wood (TPW) under different blending ratios. Isothermal combustion experiments were conducted in a fixed bed reaction system at 800 °C, and pollutant emission concentrations were measured using a flue gas analyzer. Using scanning electron microscopy (SEM) and BET (nitrogen adsorption) experiments, it was found that torrefied pine wood (TPW) has a larger specific surface area and a more developed pore structure, which can facilitate more complete combustion of the sample. The results of the non-isothermal thermogravimetric analysis show that with the TPW blending ratio increase, the entire combustion process advances, and the ignition temperature, maximum peak temperature, and burnout temperature all show a decreasing trend. The kinetic equations of the combustion reaction process of mixed gas were calculated by Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) kinetic equations. The results show that the blending of TPW reduces the activation energy of the combustion reaction of the mixed fuel. When the TPW blending ratio is 80%, the activation energy values of the mixed fuel are the lowest at 111.32 kJ/mol and 104.87 kJ/mol. The abundant alkali metal ions and porous structure in TPW reduce the conversion rates of N and S elements in the fuel to NO and SO2, thus reducing the pollutant emissions from the mixed fuel.
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  • 文章类型: Journal Article
    CRISPR/Cas系统已被广泛用于核酸生物传感,并且由于crRNA的序列特异性而被进一步改进用于突变检测。然而,现有的基于CRISPR的基因分型方法受到Cas效应子的错配耐受性的限制,需要全面筛选crRNA以有效区分野生型和点突变序列。为了规避基于CRISPR的常规基因分型的局限性,在这里,我们通过实时数字CRISPR/Cas12a辅助测定(SMART-dCRISPR)介绍了单分子动力学分析。SMART-dCRISPR利用CRISPR/Cas系统中信号增加的差异动力学,其由crRNA和靶序列之间的互补性调节。它采用单分子数字测量来识别基于动力学曲线的突变,否则可能会被目标浓度的变化所掩盖。我们应用SMART-dCRISPR对SARS-CoV-2中的显著突变,点突变(K417N)和缺失(69/70DEL)进行了基因型分析,成功区分野生型,来自临床鼻咽/鼻拭子样品的OmicronBA.1和OmicronBA.2SARS-CoV-2菌株。此外,我们引入了一种便携式数字实时传感设备,以简化SMART-dCRISPR并增强其在即时护理环境中的实用性。快速和灵敏的基于CRISPR的等温测定与便携式形式的单分子动力学分析的组合显着增强了基于CRISPR的核酸生物传感和基因分型的多功能性。
    CRISPR/Cas systems have been widely employed for nucleic acid biosensing and have been further advanced for mutation detection by virtue of the sequence specificity of crRNA. However, existing CRISPR-based genotyping methods are limited by the mismatch tolerance of Cas effectors, necessitating a comprehensive screening of crRNAs to effectively distinguish between wild-type and point-mutated sequences. To circumvent the limitation of conventional CRISPR-based genotyping, here, we introduce Single-Molecule kinetic Analysis via a Real-Time digital CRISPR/Cas12a-assisted assay (SMART-dCRISPR). SMART-dCRISPR leverages the differential kinetics of the signal increase in CRISPR/Cas systems, which is modulated by the complementarity between crRNA and the target sequence. It employs single-molecule digital measurements to discern mutations based on kinetic profiles that could otherwise be obscured by variations in the target concentrations. We applied SMART-dCRISPR to genotype notable mutations in SARS-CoV-2, point mutation (K417N) and deletion (69/70DEL), successfully distinguishing wild-type, Omicron BA.1, and Omicron BA.2 SARS-CoV-2 strains from clinical nasopharyngeal/nasal swab samples. Additionally, we introduced a portable digital real-time sensing device to streamline SMART-dCRISPR and enhance its practicality for point-of-care settings. The combination of a rapid and sensitive isothermal CRISPR-based assay with single-molecule kinetic analysis in a portable format significantly enhances the versatility of CRISPR-based nucleic acid biosensing and genotyping.
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  • 文章类型: Journal Article
    这项研究的重点是详细检查醋酸纤维素纤维束(CAFB)的燃烧性能和动力学分析,从使用过的香烟过滤嘴中分离出来。结果表明,较快的CAFB加热速率允许在初始阶段向燃烧系统提供大量热量,其中加热速率的增加对点火行为具有正响应。CAFB的最佳燃烧稳定性是在最低加热速率下实现的。通过使用不同的动力学方法,结果表明,燃烧是通过两个连续的反应步骤和一个独立的单步反应进行的。通过优化所提出的反应模型内的动力学参数,发现与产生左旋葡聚糖酮(LGO)(通过左旋葡聚糖(LG)的催化脱水)和丙烯醛(通过CAFB燃烧过程中甘油的分解-这是通过甘油吸附在TiO2表面上进行的开发脱水机理)的步骤代表了速率控制步骤,这是由施加的加热速率强烈控制。等温预测表明,CAFB在60°C(相当于在海运集装箱中储存)下表现出非常好的长期稳定性,在200°C时,它显示了热稳定性的突然损失,这与样品的物理性质有关。
    This study is focused on the detailed examination of the combustion properties and kinetic analysis of a cellulose acetate fibrous bundle (CAFB), separated from used cigarette filters. It was shown that the faster rate of CAFB heating allows a large amount of heat to be supplied to a combustion system in the initial stages, where the increase in heating rate has a positive response to ignition behavior. The best combustion stability of CAFB is achieved at the lowest heating rate. Through the use of different kinetic methods, it was shown that combustion takes place through two series of consecutive reaction steps and one independent single-step reaction. By optimizing the kinetic parameters within the proposed reaction models, it was found that the steps related to the generation of levoglucosenone (LGO) (by catalytic dehydration of levoglucosan (LG)) and acrolein (by breakdown of glycerol during CAFB burning-which was carried out through glycerol adsorption on a TiO2 surface in a the developed dehydration mechanism) represent rate-controlling steps, which are strongly controlled by applied heating rate. Isothermal predictions have shown that CAFB manifests very good long-term stability at 60 °C (which corresponds to storage in a sea shipping container), while at 200 °C, it shows a sudden loss in thermal stability, which is related to the physical properties of the sample.
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  • 文章类型: Case Reports
    上交叉综合征(UCS)的特征是普遍存在的姿势功能障碍,涉及肩带和颈胸区肌肉组织的功能失调。胸锁乳突之间的不协调平衡,胸大肌,肩胛骨提肌,上斜方肌可能会导致颈椎不适,从而阻碍常规活动并促进UCS的发展。临床量表通常用于评估和监测康复进展;尽管如此,它们往往存在固有的局限性。相比之下,三维(3D)运动捕捉技术的进步提供了详细的运动学数据,从而增强了以更高的精度客观量化和阐明运动缺陷的能力。这个案例突出了采用Xsens作为结果度量的运动学分析来阐明UCS的复杂性的关键意义。从而为类似临床场景中的治疗干预提供宝贵的见解,并提供对运动生物力学的客观见解,肌肉功能,和功能限制。利用这些信息,临床医生可以巧妙地调整治疗方式,以解决潜在的肌肉骨骼失衡,最终优化患者结果。在这个案例研究中,我们检查了一名48岁的上班族持续头痛的运动学分析,运动范围受限,颈部和肩部疼痛超过四个月。尽管先前的干预,症状恶化,提示咨询神经物理治疗师。评估显示右肩局部疼痛,上背部,脖子,以逐渐发作和隐痛为特征,活动加剧,休息和药物缓解,没有昼夜波动。体检描绘了UCS特征。实施为期四周的理疗康复方案后,采用Xsens步态运动分析进行初步评估.在康复计划之后,注意到各种参数的显着改善。这些包含了增加的运动范围,增强肌肉力量,增强的灵活性。此外,在姿势和步态方面观察到明显的增强,其特点是恢复正常的颈椎曲度和扩大的活动范围。
    Upper crossed syndrome (UCS) characterizes a prevalent postural dysfunction involving dysfunctional tone in the musculature of the shoulder girdle and cervicothoracic region. The discordant balance among the sternocleidomastoid, pectoralis major, levator scapulae, and upper trapezius musculature potentially precipitated cervical discomfort, thereby hindering routine activities and fostering the progression of UCS. Clinical scales are routinely utilized to assess and monitor the progress of rehabilitation; nonetheless, they often present inherent limitations. In contrast, advancements in three-dimensional (3D) motion capture technology furnish detailed kinematic data, thereby augmenting the capacity to objectively quantify and elucidate movement deficits with heightened precision. This case highlights the critical significance of employing kinematic analysis with Xsens as an outcome measure to elucidate the intricacies of UCS, thereby offering invaluable insights for therapeutic interventions in similar clinical scenarios and providing objective insights into movement biomechanics, muscular function, and functional limitations. Leveraging this information, clinicians can skillfully tailor treatment modalities to address underlying musculoskeletal imbalances, ultimately optimizing patient outcomes. In this case study, we examine the kinematic analysis of a 48-year-old office worker experiencing persistent headaches, restricted range of motion, and neck and shoulder pain over a four-month period. Despite prior interventions, symptomatology deteriorated, prompting consultation with a neurophysiotherapist. The evaluation revealed localized pain in the right shoulder, upper back, and neck, characterized by gradual onset and dull ache, exacerbated by activity and alleviated by rest and medication, without diurnal fluctuations. Physical examination delineated UCS features. Following the implementation of a four-week physiotherapy rehabilitation protocol, initial assessments utilizing Xsens gait motion analysis were undertaken. Subsequent to the rehabilitation program, significant improvements were noted across various parameters. These encompassed augmented range of motion, heightened muscular strength, and enhanced flexibility. Additionally, discernible enhancements were observed in posture and gait, characterized by the restoration of normal cervical spine curvature and an expanded range of motion.
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  • 文章类型: Journal Article
    共热解是工业有机废物利用其独特的资源和能源特性高效转化为有价值产品的有前途的技术。这项研究是首次在实验室规模的固定床上表征废旧纺织品与富含Ca的工业污泥和富含Fe的工业污泥的共热解。属性,机制,气体,研究了油和碳的产量与温度和混合类型的关系。共热解将富含Ca的工业污泥与50%废旧纺织品混合的总重量损失从50.05%增加到69.81%,将富含Fe的工业污泥与50%废旧纺织品混合的总重量损失从49.13%增加到70.01%。与单独的废纺织品的热解相比,共热解的活化能低约50%。所有样品不同反应阶段的最佳反应模型为三扩散(D3)。共热解导致约25-110°C的较低CO和CO2排放温度,并产生更多的短链有机化合物(C<10)。共热解产生更多的醛和酮有机物。此外,共热解炭表现出高水平的脂肪烷基侧链和桥支化,以及更高的芳构化程度和稳定性。这项研究为热解在管理富含Ca/Fe的工业污泥和废旧纺织品方面的潜在应用提供了宝贵的见解。从而成为未来利用努力的基础。
    Co-pyrolysis is a promising technology for industrial organic waste to utilize their unique resource and energy properties for efficient conversion into valuable products. This study was the first time to characterize the co-pyrolysis of waste textiles with Ca-rich industrial sludge and Fe-rich industrial sludge on a laboratory-scale fixed bed. The properties, mechanisms, gas, oil and carbon production were investigated as a function of temperature and mixing type. Co-pyrolysis increased the total weight loss from 50.05 % to 69.81 % for Ca-rich industrial sludge mixed with 50 % waste textiles and from 49.13 % to 70.01 % for Fe-rich industrial sludge mixed with 50 % waste textiles. The activation energy of co-pyrolysis was approximately 50 % lower compared to the pyrolysis of waste textiles alone. The optimal reaction model for the different reaction stages for all samples was three diffusion (D3). Co-pyrolysis resulted in lower CO and CO2 emission temperatures of about 25-110 °C and produced more short-chain organic compounds (C < 10). Co-pyrolysis produced more aldehydes and ketones organics. Moreover, co-pyrolysis char exhibited an elevated level of fatty alkyl side chains and bridge branching, as well as higher degrees of aromatization and stability. This study offers valuable insights into the potential application of pyrolysis for the management of Ca/Fe-rich industrial sludge and waste textiles, thereby serving as a basis for future utilization endeavors.
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  • 文章类型: Journal Article
    厌氧消化(AcoD)与厨房垃圾(KW)是藻类水华废物(AW)的替代利用策略。然而,此过程的动力学特征和代谢途径有待进一步探索。本研究对AW和KW的AcoD进行了全面的动力学和宏基因组分析。在12%AW添加下,实现了1.13的最大共消化性能指数(CPI)。共消化提高了总挥发性脂肪酸的生成和有机物的转化效率。动力学分析表明,叠加模型拟合最佳(R2Adj=0.9988-0.9995)。共消化对动力学过程的改善主要体现在缓慢生物降解成分的甲烷产量增加。共消化富集了纤维素分解细菌梭菌和氢营养产甲烷古细菌甲烷杆菌。此外,用于宏基因组分析,纤维素和脂质水解中涉及的关键基因的丰度,在共消化过程中,丙酮酸和甲烷代谢均增加。这项研究为利用季节性产生的AW提供了可行的过程,并从动力学和宏基因组的角度更深入地了解了AcoD的协同机制。
    Anaerobic co-digestion (AcoD) with kitchen waste (KW) is an alternative utilization strategy for algal bloom waste (AW). However, the kinetic characteristic and metabolic pathway during this process need to be explored further. This study conducted a comprehensive kinetic and metagenomic analysis for AcoD of AW and KW. A maximum co-digestion performance index (CPI) of 1.13 was achieved under the 12% AW addition. Co-digestion improved the total volatile fatty acids generation and the organic matter transformation efficiency. Kinetic analysis showed that the Superimposed model fit optimally (R2Adj = 0.9988-0.9995). The improvement of the kinetic process by co-digestion was mainly reflected in the increase of the methane production from slowly biodegradable components. Co-digestion enriched the cellulolytic bacterium Clostridium and the hydrogenotrophic methanogenic archaea Methanobacterium. Furthermore, for metagenome analysis, the abundance of key genes concerned in cellulose and lipid hydrolysis, pyruvate and methane metabolism were both increased in co-digestion process. This study provided a feasible process for the utilization of AW produced seasonally and a deeper understanding of the AcoD synergistic mechanism from kinetic and metagenomic perspectives.
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  • 文章类型: Journal Article
    RNA诱导的沉默复合物(RISC),为RNA干扰(RNAi)提供动力,由向导RNA和Argonaute蛋白组成,该蛋白对与向导互补的靶向RNA进行切片。我们发现,对于不同的引导RNA序列,完全互补的切片率,结合的目标可以是惊人的不同(>250倍范围),更快的切片赋予细胞更好的击倒。指导RNA位置7、10和17处的核苷酸序列同一性是切片速率中这种变化的大部分基础。对这些决定簇之一的分析暗示了在促进切片中指导核苷酸6-7处的结构畸变。此外,由不同的引导序列引导的切片具有意想不到的,在3'-失配容限范围内的600倍,归因于具有弱(富含AU)中央配对的指南,需要广泛的3'互补性(超过位置16的配对)才能更充分地填充切片能力的构象。一起,我们的分析确定了RISC活性的序列决定因素,并提供了其作用的生化和构象原理.
    结论:•指导RNA的序列可以将完全配对的底物的切片速率改变250倍•导致更快速切片的序列直接在细胞中更有效的RNAi•强烈的中心配对赋予对指导3'区域的错配的耐受性•这种耐受性归因于更充分地填充切片构象。
    The RNA-induced silencing complex (RISC), which powers RNA interference (RNAi), consists of a guide RNA and an Argonaute protein that slices target RNAs complementary to the guide. We find that for different guide-RNA sequences, slicing rates of perfectly complementary, bound targets can be surprisingly different (>250-fold range), and that faster slicing confers better knockdown in cells. Nucleotide sequence identities at guide-RNA positions 7, 10, and 17 underlie much of this variation in slicing rates. Analysis of one of these determinants implicates a structural distortion at guide nucleotides 6-7 in promoting slicing. Moreover, slicing directed by different guide sequences has an unanticipated, 600-fold range in 3\'-mismatch tolerance, attributable to guides with weak (AU-rich) central pairing requiring extensive 3\' complementarity (pairing beyond position 16) to more fully populate the slicing-competent conformation. Together, our analyses identify sequence determinants of RISC activity and provide biochemical and conformational rationale for their action.
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