Identification of genes showing differential expression profile associated with growth rate in skeletal muscle tissue of Landrace weanling pig

Suppression subtractive hybridization was used to identify genes showing differential expression profile associated with growth rate in skeletal muscle tissue of Landrace weanling pig. Two subtracted cDNA populations were generated from musculus longissimus muscle tissues of selected pigs with extreme expected breeding values at the age of 100 kg. Three upregulated genes (EEF1A2, TSG101 and TTN) and six downregulated genes (ATP5B, ATP5C1, COQ3, HADHA, MYH1 and MYH7) in pig with genetic propensity for higher growth rate were identified by sequence analysis of 12 differentially expressed clones selected by differential screening following the generation of the subtracted cDNA population. Real-time PCR analysis confirmed difference in expression profiles of the identified genes in musculus longissimus muscle tissues between the two Landrace weanling pig groups with divergent genetic propensity for growth rate. Further, differential expression of the identified genes except for the TTN was validated by Western blot analysis. Additionally, the eight genes other than the ATP5C1 co-localized with the same chromosomal positions as QTLs that have been previously identified for growth rate traits. Finally, the changes of expression predicted from gene function suggested association of upregulation of expression of the EEF1A2, TSG101 and TTN genes and downregulation of the ATP5B, ATP5C1, COQ3, HADHA, MYH1 and MYH7 gene expression with increased growth rate. The identified genes will provide an important insight in understanding of the molecular mechanism underlying growth rate in Landrace pig breed.     

大鼠背外侧索中各类上行纤维的电生理学特征

在大鼠胸髓下段,用分离纤维细束法观察背外侧索(dorsolateral funiculus,DLF)中各类上行纤维的电生理学特征。在记录的251个单位中,144个主要接受A_β类纤维输入的单位对触毛和/或轻压皮肤反应,26个伤害性单位和毛压-伤害性会聚单位接受A_δ和C纤维的传入;这两类纤维主要沿DLF的中、浅层上行,且具有明显的会聚特点;提示其中部分单位可能属于脊颈束(spinocervicaltract,SCT)。在DLF的深、中层分离到61个对关节运动敏感的单位,它们可能属于脊髓小脑背束(dorsal spinocerebellar tract,DSST)。另有20个对各类自然刺激均无反应的自发单位。在DLF的浅层近背根处,还记录到38条来自对侧的交叉上行纤维,它们与同侧的非交叉上行纤维相混杂,其生理学特性与同侧上行纤维相似,本文结果提供了大鼠DLF中存在部分交叉上行纤维的生理学证据。     

Effect of Methyl Jasmonate on the Germination and the Degradation of Storage Reserve in Rice Seed

The effects of methyl jasmonate (MeJA, Nippon Zeon Co., Ltd, Tokyo, Japan) on germination and the degradation of storage reserve in rice （Oryza sativa L.） seeds were studied. There were dual effects of MeJA on seed germination and seedling growth of rice, low concentration of MeJA promoted germination and seedling growth whereas high concentration of MeJA inhibited germination and seedling growth. The optimal concentration of promotion was 5×10-7 mol/L. The acid phosphatase activity, α-amylase activity, degradation of starch and salt-soluble proteins were affected same as germination by MeJA. MeJA inhibited the degradation of glutelins, the higher the concentration, the higher the extent of inhibition above 5×10-7 mol/L.The results showed that either promotion or inhibition of germination by MeJA was very close to the effect on the activity of α-amylase. The mechanisms between abscisic acid and MeJA affection on seed germination and seedling growth were compared.     

贝类精子质量检测与评价方法研究Ⅰ：染色法检测马氏珠母贝精子的存活率的研究1

用曙红 Y、台盼蓝染料对马氏珠母贝(Pinctada martensii)精子进行染色,通过对不同制片方法、不同的染色时间和不同染料浓度的染色效果进行比较,筛选出可通过染色特征来检测精子死活及活精率的适宜方法,结果显示：(1)经染色后,死、活精子呈现出明显不同的特征：活精子均不着色,头部呈梨形、无色透明状;死精子着红色(曙红Y染色)或蓝色(台盼蓝染色),体积变大,头部近圆形。(2)曙红Y、台盼蓝最适染色浓度分别为0.04%和0.2%;最佳染色时间均为15min。(3)检测到的精子死亡率即实测精子死亡率,与“理论死亡率”之间有明显的相关性,相关系数为R=0.99(P＜0.01),并且两种染色法的观察结果一致,表明这些检测结果客观可信;(4)染料对活精子毒性的检测显示,染色45min内,精子死亡率无显著性增加(P＞0.05),说明在该时间范围内,染液对精子的毒性较小,精子存活率的检测结果稳定可靠。这些研究表明,曙红 Y、台盼蓝两种染色法准确灵敏,均适宜用于马氏珠母贝精子质量的检测与评价。     

动物肌球蛋白碱性轻链研究进展

肌球蛋白碱性轻链是肌球蛋白的组成成分之一,作为结构和调节蛋白在肌纤维的发生分化、肌肉运动和代谢等过程中发挥重要生理功能。简要综述肌球蛋白碱性轻链亚型的分析、碱性轻链基因的数量和分布、碱性轻链发育性表达等,为肌肉发育生物学研究提供参考。     

基于Solexa高通量测序的黄曲条跳甲转录组学研究

黄曲条跳甲Phyllotreta striolata (Fabricius) 是十字花科蔬菜的重要害虫。为深入了解其遗传信息, 本研究应用新一代高通量测序技术Illumina’s Solexa平台对黄曲条跳甲成虫的转录组进行测序, 并结合SOAPdenovo拼接聚类等分析软件, 获取大量的EST和挖掘功能基因。本文最终获得了4 924条序列重叠群（contig）, 其中包含2 209种与黑腹果蝇Drosophila melanogaster蛋白基因具直系同源的独立基因（unigene）和610种黄曲条跳甲物种特有的unigene。结合Gene Ontology （GO）数据库进行分析, 发现大部分的unigene具结合能力（binding capability）和催化活性（catalytic activity）; 上百种unigene可聚类于生物学过程分类中的配子发生、 生殖腺发育和交配行为等重要功能。另外, 结合KEGG Pathway数据库分析发现, 共有363种unigene参与或涉及了40种代谢路径, 其中生物钟调控路径和植物次生代谢物路径等相关基因的发现, 有助于深入研究黄曲条跳甲行为发生的内在机理。Solexa高通量测序技术作为昆虫功能基因组研究的重要手段, 为发掘黄曲条跳甲功能基因发挥了重要作用, 也为在分子水平上研发黄曲条跳甲的防治新策略提供了更翔实的基因信息。     

绿豆下胚轴质膜微囊的提取和H+-ATPase 活性研究

以两相法提取纯化绿豆下胚轴质膜微囊,材料与两相体系重量之比为32∶8时,一次洗膜就可以得到纯度较高的质膜微囊。提取缓冲液中牛血清白蛋白的浓度对质膜H+-ATPase的潜在活性有影响。质膜H+-ATPase水解活性依赖于Mg2+,Ca2+对酶活性有明显的促进作用。壳梭孢素（fusicoccin, FC）对酶有明显的刺激作用,活体条件最大刺激达到72％,而离体条件下刺激为30％。     

茉莉酸甲酯对水稻种子萌发和贮藏物质降解的影响

茉莉酸甲酯 (methyljasmonate ,MeJA)对水稻 (OryzasativaL .)种子萌发及幼苗生长的作用表现出“双重性”效应 ,低浓度促进种子萌发和幼苗生长 ,最适浓度为 5× 10 -7mol/L ,高浓度作用相反。MeJA对水稻萌发胚乳酸性磷酸酶、α_淀粉酶、淀粉和盐溶蛋白降解作用也如此 ,但它抑制谷蛋白降解。实验结果表明 ,MeJA促进和抑制水稻种子萌发都与α_淀粉酶活性有关。讨论了MeJA对种子萌发作用与ABA作用的异同     

根缘细胞的发生和生物学作用

植物根尖每天都要代谢大量的根缘细胞,这些根缘细胞能改变土壤的生化特性,平衡根际环境,保护植物的根尖免受外界胁迫如铝毒、线虫和病菌的侵染等伤害。通过对根缘细胞数量和特性的调节可协调植物与外界环境的互作。本文对根缘细胞的发生、根尖的防御机制及发生的内在原因等作了综述。