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61.
Lipid droplets (LDs) are ubiquitous cellular organelles for lipid storage which are composed of a neutral lipid core bounded by a protein decorated phospholipid monolayer. Although lipid storage is their most obvious function, LDs are far from inert as they participate in maintaining lipid homeostasis through lipid synthesis, metabolism, and transportation. Furthermore, they are involved in cell signaling and other molecular events closely associated with human disease such as dyslipidemia, obesity, lipodystrophy, diabetes, fatty liver, atherosclerosis, and others. The last decade has seen a great increase in the attention paid to LD biology. Regardless, many fundamental features of LD biology remain obscure. In this review, we will discuss key aspects of LD biology including their biogenesis, growth and regression. We will also summarize the current knowledge about the role LDs play in human disease, especially from the perspective of the dynamics of the associated proteins. This article is part of a Special issue entitled Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers. 相似文献
62.
Biotransformation of linear alkylbenzene sulfonate (LAS) by Phanerochaete chrysosporium: oxidation of alkyl side-chain 总被引:2,自引:0,他引:2
The white rot fungus Phanerochaete chrysosporium, which generally mineralizes substituted aromatics to CO2, transformed linear alkylbenzene sulfonate (LAS) surfactants mainly at their alkyl side chain. Degradation of LAS was evidenced by a zone of clearing on LAS-containing agar plates and colorimetric analysis of liquid cultures. Disappearance of LAS was virtually complete within 10 days in low nitrogen (2.4 mM N), high nitrogen (24 mM N) and malt extract (ME) liquid media. After 5 days of incubation in ME medium, transformation of LAS was complete at concentrations4 mg l-1, but decreased at higher concentrations. The LAS degradation was not dependent on lignin peroxidases (LiPs) and manganese-dependent peroxidases (MnPs). Mineralization of14C-ring-LAS to 14CO2 by P. chrysosporium was <1% regardless of the culture conditions used. Thin layer chromatography and mass spectral analyses indicated that P. chrysosporium transformed LAS to sulfophenyl carboxylates (SPCs) through oxidative shortening of the alkyl side-chains. While LAS disappearance in the cultures was not dependent on LiPs and MnPs, transformation of the parent LAS moieties to SPCs was more extensive in low N medium that favors expression of these enzymes. The SPCs produced in LN cultures were shorter in chain-length than those produced in ME cultures. Also there was a notable shift in the relative abundance of odd and even chain length metabolites compared to the starting LAS particularly in the low N cultures suggesting the possible involvement of processes other than or in addition to-oxidation in the chain-shortening process. 相似文献
63.
64.
B.R. Vázquez‐de‐Aldana M. Romo A. García‐Ciudad C. Petisco B. García‐Criado 《The Annals of applied biology》2011,159(2):281-290
Red fescue (Festuca rubra) is a perennial grass used as both forage and turfgrass. Asymptomatic plants of this species are systemically infected by the fungal endophyte Epichloë festucae, which has a beneficial effect on the infected plants. The aim of this study was to determine the effect of the endophyte Epichloë festucae on the allelopathic potential of F. rubra against four associated pasture species that are also considered as weeds in lawns, Trifolium pratense, Trifolium repens, Lotus corniculatus and Plantago lanceolata. Two experiments were designed to evaluate the allelopathic effect of extracts from the roots and leaves of endophyte‐infected (E+) and non‐infected (E?) plants on the germination and seedling growth of the four target species. Regardless of the endophyte status of the host plant, leaf extracts elicited a stronger reduction in germination and seedling growth than root extracts. Extracts from E+ plants reduced the speed of germination index of Trifolium spp. to a greater extent than those from E? plants. Radicle length of the target species was the parameter most affected by the presence of the endophyte in F. rubra. Root extracts from E+ plants had a greater inhibitory effect on the radicle growth of the target species than did root extracts from E? plants. A greater concentration in total phenolic compounds was found in the roots of E+ plants than of E?; however, this difference was not observed in the leaves. Thus, the allelopathic potential of F. rubra is altered in infected plants. 相似文献
65.
原位杂交研究对虾白斑杆状病毒在虾体内感染过程 总被引:7,自引:0,他引:7
应用地高辛标记的对虾白斑杆状病毒(white spot syndrome baculovirus,WSSV)核酸探针,与人工感染后不同时间采集的对虾组织样品进行原位杂交,以动态研究病毒从侵染至对虾以病死亡的过程。将典型感染WSSV的病虾组织投喂健康对虾,结果显示:WSSV道德通过侵染消化道上皮进入虾体内增殖,此后随着细胞裂解、病毒粒子释放,游离的粒子伴随血淋巴循环进而杂其它靶组织,直至对虾发病死亡 相似文献
66.
67.
徽州稻区作为我国白背飞虱北迁与南迁的重要中转站之一,地理位置十分特殊,分析其中、晚稻田白背飞虱种群动态及虫源性质,对皖南稻区乃至江淮稻区白背飞虱预测预报和防治工作意义重大。通过田间系统调查和长翅雌虫卵巢解剖,研究了徽州稻区白背飞虱种群消长及虫源性质。运用GrADS和ArcGIS分析2009年白背飞虱主要迁入期的天气背景,并利用HYSPLIT轨迹模拟平台对主要迁入期进行数值模拟和虫源地分析。结果表明:2009年徽州稻区白背飞虱在中、晚稻以第3代危害为主。中稻田第2—4代白背飞虱属于基本迁出型,同时第3代前半期还存在部分滞留本地繁殖或者是外地白背飞虱迁入现象;而晚稻第3代后半期白背飞虱属于基本迁入型,第4—5代属于基本迁出型。风切变、下沉气流和强降水可作为徽州稻区预测白背飞虱迁入的气象背景。2009年徽州稻区白背飞虱虫源地主要分布在湘南、赣中及赣南。 相似文献
68.
Waqar Jaleel Shafqat Saeed Qamar Saeed Muhammad Nadir Naqqash Muhammad Umair Sial Qurat Ul Aine Lei Yanyuan Zhao Rui Yurong He Lihua Lu 《Entomological Research》2019,49(4):151-157
Plutella xylostella is an important pest of cruciferous crops worldwide. However, information regarding the age‐stage, two‐sex life parameters of P. xylostella, which is vital for designing more effective control methods, is currently lacking. The present study reports age‐stage, two‐sex life table parameters for P. xylostella on napa cabbage (Brassica oleracea var. napa), white cabbage (B. oleracea var. capitata), and cauliflower (B. oleracea var. botrytis) under laboratory conditions at 25 ± 2°C, 50–60% relative humidity, and a 16‐h light : 8‐h dark photoperiod. The time for development from an egg to a male or female adult P. xylostella on white cabbage (mean [± SE] 41.15 ± 0.54 and 39.50 ± 0.54 days, respectively) was significantly longer than that on cauliflower and napa cabbage. Furthermore, P. xylostella fecundity on cauliflower (261.90 ± 4.53 eggs female) was significantly highest than on napa cabbage and white cabbage. Intrinsic rate of increase (r) and finite rate of increase (λ) were highest on cauliflower 0.182 day?1 and 1.199 day?1 respectively as comparison to napa cabbage and white cabbage. The highest gross reproductive rate (GRR) and net reproductive rates (R0) of P. xylostella 65.87 and 52.58 respectively on cauliflower then those of other hosts. The findings of the present study indicate that cauliflower is the most suitable cultivar (host) for the development of P. xylostella. Based on these findings, crops like cauliflower can be used as trap crops when napa cabbage and white cabbage are the main crops. 相似文献
69.
马立克氏病病毒超强毒感染鸡羽髓蛋白质组分析 总被引:1,自引:0,他引:1
【目的】羽毛是细胞游离马立克氏病病毒(Marek’s disease virus,MDV)释放的部位,为了解感染MDV后鸡羽中宿主基因表达的变化及对病毒感染的应答,进行了MDV感染鸡的羽髓蛋白质组学分析。【方法】1日龄无特定病原体(specific pathogen free,SPF)鸡人工感染MDV超强毒RB1B株(1000PFU),感染后21d采集鸡羽毛,提取羽髓蛋白,以17cm,pH5-8的IPG胶条进行二维电泳,以未感染病毒的SPF鸡羽髓蛋白为对照,使用PDQuest软件对二维电泳图谱进行差异蛋白分析,并选取部分差异斑点进行质谱鉴定。【结果】PDQuest软件分析发现攻毒组和对照组表达差异大于两倍的蛋白点有41个,其中攻毒组表达上调的蛋白点25个,下调的蛋白点7个,新出现的蛋白点有9个。质谱分析共成功鉴定了21个斑点,对应于20个蛋白。如载脂蛋白AI(apolipoprotein AI)、14-3-3 sigma(两个斑点均为该蛋白)、癌蛋白18(stathmin)等。【结论】功能预测表明这些蛋白涉及到宿主的抗病毒应答、物质代谢、细胞骨架成分、细胞增殖相关等方面。 相似文献
70.
白腐菌对培养环境pH的调节及其产漆酶的相关性 总被引:2,自引:1,他引:2
研究了不同种属白腐菌多孔菌属C1(Polyporussp.)、侧耳属B2(Pleurotussp.)、香菇属A3(Lentinusedodes)对培养环境pH的调节,及其与菌株产漆酶状况的相关性。结果表明:3株白腐菌均可调节培养液酸化,培养环境的pH可分别由初始的4.5~5.0持续下降至培养结束时3.0~3.5水平,相应C1、B2、A3三者的漆酶合成与分泌在pH值较高(pH 4.5以上)时均表现较弱(酶活分别处于约1 500、200、50 U/mL以下的水平),在pH 3.2~4.5范围内的不同偏酸性条件下则得到较好表达(最高酶活分别达5 000、340、144 U/mL)。统计学分析指出,白腐菌调节环境pH状况与其产漆酶状况之间存在显著或极显著相关性,但不同白腐菌调节培养环境pH的能力之间并不具有显著性差异。 相似文献