大白公猪精浆外泌体miRNA表征鉴定及功能分析

【目的】精浆外泌体(Seminal plasma exosome,spEX)在精子成熟、凋亡、受精中起着至关重要的作用。本文旨在探究种公猪spEX miRNA表达及miRNA在精子成熟及功能维持过程中的潜在调控作用。【方法】提取大白公猪spEX并进行电镜分析、粒径分析、标志性蛋白表达分析和miRNA高通量测序。【结果】成功分离出spEX，利用miRNA测序共鉴定出329个spEX miRNA。对高表达miRNA进行靶基因预测和功能富集分析，结果表明spEX miRNA在射精、P53信号通路、前列腺癌、细胞对DNA损伤刺激的反应、负调控凋亡过程、顶体膜结合、受精等通路中均发挥了潜在调控作用。【结论】本研究为spEX miRNA在调控精子活力和精子受精作用方面提供基础数据，并为精液保存调控机制的研究提供参考。     

The signal to move: D. discoideum go orienteering

Cells migrating directionally toward a chemoattractant source display a highly polarized cytoskeletal organization, with F-actin localized predominantly at the anterior and myosin II at the lateral and posterior regions. Dictyostelium discoideum has proven a useful system for elucidating signaling pathways that regulate this chemotactic response. During development, extracellular adenosine 3', 5' monophosphate (cAMP) functions as a primary signal to activate cell surface cAMP receptors (cARs). These receptors transduce different signals depending on whether or not they are coupled to heterotrimeric guanine nucleotide-binding proteins (G proteins) (see the STKE Connections Maps). Multiple G protein-stimulated pathways interact to establish polarity in chemotaxing D. discoideum cells by localizing F-actin at their leading edge and by regulating the phosphorylation state and assembly of myosin II. Many of the molecular interactions described are fundamental to the regulation of chemotaxis in other eukaryotic cells.     

不同因素对牛卵母细胞胞质内精子注射效果的影响

采用胞质内精子注射法（ICSI）构建牛显微受精胚胎,探讨卵母细胞成熟培养时间、精子状态及精子操作液中聚乙烯吡咯烷酮（PVP）浓度对牛卵母细胞胞质内显微受精（ICSI）卵体外发育的影响。结果显示：成熟培养20 h、24 h和28 h的卵母细胞用于ICSI时,ICSI卵的形态完整率分别为94.6%（175/185）、97.2%（173/178）和96.4%（189/196）（P〉0.05）;成熟培养24 h和28 h的卵母细胞,其ICSI卵的卵裂率（73.4%和70.9%）和囊胚发育率（31.8%和29.6%）显著高于成熟培养20 h的卵母细胞（61.1%和20.6%）（P〈0.05）。对成熟培养24 h的卵母细胞注射获能精子时,ICSI卵的卵裂率和囊胚发育率（72.7%和31.4%）高于未获能精子组（69.4%和29.3%）和不运动精子组（71.5%和30.4%）,但无统计学差异（P〉0.05）。采用含5%,10%和15%PVP的精子操作液处理获能精子后对成熟培养24 h的卵母细胞进行ICSI操作,PVP浓度为5%和10%时,ICSI卵的卵裂率（73.2%和66.9%）和囊胚发育率（32.7%和29.7%）差异不显著（P〉0.05）,但二者均显著高于15%PVP浓度组的卵裂率和囊胚发育率（51.0%和16.3%）（P〈0.01）。结论认为,选用获能精子,并使用含5%PVP的精子操作液进行处理,对成熟培养24 h的牛卵母细胞进行ICSI操作,有利于ICSI卵的体外发育。     

霍奎耶羊驼皮肤毛囊兴盛期结构分析

为阐明羊驼绒毛生长发育提供组织学基础,同时也为毛用动物的遗传改良提供重要的理论依据,通过制作霍奎耶羊驼皮肤组织切片,在显微镜下观察其毛囊兴盛期结构,结果表明霍奎耶羊驼的毛囊结构同其他动物一样,由毛球、连接组织鞘、内根鞘、外根鞘和毛干几部分组成.兴盛期毛囊直径从上到下逐渐增大,末端膨大为毛球,呈一漏斗状,毛球内陷深入形成毛乳头.毛囊群中毛囊的数量较多,且由少量的结缔组织分为两小群.     

The phosphoinositide 3-kinase pathway

Phosphorylated lipids are produced at cellular membranes during signaling events and contribute to the recruitment and activation of various signaling components. The role of phosphoinositide 3-kinase (PI3K), which catalyzes the production of phosphatidylinositol-3,4,5-trisphosphate, in cell survival pathways; the regulation of gene expression and cell metabolism; and cytoskeletal rearrangements are highlighted. The PI3K pathway is implicated in human diseases including diabetes and cancer, and understanding the intricacies of this pathway may provide new avenues for therapuetic intervention.     

基于4D label-free技术的水稻成熟种子蛋白质组学研究

【目的】从蛋白水平揭示水稻种子成熟的分子基础，探究调控水稻种子成熟的关键蛋白和代谢通路。【方法】选用授粉后30 d的成熟水稻种子，利用4D label-free定量蛋白质组学进行质谱鉴定，通过生物信息学技术分析蛋白的亚细胞定位、结构域、GO注释和KEGG通路注释。【结果】总共鉴定了3 484个种子成熟期的蛋白，相对分子质量大多在10 000～100 000之间，主要分布于细胞质、细胞核、叶绿体、线粒体和质膜上；结构域主要涉及蛋白质翻译的RNA识别基序和蛋白磷酸化修饰的蛋白激酶结构域；GO分析表明，成熟种子的蛋白主要参与了细胞过程和代谢过程，主要涉及催化活性和结合等功能，大多分布在细胞、细胞组分、细胞器和细胞膜等部位；KEGG分析发现，蛋白主要富集在核糖体、内质网中的蛋白质加工、氧化磷酸化和糖酵解等途径，推测蛋白质的翻译、加工和能量代谢是水稻种子成熟期的主要分子事件；进一步鉴定了脱落酸(Abscisic acid,ABA)信号和吲哚乙酸(Indoleacetic acid,IAA)代谢的相关蛋白，同时也发现了NAC(NAM、ATAF1/2和CUC2)家族的转录因子。【结论】贮藏物质的积累...     

南海鸢乌贼微型群肌肉和性腺组织能量积累及其分配

利用组织能量密度测定技术和残差指标分析方法,分析了南海鸢乌贼微型群个体肌肉组织和性腺组织的能量积累及其分配规律的变化过程。结果显示,微型群个体的肌肉、性腺组织之间的能量密度存在显著性差异;除缠卵腺之外,其它组织的能量密度均随性腺发育变化显著。肌肉组织和性腺组织的组织能量积累均随性腺发育增加显著。同一性腺成熟度等级,肌肉组织的相对组织能量积累较高,性腺组织的相对组织能量积累相对较低。雌性个体性腺组织相对组织能量积累随着性腺发育增长显著,雄性个体性腺组织相对组织能量积累在Ⅰ期~Ⅴ期增长较快,在Ⅵ期~Ⅶ期趋于稳定。肌肉和性腺组织在性腺发育后期的质量特征较发育前期均显著改善,并且肌肉组织能量积累-胴长残差与性腺组织能量积累-胴长残差呈显著的正相关关系,表明性腺发育过程中的肌肉组织与性腺组织之间不存在能量交流。研究表明,南海鸢乌贼微型群个体的生殖能量倾向于外源性投入,肌肉和性腺组织的组织能量密度、组织能量积累和相对组织能量积累存在雌雄差异性。     

Regulation of phagosome maturation by signals from toll-like receptors

In higher metazoans, phagocytosis is essential in host defense against microbial pathogens and in clearance of apoptotic cells. Both microbial and apoptotic cells are delivered on a common route from phagosomes to lysosomes for degradation. Here, we found that activation of the Toll-like receptor (TLR) signaling pathway by bacteria, but not apoptotic cells, regulated phagocytosis at multiple steps including internalization and phagosome maturation. Phagocytosis of bacteria was impaired in the absence of TLR signaling. Two modes of phagosome maturation were observed, constitutive and inducible; their differential engagement depended on the ability of the cargo to trigger TLR signaling.     

Glia are essential for sensory organ function in C. elegans

Sensory organs are composed of neurons, which convert environmental stimuli to electrical signals, and glia-like cells, whose functions are not well understood. To decipher glial roles in sensory organs, we ablated the sheath glial cell of the major sensory organ of Caenorhabditis elegans. We found that glia-ablated animals exhibit profound sensory deficits and that glia provide activities that affect neuronal morphology, behavior generation, and neuronal uptake of lipophilic dyes. To understand the molecular bases of these activities, we identified 298 genes whose messenger RNAs are glia-enriched. One gene, fig-1, encodes a labile protein with conserved thrombospondin TSP1 domains. FIG-1 protein functions extracellularly, is essential for neuronal dye uptake, and also affects behavior. Our results suggest that glia are required for multiple aspects of sensory organ function.     

Autophagy and the nutritional signaling pathway

During their growth and development, animals adapt to tremendous changes in order to survive. These include responses to both environmental and physiological changes and autophagy is one of most important adaptive and regulatory mechanisms. Autophagy is defined as an autolytic process to clear damaged cellular organelles and recycle the nutrients via lysosomic degradation. The process of autophagy responds to special conditions such as nutrient withdrawal. Once autophagy is induced, phagophores form and then elongate and curve to form autophagosomes. Autophagosomes then engulf cargo, fuse with endosomes, and finally fuse with lysosomes for maturation. During the initiation process, the ATG1/ULK1 (unc-51-like kinase 1) and VPS34 (which encodes a class III phosphatidylinositol (PtdIns) 3-kinase) complexes are critical in recruitment and assembly of other complexes required for autophagy. The process of autophagy is regulated by autophagy related genes (ATGs). Amino acid and energy starvation mediate autophagy by activating mTORC1 (mammalian target of rapamycin) and AMP-activated protein kinase (AMPK). AMPK is the energy status sensor, the core nutrient signaling component and the metabolic kinase of cells. This review mainly focuses on the mechanism of autophagy regulated by nutrient signaling especially for the two important complexes, ULK1 and VPS34.     

Structural maturation of neural pathways in children and adolescents: in vivo study

Structural maturation of fiber tracts in the human brain, including an increase in the diameter and myelination of axons, may play a role in cognitive development during childhood and adolescence. A computational analysis of structural magnetic resonance images obtained in 111 children and adolescents revealed age-related increases in white matter density in fiber tracts constituting putative corticospinal and frontotemporal pathways. The maturation of the corticospinal tract was bilateral, whereas that of the frontotemporal pathway was found predominantly in the left (speech-dominant) hemisphere. These findings provide evidence for a gradual maturation, during late childhood and adolescence, of fiber pathways presumably supporting motor and speech functions.     

PI3Kgamma is a key regulator of inflammatory responses and cardiovascular homeostasis

Class I phosphoinositide 3-kinase (PI3K) signaling pathways regulate several important cellular functions, including cellular growth, division, survival, and movement. Class IB PI3K (also known as PI3Kgamma) links heterotrimeric GTP-binding protein-coupled receptors to these pathways. Activation of class IB PI3K results in the rapid synthesis of phosphatidylinositol-3,4,5-trisphosphate [PtdIns(3,4,5)P3] and its dephosphorylation product PtdIns(3,4)P2 in the plasma membrane. These two lipid messengers bind to pleckstrin homology domain-containing effectors that regulate a complex signaling web downstream of receptor activation. Characteristic features of this pathway are the regulation of protein kinases and the regulation of small guanosine triphosphatases that control cellular movement, adhesion, contraction, and secretion. Most of the ligands that activate class IB PI3K are involved in coordinating the body's response to injury and infection, and recent studies suggest that small molecule inhibitors of this enzyme may represent a novel class of anti-inflammatory therapeutic agents.     

Male crickets feed females to ensure complete sperm transfer

The spermatophore transferred by the male decorated cricket Gryllodes supplicans to the female during copulation includes a large gelatinous portion (spermatophylax), which the female removes and feeds on immediately after mating. Females usually removed and ate the smaller sperm-containing portion (ampulla) within 1 to 7 minutes after fully consuming or losing the spermatophylax. Complete sperm transfer requires that the ampulla remain attached for a minimum of 50 minutes; this corresponds to the average time at which females actually removed ampullae, 52.0 +/- 2.2 minutes after mating. These results indicate that nuptial feeding of the female cricket functions to deter females from removing the sperm ampulla before sperm transfer is complete.     

Extrusion of cells with inappropriate Dpp signaling from Drosophila wing disc epithelia

Decapentaplegic (Dpp) is a signaling molecule that controls growth and patterning of the developing Drosophila wing. Mutant cells lacking Dpp signal transduction have been shown to activate c-Jun amino-terminal kinase (JNK)-dependent apoptosis and to be lost from the wing disc epithelium. These observations have led to the hypothesis that Dpp promotes cell survival by preventing apoptosis. Here, we show that in the absence of JNK-dependent apoptosis, mutant cells lacking Dpp signal transduction can survive; however, they are still lost from the wing disc epithelium. This loss correlates with extensive cytoskeletal changes followed by basal epithelial extrusion. We propose that Dpp promotes cell survival within disc epithelia by affecting cytoskeletal organization.     

Larval testes of the tobacco budworm: a new source of insect ecdysteroids

Testes of last-instar larvae of the tobacco budworm release five times more ecdysteroid into incubation medium (judged by radioimmunoassay) in 2.5 hours than is found in testis homogenates. Incubation of testicular components indicates that the testis sheath may be the site of ecdysteroid synthesis. Fractionation of hemalymph, testis homogenate, and incubation medium by high-performance liquid chromatography produces a distinct ecdysteroid pattern in each case. Thus, released testis ecdysteroids are probably converted to other forms for use, sequestration, or general circulation. Their functions are unknown.     

基于MSP430单片机的生物质燃料常温成型机控制系统的设计

采用MSP430单片机为主控芯片,开发了一套生物质燃料常温成型机的自动控制系统,可将目前的液压手动阀控制作业方式转变为自动控制方式。介绍了以MSP430单片机为主控芯片的硬件电路图设计,以及基于该硬件的相关软件编程的方案,并通过调试电路板的测试,完成了该控制系统的制作。该系统在模拟环境下工作稳定,可实现预期功能。