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51.
52.
【目的】明确沃尔巴克氏菌Wolbachia对茶尺蠖两近缘种杂交卵孵化的影响及相关机制。【方法】使用2.5 mg/mL四环素浸液处理1 min后的新鲜茶树叶片连续饲喂灰茶尺蠖Ectropis grisescens幼虫3代,建立不携带Wolbachia的灰茶尺蠖种群。通过携带和不携带Wolbachia的灰茶尺蠖成虫分别与小茶尺蠖E.obliqua成虫进行杂交,探究Wolbachia对二者杂交卵孵化的影响。同时利用iTRAQ技术检测并分析携带和不携带Wolbachia的灰茶尺蠖精子蛋白的差异。【结果】与自然携带Wolbachia的灰茶尺蠖相比,去除Wolbachia后的灰茶尺蠖与小茶尺蠖杂交卵孵化率从3.92%显著提高到56.20%,表明Wolbachia诱导胞质不亲合。精子蛋白差异分析显示,携带和不携带Wolbachia的灰茶尺蠖的精子蛋白中,共有128个蛋白显著差异表达,其中KEGG数据库注释到45个差异蛋白富集到鞘脂类代谢、唾液分泌、溶酶体、鞘脂信号通路和鞘糖脂生物合成等106个通路中,其中鞘脂类代谢通路中与神经酰胺合成相关的神经酰胺酶和磷酸酯酶显著上调表达。【结论】共生菌Wolbac...  相似文献   
53.
沙棘木蠹蛾卵和幼虫空间分布的地统计学分析   总被引:13,自引:3,他引:13  
沙棘木蠹蛾(H olcocerushippophaecolus Hua,Chou ,Fang et Chen)是近几年在内蒙古、辽宁、山西、宁夏和陕西等地大面积爆发的一种钻蛀性害虫,其危害发生在幼虫期,主要危害沙棘(H ippophae rhamnoidea)的根干部。为了有效地控制其危害,深入了解种群的空间结构,利用地统计学方法分析了两种受害程度不同的林分内沙棘木蠹蛾幼虫种群和重度受害林分内卵块的空间分布特性。结果表明:两种受害程度不同的林分内,沙棘木蠹蛾的危害具有显著差异,轻度受害林分内无虫样本所占的比例较大,达70 % ,而重度受害林分内不到2 0 % ;虫口密度在轻度受害林分内超过6头/株的只有6 .9% ,而重度受害林分内高达31.9%。根据全方向的变异函数曲线图分析得知:重度受害林分和轻度受害林分内幼虫种群的空间依赖范围分别为7.3m和87.4 18m,而局部空间连续性强度分别为0 .914和0 .178。重度受害林分内幼虫表现较强的空间聚集性,而轻度受害林分则表现为随机分布。在重度受害林分中,单株沙棘树上沙棘木蠹蛾卵块数量最多的为11个,最少的为1个,有卵株率达72 %。分别采用四种不同的理论模型来拟合卵块的实际变异曲线图,得知其全方向的变异函数曲线为指数型,空间依赖范围大小为3.6 m,局部空间连续性强度为0 .876 ,卵块在重度受害林分中呈现较强  相似文献   
54.
Synopsis Social organization and spawning in the sharpnose pufferCanthigaster rostrataere studied on a reef in the San Blas Islands, Panama. Sexes were dimorphic. In mixed coral and rubble habitat, females defended territories against other females and small males. From one to six female territories were included within the territories of certain large males. These haremic males visited their females and patrolled their territories throughout the day. Smaller, non-haremic males occupied territories or home ranges within or adjacent to those of haremic males or were wanderers. Spawning between a haremic male and a territorial female occurred within the female's territory. The female prepared an algal nest into which demersal eggs were deposited. There was no parental care. Eggs were spherical, translucent, and measured approximately 0.66 mm in diameter. Larvae were about 1.4 mm TL and closely resembled those of other species ofCanthigaster.  相似文献   
55.
绿盲蝽捕食棉铃虫卵的CO Ⅰ标记检测方法   总被引:1,自引:0,他引:1  
绿盲蝽Apolygus lucorum Meyer-Dür不仅取食棉花等多种农作物,而且还具有一定的捕食行为。利用棉铃虫细胞色素氧化酶Ⅰ(COⅠ)的基因序列,设计了检测绿盲蝽对棉铃虫Helicoverpa armigera Hübner卵捕食作用的特异引物。PCR分析结果表明,该引物可特异性检测绿盲蝽体内棉铃虫卵DNA片段,取食3粒棉铃虫卵绿盲蝽的检测半衰期为1.77 h。此检测方法为进一步评价绿盲蝽在农业生态系统中的地位与功能提供了技术平台。  相似文献   
56.
Synopsis We studied the timing of migratory fish spawning in the last dam-free stretch of the upper Paraná River and in Itaipu Reservoir. Eggs were more common in the Amambai and Ivaï Rivers, while larvae predominated in the Paraná River and in Itaipu Reservoir. Both eggs and larvae were more abundant at night. The highest abundance of eggs was in October and that of larvae in November. Migratory species predominated in the Amambai and Paraná Rivers, and non-migratory species in the Ivaï River and Itaipu Reservoir. The predominance of eggs in the upper and middle portions, and larvae in the lower, infer that there are spawning sites in the former and nurseries in the latter. The high nocturnal abundance of eggs is associated with spawning at sunset and that of larvae with feeding, avoidance of predators and nocturnal disorientation. The presence of tributaries such as the Amambai and Ivaí Rivers in the last dam-free stretch of the Paraná River is extremely important to the maintenance of regional fish diversity and fish stocks in both the Paraná River and Itaipu Reservoir.  相似文献   
57.
Mouse egg activation, which includes release from meiotic metaphase II arrest, results from fertilization-induced increase in intracellular calcium concentration ([Ca2+]i). However, during egg activation caused by exposure to the protein synthesis inhibitor, cycloheximide, [Ca2+]i did not change. Although eggs fertilized in the presence of microtubule inhibitors remain arrested at metaphase, eggs treated for 32 hr with cycloheximide and the microtubule inhibitor, colcemid, formed nuclei. In untreated eggs aged in culture for 24 hr, the microtubule spindles became deformed. These eggs formed nuclei after exposure to cycloheximide, but not the calcium ionophore A23187. Our results indicate that eggs in which protein synthesis is inhibited are released from metaphase without an increase in [Ca2+]i, and despite disruption of the Spindle. © 1995 Wiley-Liss, Inc.  相似文献   
58.
To initiate embryo development, the sperm induces in the egg release of intracellular calcium ([Ca2+]i). During oocyte maturation, the inositol 1,4,5-trisphosphate receptor (IP3R1), the channel implicated, undergoes modifications that enhance its function. We found that IP3R1 becomes phosphorylated during maturation at an MPM-2 epitope and that this persists until the fertilization-associated [Ca2+]i responses cease. We also reported that maturation without ERK activity diminishes IP3R1 MPM-2 reactivity and [Ca2+]i responses. Here, we show that IP3R1 is a novel target for Polo-like kinase1 (Plk1), a conserved M-phase kinase, which phosphorylates it at an MPM-2 epitope. Plk1 and IP3R1 interact in an M-phase preferential manner, and they exhibit close co-localization in the spindle/spindle poles area. This co-localization is reduced in the absence of ERK activity, as the ERK pathway regulates spindle organization and IP3R1 cortical re-distribution. We propose that IP3R1 phosphorylation by Plk1, and possibly by other M-phase kinases, underlies the delivery of spatially and temporally regulated [Ca2+]i signals during meiosis/mitosis and cytokinesis.  相似文献   
59.
为研究蛋白激酶C(protein kinase C,PKC)在小鼠早期发育中的调节作用,运用超排卵和体外受精技术,采用体外磷酸化和放射自显影的方法,鉴定小鼠1-细胞期受精卵中PKC的底物。经特殊的反复冻融处理,消除卵中内源性蛋白激酶活性。55个受精卵的样品中加入部分纯化的PKC,结合应用较强的PKC抑制剂H-7和星形孢菌素以及促分裂原活化蛋白激酶抑制剂PD098059作为对照,观察到12条PKC底物蛋白的放射自显影带,根据标准蛋白质对值绘制的标准曲线计算,这些磷酸化蛋白的相对分子量分别约为120kDa、100kDa、79kDa、63kDa、59kDa、47kDa、40kDa、34kDa、32kDa、26kDa、24kDa和22kDa。实验结果表明,PKC可通过底物蛋白活性的调节,在小鼠早期发育中发挥重要作用。  相似文献   
60.
Summary

A mated Amblyomma hebraeum female will engorge on a host for about 8 days before detaching and beginning the maturation of its single egg batch which is laid during a period of about 30 days. The feeding period is characterized by an important synthesis of endocuticular material occurring before the rapid feeding phase. This latter phase, correlated with an enormous weight uptake, shows an increase of ecdysteroid levels measured in the whole animal by RIA. However, the hemolymphatic levels of ecdysteroids remain very low (12 pg 20-hydroxyecdysone equivalent (20-OH-E eq.) per μ1. Within 4 days after detachment, the salivary glands degenerate. Ecdysteroid levels in the whole animal continue to increase, reaching high values (about 500 ng 20-OH-E eq./tick) at the moment of oviposition which begins 10–14 days after dropping. During the same period, hemolymphatic ecdysteroid levels increase, rising to a peak (600 pg 20-OH-E eq./μ1) 1 day prior to the beginning of oviposition. Then, the levels decrease and stabilize around 250 pg 20-OH-E eq./μl during egg-laying. Freshly laid eggs contain large amounts of ecdysteroids (2744 pg 20-OH-E eq./mg).

20-Hydroxyecdysone and ecdysone have been found to be the major free ecdysteroids in hemolymph, ovaries and eggs (verified by the HPLC-RIA technique and GC-MF of silylated HPLC fractions). Helix juice (or esterase) labile ecdysteroid conjugates do not seem to be present to any noticeable extent in hemolymph, ovaries and eggs.  相似文献   
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