铜对肉鸡肝细胞线粒体膜通透性及呼吸的影响

为进一步了解铜对生物体的生物学效应，选用硫酸铜作为铜源，向即时分离的肉鸡肝细胞线粒体培养液内加入终浓度分别为5、10、20μmol／L的铜（以铜计），孵育10min后，观察肝细胞线粒体膜通透性及呼吸的变化。结果显示，铜对线粒体膜通透性转换孔有较显著的影响，造成线粒体不同程度的肿胀，表现为线粒体悬液在540nm处的吸光值下降，且铜浓度越高，吸光值下降越明显，在孵盲6min后3种浓度的吸光值下降百分比差异显著（P〈0．05）。随着铜浓度的升高，线粒体呼吸逐渐减弱，RCR、P／O、OPR均显著降低（P〈0．05），这些变化可能是微量元素铜对生物机体产生毒害作用的本质原因之一。     

细胞质雄性不育水稻线粒体能量释放的热力学和动力学特征

高等植物细胞质雄性不育(Cytoplasmic male sterile, CMS)现象, 已在271种植物中发 现 。 根据少数几种较为深入的植物CMS研究, 人们认为这是一种可能由许多不同原因导致的 复 杂现象。 目前已有许多证据证明CMS与植物线粒体密切相关, 人们确信细胞质的不育 因子主要位于线粒体上, 不育系线粒体结构和功能均存在明显差异     

Induction of novel organelle DNA variation and transfer of resistance to frost and Verticillium wilt in Solanum tuberosum through somatic hybridization with 1EBN S. commersonii

Somatic hybridization can be used to induce genetic variability in plastidial and mitochondrial genomes, and transfer multiple uncloned genes across sexual barriers. Somatic hybrids were produced between a dihaploid clone of the common potato, S. tuberosum subsp. tuberosum, and the wild sexually incongruent diploid species S. commersonii. Fusion products were selected on the basis of callus growth and regeneration in vitro. Genome composition of putative somatic hybrids was determined by flow cytometric analysis of nuclear DNA content, RAPD analysis, and Southern analysis with probes specific to organellar DNA. All regenerated fusion products proved to be hybrids based on RAPD analysis. Seventy per cent of somatic hybrids were (near) tetraploids, 22% (near) hexaploids and 8%(near) octoploids. A high correlation was found between the nuclear DNA content determined by flow cytometry and the number of chloroplasts in stomata guard cell pairs. Somatic hybrids inherited the parental plastids in a random manner. On the contrary, they preferentially inherited the mitochondrial DNA fragments of S. tuberosum. The majority of them had a rearranged mitochondrial genome with fragments from both parents. Hybrids were highly vigorous and morphologically more similar to the cultivated than to the wild parent, produced tubers on long stolons under long photoperiod conditions, showed a high degree of flowering, but did not produce pollen. In addition, somatic hybrids were generally more resistant to frost and Verticillium wilt than the cultivated parent, indicating the introgression of relevant resistance genes from the wild species into the genetic background of S. tuberosum. This revised version was published online in July 2006 with corrections to the Cover Date.     

Substituted alpha-(phenylhydrazono)phenylacetonitrile derivatives. Part 2: Synthesis and biological activity of pro-pesticides

Pro-pesticides of alpha-(2,6-dichloro-4-trifluoromethylphenylhydrazono)-4-nitrophenylacetonitrile have been prepared and tested against mite and insect pests. Variations in potency and spectrum were observed depending on the choice of cleavable pro-moiety. Cleavage of the pro-moiety was demonstrated in one case by measuring the rate of increase in the uncoupling activity using a mitochondrial preparation. Irradiation experiments have demonstrated a rapid isomerisation of the planar Z isomer to the E isomer, which is reversible.     

低氧胁迫下不同品种凡纳滨对虾线粒体超微结构的比较

利用透射电镜技术比较研究了低氧胁迫对2个凡纳滨对虾品系(正大,A6410)的肌肉和鳃组织线粒体超微结构的影响。结果表明:常氧条件下,这2个凡纳滨对虾品系的肌肉和鳃中线粒体结构均匀,内外膜平滑完整,内嵴细长且分布均匀。低氧胁迫12 h后,正大品种肌肉线粒体膜扭曲变形,体积变大,嵴和基质明显减少,结构不完整且伴随着肌纤维疏松,肌丝断裂溶解;而A6410品种肌肉线粒体轻微肿胀,外膜和内膜局部发生变化,内嵴溶解,部分肌丝疏松断裂。正大品种鳃线粒体外膜扭曲变形,内嵴模糊且排列紊乱,髓样变形,呈现严重空泡化;A6410品种鳃线粒体嵴和基质部分减少,出现轻微空泡化现象。抗低氧性能较强的A6410肌肉和鳃线粒体受损程度明显轻于正大。不同组织对低氧胁迫的敏感性不同,且耐低氧性能与线粒体结构密切相关。     

钼对镉胁迫下山羊肝线粒体自由基代谢及肝Cyt-c基因mRNA表达的影响

选用27头健康波尔山羊随机分成3组,每组9头,选用钼酸铵[（NH4）6Mo7O24·4H2O]、氯化镉（CdCl2）作为试验钼源、镉源。对照组（试验Ⅰ组）口服相应剂量去离子水,试验Ⅱ、Ⅲ组灌服1mg Cd·kg^-1·BW,同时分别灌服15、45mg Mo·kg^-1·BW。试验50d,于0、25、50d每组剖杀3头山羊取肝组织样进行相关试验,观察钼镉对山羊肝线粒体自由基代谢及Cyt-c基因表达的影响。结果显示,与对照组比较,试验Ⅱ、Ⅲ组T-AOC、SOD活性下降（P〈0.05）,MDA、NO、NOS活性或含量及Cyt-c基因mRNA表达量上升（P〈0.05）,且随着试验时间的延长,T-AOC、SOD呈下降趋势（P〈0.05）;MDA、NO、NOS活性或含量及Cyt-c基因mRNA表达量呈上升趋势,试验钼镉组比较：当镉剂量一定时,试验钼镉组随着灌服钼剂量的升高,T-AOC活性呈下降趋势,MDA、NO、NOS活性或含量及Cyt-c基因mRNA表达量呈上升趋势。结果表明,钼可导致镉胁迫下山羊肝线粒体自由代谢紊乱,造成线粒体损伤同时诱导细胞凋亡相关基因Cyt-c表达上升,钼与镉呈协同效应。     

Development of large and small blastomeres from 2‐cell embryos produced in vitro in pigs

In the present study, we examined the development to blastocysts of large and small blastomeres from unevenly cleaved 2‐cell embryos (uneven 2‐cell embryos) in pigs. Proportion of blastocysts derived from large blastomeres (52.8 ± 6.4%) was significantly higher (P < 0.05) compared with small ones (32.1 ± 4.6%). However, there were no differences in total cell number, inner cell mass (ICM) cell number and ICM/total cells ratio between them. Of 53 sister blastomere pairs in the same embryos examined there were 12 pairs (22.6%) in which both blastomeres developed to blastocysts, 16 pairs (30.2%) in which only large blastomeres developed to blastocysts, and five pairs (9.4%) in which only small blastomeres developed to blastocysts. Relative total amount of active mitochondria in small blastomeres were lower (P < 0.05) than that of large blastomeres and blastomeres from evenly cleaved 2‐cell embryos. However, there was no difference in relative density of active mitochondria in these three types of blastomeres. In conclusion, blastocysts derived from small and large blastomeres in uneven 2‐cell embryos had comparable quality in terms of cell number, ICM number, ICM/total cell ratio and distribution of active mitochondria. The results suggest that these blastomeres may contribute multiple offspring production in pigs.     

喹乙醇致鸡中毒后线粒体膜的ATPase活性变化研究

将1日龄的艾维茵肉鸡随机分为空白对照组(Ⅰ组)和喹乙醇处理组(Ⅱ组)。2组动物以相同条件进行饲养,Ⅱ组按15mg/kg体重的剂量,将喹乙醇进行一次性口服,实验期42 d,每周进行一次采样,共采样6次。所采集的血液制备鸡肝线粒体膜(MiM),本实验以MiM上的Na -K -ATPase、Mg2 -ATPase和Ca2 -ATPase活性变化为检测指标。结果表明:Ⅱ组MiM的ATPase活性在整个实验过程中一直呈下降趋势。实验结果提示喹乙醇可以诱导生物膜ATPase活性的改变,导致线粒体膜功能障碍,使机体的解毒和排泄功能受损。     

白菜胞质雄性不育系及保持系叶片色素含量及其超微结构

以白菜胞质雄性不育系、原不育材料及其保持系为试材，比较了不同发育时期叶片色素含量及其超微结构的差异。结果表明，莲座期原不育材料色素含量极显低于新不育种质及保持系；而在苗期及抽薹期，色素含量差异均不显。各时期不育材料细胞器发育明显滞后于保持系。莲座期，原雄性不育材料叶绿体呈椭圆形，片层结构疏松，叶绿体数目及叶绿素含量明显低于新不育种质及保持系。保持系及新不育种质叶绿体发达，片层结构较多。同期保持系线粒体结构发达，内脊丰富，内含物充实；而不育系线粒体结构简单，内脊较少，线粒体的数目高于保持系。到抽薹期，无论叶绿体还是线粒体都呈退化状态，叶绿体内累积淀粉粒，线粒体内脊减少，不育系线粒体严重空泡化。     

小花棘豆溶血毒素对兔脑神经细胞线粒体的影响

本研究首次证明小花棘豆(Oxytropis glabra DC)溶血毒素对兔脑神经细胞线粒体的结构和功能有显著影响,即:抑制线粒体细胞色素氧化酶和琥珀酸脱氢酶活力,降低氧化磷酸化效率(ADP/O)、呼吸控制率(RCR),使呼吸激活迟缓,并引起线粒体超微结构的异常变化。该毒素还引起线粒体中至少两种分子量不同的蛋白质(MW=63000和55000)的裂解,其性质尚待进一步查明。