应用iTRAQ结合2D LC-MS/MS技术分析草菇同核和异核菌丝蛋白质组

首次利用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantification,iTRAQ)技术结合二维液相色谱串联质谱对草菇(Volvariella volvacea)同核和异核菌丝蛋白质组进行研究。采用QExactive质谱鉴定并经MASCOT软件搜库,对所有鉴定蛋白进行主成分分析(principal component analysis,PCA)、层次聚类(hierarchical clustering)分析和GO(gene ontology)注释,并进行生物信息学分析。结果共获得2335个不同肽段,鉴定到1039个蛋白,其中1030个蛋白具有定量信息。在同核菌丝中显著上调蛋白83个,下调蛋白97个,表明iTRAQ标记技术结合二维液相色谱串联质谱可有效地分离和鉴定草菇菌丝蛋白质组。该研究结果为更深入全面地研究草菇菌丝蛋白质组学奠定基础。     

The use of digital image analysis and real‐time PCR fine‐tunes bioassays for quantification of Cercospora leaf spot disease in sugar beet breeding

Cercospora leaf spot, caused by the fungus Cercospora beticola, is a major fungal sugar beet disease worldwide and the cause of significant yield losses. The disease is most successfully countered by the introduction of genetic tolerance into elite sugar beet hybrids. To this end, breeding programmes require high quality biological assays allowing discrimination of minor differences between plants within a segregating population. This study describes the successful implementation of image analysis software in the bioassays for quantification of necrotic lesions at different stages of C. beticola infection, allowing selection on minor phenotypic differences during the sugar beet breeding process for C. beticola resistance. In addition, a real‐time PCR assay was developed for the quantification of C. beticola pathogen biomass in infected beet canopy. The use of both techniques, even in an early stage of infection, fine‐tunes current bioassays, allowing more accurate and efficient selection of resistant breeding material.     

实时定量PDR技术研究进展及其在小麦转基因检测中的应用

综述了实时定量PCR的原理、定量方法、主要特性及其在小麦转基因检测中的应用,概述了其发展前景。     

Use of computerized image analysis to quantify staphylococcal adhesion to canine corneocytes: does breed and body site have any relevance to the pathogenesis of pyoderma?

An optimized system of computerized image analysis was used to investigate variations in the adherence of Staphylococcus intermedius to canine corneocytes from four different breed groups and six different anatomical sites. S. intermedius showed significantly greater adherence to the head and neck compared with the dorsum, but adherence to the limb, axilla and groin did not differ from other sites. Furthermore, there was significantly greater adherence of S. intermedius to corneocytes from the dorsum, forelimb, axilla and groin of Boxers and Bull Terriers than Spaniels and Hounds. S. intermedius, and also Pseudomonas aeruginosa, exhibited abundant adherence, which was significantly greater than Staphylococcus aureus, Streptococcus canis, Klebsiella pneumoniae and Escherichia coli. In addition, S. intermedius adherence demonstrated a sigmoid dose-response curve with increasing bacterial concentration. These results suggest that S. intermedius adheres to canine corneocytes by a specific receptor-ligand interaction and adheres to the skin of some breeds more avidly than others. However, variations in adherence between body regions would not account for the predilection sites of canine bacterial pyoderma.     

Quantification of airborne spores of <Emphasis Type="Italic">Monilinia fructicola</Emphasis> in stone fruit orchards of California using real-time PCR

The fungal pathogen Monilinia fructicola causes blossom blight and fruit brown rot of stone fruits in California. In this study, spore densities in the air were monitored in six orchard/year combinations with Burkard spore traps. A real-time PCR assay was developed to efficiently quantify the dynamics of spore density in these orchards during the growing season. Different patterns of dynamics of spore density were observed in these orchards. A linear relationship between numbers of spores counted with a compound microscope and those determined with the real-time PCR assay was obtained, using the same samples of spore traps. Spore density in five of six orchard/year combinations ranged from 0.0 to 0.05 spores l⁻¹, except for that in orchard 4, which showed much higher values of spore density in the air, as well as higher values and wider range of incidences of blossom infection and fruit rot than those in the other orchards. The results demonstrated a potential method to quantitatively determine spore inoculum potential in orchards by using a real-time PCR assay.     

Heterogeneity of the aerial concentration and deposition of ascospores of <Emphasis Type="Italic">Venturia inaequalis</Emphasis> within a tree canopy during the rain

Scab is an important disease of apple and its control depends almost exclusively on frequent use of fungicides. Primary scab infection in the spring assumes several steps: ascospore maturation, liberation of ascospores that become airborne, deposition on susceptible tissues, and infection. However, the spatial heterogeneity of ascospores within the tree canopy is unknown. Aerial concentration of ascospore (ACA), ascospore concentration in rain water (ACR) and ascospore deposition (AD) were therefore measured at six heights (20–257 cm from the ground) with rotating-arm air samplers, funnels, and greased glass slides, respectively, during five rain events in 2001 and in 2002. In addition, ACR and AD were measured at eight locations within tree canopy at 196 cm height. Apple scab was assessed at the end of the primary infection period in each sampling location within the apple tree. A similar experimental design was used in 2003 to study the spatial heterogeneity of both AD and primary scab lesions. ACA and AD decreased with increasing height, while ACR increased with increasing height. Based on both variance to mean ratio and the power law relationship in both years, the ACR was heterogeneous, while AD was heterogeneous only during the peaks of ascospore release. The ACR was significantly higher at the centre of the trees and the AD was significantly higher at the centre and at the western edge of the trees. Only the cumulative AD was significantly correlated with apple scab lesions at the same location (r = 0.83). In 2003, a similar pattern of spatial heterogeneity within the tree canopy was observed for AD and primary scab lesion counts and there was a linear relationship (R ² = 0.84) between these two variables. It was concluded that ACR and AD within the tree canopy are not randomly distributed at least during peaks of ascospore release and that AD is a good estimate of primary scab lesion development. This spatial heterogeneity should be considered when estimating ascospore deposition using mathematical models or when quantifying ascosporic inoculum using spore samplers.     

竞争性PCR定量检测鸡传染性贫血病毒核酸

将删除33个碱基序列的CAVDNA克隆进质粒pSBII,提取质粒DNA,经过纯化、定量后作为竞争性模板,建立了一种定量检测鸡传染性贫血病毒核酸方法。该方法能够检测出的最低CAVDNA为103.5Molecules/μL,其精确度可达到100.5Molecules/μL。该方法与传统方法相比,具有节省时间、节约试剂和受其它因素干扰小等特点。     

小麦品种抗性多样化中寄主群体抗性量化的研究

 在一个地区范围内利用病原群体毒性及寄主群体抗性的观点,可把多个具不同抗锈性小麦品种在不同布局条件下,将其整体抗性加以综合量化,其结果在预测预报小麦锈病流行强度的研究中,有助于品种抗性因子对锈病流行强度所产生干扰作用的大小能够量化进入预测式.     

应用数量化理论Ⅰ分析和田护田林带的防风作用

本文应用数量化理论Ⅰ这一数学分析方法,阐明农防林防风效益的普遍规律及其特点,并予以科学地评价。通过对依变量(林带背风面不同距离的风速相对值和透风系数)与自变量(疏透度、大气热层结、风向交角和风力等级)之间变化的分析,依据各自变量的得分范围,偏相关系数,定量说明各自变量对依变量的贡献。结果依变量的变化与自变量中疏透度的变化相关最为密切,其余自变量则依次排列。疏透度是人为所能控制和调解的,而其余因子对防风作用的影响则可以通过大面积推广窄林带小网格的林网化建设,建立综合防护林体系而积极产生作用,使其影响降低到极小程度,最大地发挥林带本身的防风效果。     

评价回归模型拟合效果的数量化方法

回归模型模拟的效果直接影响其预测结果的精确性，针对残差分析法检验模型似合效果的局限性，采用数量化方法进行检验，不仅综合分析的模拟效果，而且可以直接比较模型间的拟合效果，并为建立拟合效果好的新模型提供了充分的依据。