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1.
原生质体技术选育桃红侧耳优良菌株   总被引:6,自引:0,他引:6  
研究了桃红侧耳原生质体的制备及再生,并进行了原生质体再生株的筛选工作。实验表明,培养5天的桃红侧耳菌丝体30℃酶解3h原生质体数目可达8.4×107/mL。原生质体再生率在1号再生培养基上最高,为6.9%。再生菌株经筛选后,得到长速显著快于出发菌株的优良菌株H120和H247。经F3代栽培实验证明:H120和H247的生物学效率明显优于出发菌株,且差异极显著。酯酶同工酶分析表明:H120和H247酶谱均发生了变化。  相似文献   
2.

Background

To cope with harsh environments, crustaceans such as Artemia produce diapause gastrula embryos (cysts) with suppressed metabolism. Metabolism and development resume during post-diapause development, but the mechanism behind these cellular events remains largely unknown.

Principal Finding

Our study investigated the role of prohibitin 1 (PHB1) in metabolic reinitiation during post-diapause development. We found that PHB1 was developmentally regulated via changes in phosphorylation status and localization. Results from RNA interference experiments demonstrated PHB1 to be critical for mitochondrial maturation and yolk degradation during development. In addition, PHB1 was present in yolk platelets, and it underwent ubiquitin-mediated degradation during the proteolysis of yolk protein.

Conclusions/Significance

PHB1 has an indispensable role in coordinating mitochondrial maturation and yolk platelet degradation during development in Artemia. This novel function of PHB1 provides new clues to comprehend the roles of PHB1 in metabolism and development.  相似文献   
3.

Background

In the clinic, variations in circadian rhythm are evident in patients with cardiovascular disease, and the risk of cardiovascular events increases when rhythms are disrupted. In this study, we focused on the role of the circadian gene period2 (per2) in mobilization and function of endothelial progenitor cells (EPCs) in vitro and in vivo after myocardial infarction (MI) in mice.

Methods and Results

MI was produced by surgical ligation of the left anterior descending coronary artery in mice with and without per2 deficiency. Trans-thoracic echocardiography was used to evaluate cardiac function in mice. Per2−/− mice with MI showed decreased cardiac function and increased infarct size. The number of CD34+ cells and capillary density were decreased in the myocardium of per2−/− mice on immunohistochemistry. Flow cytometry revealed decreased number of circulating EPCs in per2−/− mice after MI. In vitro, per2−/− EPCs showed decreased migration and tube formation capacity under hypoxia. Western blot analysis revealed inhibited activation of extracellular signal-regulated kinase and Akt signaling in the bone marrow of per2−/− mice and inhibited PI3K/Akt expression in per2−/− EPCs under hypoxia.

Conclusions

Per2 modulates EPC mobilization and function after MI, which is important to recovery after MI in mice.  相似文献   
4.
中华蓑藓(Macromitrium cavaleriei Card.&Thér.)的形态变异强烈,为了解形态变异是否具有遗传学背景,本研究以采自浙南凤阳山、浙中金华北山、浙西北的天目山和江西庐山4个种群的中华蓑藓为材料,运用随机扩增多态性DNA(RAPD)探讨了中华蓑藓的遗传多样性。从100条随机引物中筛选出了15条有效引物,利用它们共获得183个条带,其中多态性条带占79·69%,中华蓑藓各种群间的Dice遗传距离为0·0732~0·1514。POPGENE32软件分析得到种的Nei基因多样性指数(H)为0·3378,Shannon指数(I)为0·5126,遗传分化系数(Gst)为0·1670;基因流(Nm)为2·4947;种群内遗传多样性指数为0·4055,占种群总的遗传多样性的79·11%,反映出研究区域内的中华蓑藓遗传变异大多数存在于种群内,中华蓑藓形态变异并没有多少遗传背景,很可能是生态环境因素引起的可塑性变异。聚类分析表明,中华蓑藓种群遗传距离与地理距离之间无直接相关关系,遗传多样性水平与物种特性和所处不同群落有关。虽然4个种群内的形态变异丰富,但是属于同一物种的范围。  相似文献   
5.
由于草本植物持续上侵长白山灌木苔原,形成了强烈的灌草群落种间竞争。本研究以牛皮杜鹃-小叶章群落(Comm.Rhododendron aureum-Deyeuxia purpurea)为对象,根据小叶章的入侵程度设置4种盖度差异显著的样方(无、轻度、中度、重度入侵),并设3个施氮水平(自然状态、添加11.8 kgN·hm-2·a-1及添加23.6 kgN·hm-2·a-1),进行原位氮沉降模拟实验,监测灌木牛皮杜鹃和草本植物小叶章光合特性的差异和变化趋势,研究小叶章入侵苔原带的内在生理机制。结果显示:(1)小叶章净光合速率大于牛皮杜鹃,小叶章盖度越高、其叶绿素含量越高,而牛皮杜鹃叶绿素含量降低,随着小叶章入侵程度的增加,其净光合速率增强;(2)施氮可以提高牛皮杜鹃和小叶章的叶绿素含量和净光合速率,促进植物生长,但小叶章的增幅更大,从而增强了小叶章的竞争优势;(3)施氮和小叶章入侵具有复合作用,小叶章盖度越大,对其施氮导致小叶章净光合速率与叶绿素含量的增幅越大,而牛皮杜鹃的增幅减小。所以小叶章的成功入侵可能与其具有较高的净光合速率有关,并且施氮有利于提高小叶章的净光合速率,随着氮沉降的继续增加,更有利于小叶章的生长并提高其竞争力。  相似文献   
6.
Successful pregnancy in placental mammals substantially depends on the establishment of maternal immune tolerance to the semi-allogenic fetus. Disorders in this process are tightly associated with adverse pregnancy outcomes including recurrent miscarriage(RM). However, an indepth understanding of the systematic and decidual immune environment in RM remains largely lacking. In this study, we utilized single-cell RNA-sequencing(sc RNA-seq) to comparably analyze the cellular and molecular signatures of decidual and peripheral leukocytes in normal and unexplained RM pregnancies at the early stage of gestation. Integrative analysis identifies 22 distinct cell clusters in total, and a dramatic difference in leukocyte subsets and molecular properties in RM cases is revealed. Specifically, the cytotoxic properties of CD8+effector T cells, nature killer(NK), and mucosal-associated invariant T(MAIT) cells in peripheral blood indicates apparently enhanced pro-inflammatory status, and the population proportions and ligand–receptor interactions of the decidual leukocyte subsets demonstrate preferential immune activation in RM patients.The molecular features, spatial distribution, and the developmental trajectories of five decidual NK(d NK) subsets have been elaborately illustrated. In RM patients, a d NK subset that supports embryonic growth is diminished in proportion, while the ratio of another d NK subset with cyto-toxic and immune-active signature is significantly increased. Notably, a unique pro-inflammatory CD56+CD16+d NK subset substantially accumulates in RM decidua. These findings reveal a comprehensive cellular and molecular atlas of decidual and peripheral leukocytes in human early pregnancy and provide an in-depth insight into the immune pathogenesis for early pregnancy loss.  相似文献   
7.
由枸杞髓部组织诱导出胚性愈伤组织,并由此愈伤组织建立起稳定的细胞悬浮系。从悬浮细胞游离的原生质体在改良KM培养基(1.5 mg/L 6_BA,0.5 mg/L NAA和0.5 mg/L 2,4_D)中进行液体浅层培养,3~4 d后出现第一次分裂,第7 d统计分裂频率为50.3%,15 d左右可形成细胞团,3~4周后形成肉眼可见的愈伤组织,愈伤组织植板率为1.25%。将细胞团转移到液体分化培养基(MS+6_BA 1.5 mg/L+2,4_D 0.2 mg/L) 8~10 d可形成大量胚状体,及时将胚性愈伤组织块转移到固体分化培养基上(MS+6_BA 0.2 mg/L),可形成大量绿芽,分化率54.17%。绿芽在生根培养基(MS+NAA 0.2 mg/L)可形成完整植株,移栽后成活良好。  相似文献   
8.
9.
记述花萤亚科Cantharinae 2中国新纪录属、种,即柯氏太平花萤Pacificanthia knirschi (Pic,1929)和乌苏里足花萤Podistra (Pseudoabsidia) ussurica (Wittmer,1979),提供了属征与种的再描记、整体照片、雄性外生殖器特征图和分布图。  相似文献   
10.
利用外源信号物质氟草敏(norflurazon)和2,6-二甲氧基对苯醌(2,6-DMBQ)分别诱导肉苁蓉种子萌发与吸器形成,研究它们在此过程中对内源激素脱落酸(ABA)、赤霉素(GA3)、吲哚乙酸(IAA)、玉米素核苷(ZR)水平变化的影响。结果表明:在诱导肉苁蓉种子萌发时,经norflurazon处理0~168h后,种子中ABA水平呈现显著降低的变化趋势,GA3、IAA、ZR水平呈现显著升高的变化趋势。在诱导肉苁蓉种子萌发体吸器形成时,经2,6-DMBQ处理0~72h后,肉苁蓉种子萌发体ABA水平变化不显著,GA3、IAA、ZR水平均呈现显著升高的变化趋势。表明在肉苁蓉种子萌发与吸器形成中外源信号物质nor-flurazon和2,6-DMBQ能影响内源激素水平的变化。  相似文献   
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