拟南芥角果发育和开裂的调控机制及在油菜育种中的应用

十字花科芸苔属甘蓝型油菜(Brassica napus)在角果发育成熟过程中,因角果开裂种子散落引起产量损失最低达20%左右,最高可达50%左右。模式植物拟南芥在角果形态和开裂机制方面与甘蓝型油菜具有相似性,角果开裂主要与果瓣、胎座框和果瓣边缘层的细胞发育有关。通过对拟南芥角果发育期间基因对果瓣、胎座框和果瓣边缘层的识别和发育进行综述,明确了拟南芥角果发育和开裂的基因调控机制,提出了从模式植物到大田作物甘蓝型油菜抗裂角育种的新策略。     

应用小孢子和花药培养技术筛选油菜抗菌核病材料

油菜菌核病是世界油菜产区的重要病害之一,迄今尚未找到有效的控制方法.现有油菜品种中未见有能抗病的,双低油菜育种的成功诚然推动了油菜品质育种工作,但优质品种的抗菌核病能力下降.培育抗菌核病的优质油菜是世界性的研究难题.我们以探索创造油菜抗菌核病新种质的新途径为目的,开展了采用油菜小孢子/花药培养,平阳霉素诱变和草酸胁迫相结合的方法,诱导和筛选抗病变异体的研究.     

油菜抗裂果性研究简述

本文简述了油菜易裂果性的危害、抗裂果性研究的意义及国内外研究现状和进展;也介绍了我国现有的主要抗裂果性油菜资源,并提出国内应开展油菜抗裂果性遗传机理研究和转基因研究的建议。     

甘蓝型油菜EMS诱变及多分枝和长角突变体分析

油菜是世界上最重要的油料作物之一,同时也是我国食用油和饲用蛋白质的主要来源。采用0.8%甲基磺酸乙酯(ethyl methane sulfonate,EMS)溶液处理甘蓝型油菜玻里马胞质雄性不育系(pol cms)的保持系2B种子,从田间M_2诱变群体中筛选获得1 495个变异株,包括叶色、叶型、早花、株高和株型、雄性不育、裂蕾、花瓣形状和颜色、多分枝和长角等变异性状,占M_2诱变群体的7.4%。对多分枝和长角突变材料的农艺性状进行观察和统计分析,结果表明多分枝突变材料平均一次有效分枝比野生型多1.03倍,单株产量增加41.48%;长角突变材料角果长度为野生型的1.69倍,但果粒数无差异,单株产量提高49.66%。研究结果为今后进一步发掘这些突变性状相关基因,并应用于油菜品种改良奠定了基础。     

油菜抗裂果性研究简述

本简述了油菜易裂果性的危害、抗裂果性研究的意义及国内外研究现状和进展；也介绍了我国现有的主要抗裂果性油菜资源，并提出国内应开展油菜抗裂果性遗传机理研究和转基因研究的建议。     

转基因抗除草剂油菜对近缘作物的基因漂移

以转基因抗除草剂油菜 Q3和 HCN- 19为花粉供体材料 ,油菜近缘作物为花粉受体材料 ,在自然授粉条件下研究甘蓝型油菜与芸薹属近缘作物间的基因漂移频率。结果表明 ,油菜对芸薹属 6个种甘蓝、黑芥、埃芥、芥菜型油菜、白菜型油菜和甘蓝型油菜的基因漂移率分别为 0、0 .0 2 4 %～ 0 .2 4 3%、 0 .0 2 8%～ 0 .0 92 %、 0 .10 9%～ 0 .95 1%、 0 .4 79%～ 0 .879%、 1.2 5 2 %～2 .191%。且基因漂移频率受多种因素影响 ,其中与杂交亲和性、花期同步率、种植面积等高度相关。通过花粉将抗除草剂基因漂移给近缘作物 ,油菜是需要特别关注的作物     

基于SLAF-seq技术鉴定甘蓝型油菜叶缘裂刻性状候选基因

叶缘裂刻性状是甘蓝型油菜遗传育种的理想形态标记。叶缘裂刻性状变异材料的创建对丰富甘蓝型油菜叶片形态和优良品种改良至关重要。本研究以甘蓝型油菜常规品种中双11和甘蓝型油菜叶缘裂刻新品系Y176为亲本(通过甘蓝型油菜与菜远缘杂交获得),从F2群体中分别挑选出叶缘裂刻和正常叶形的植株各50株,构建了两个极端性状混池DNA文库,借助SLAF-seq-BSA技术,挖掘甘蓝型油菜叶缘裂刻性状相关候选基因。共开发出177941个SLAF标签,通过分析SLAF标签的多态性,共获得150168个SNP,其中亲本间共获得128200个SNP。对ED方法和SNP-index方法得到的关联区域进行综合分析,获得1个与目标性状紧密关联的候选区域,位于甘蓝型油菜A10染色体上的14528149～17353693区域,总长度为2.83 Mb,约有666个编码基因。与前人研究定位在同一染色体上,但本研究定位的区间与前人研究不同,说明本研究存在控制叶缘裂刻新基因的可能性大。并对该区域内基因进行功能注释,其中666个注释到NR数据库;517个注释到SwissProt数据库;587个注释到GO数据库;151个注释到KEGG通路;258个注释到COG数据库,对候选基因进行注释有助于进一步分离相关基因。     

人工合成甘蓝型油菜特长角变异系的选育

用中国西藏东部采集的1个白菜型油菜地方品种与云南甘蓝类蔬菜白花芥蓝远缘杂交,人工合成了甘蓝型油菜新材料,从杂种后代中通过系统选育,获得了1个特长角变异系,其主花序中部角果平均长度20cm左右,果身长16～18cm,果喙长3cm左右.从中获得的极端最长角果达31.5cm,果身长26.1cm,果喙长5.4cm.这是迄今芸苔属植物中很少见到的长角果油菜材料.该材料的平均角果长度大约为普通甘蓝型油菜的3倍左右,遗传已基本稳定,定名为川农特长角.本文报导其选育经过和主要特征特性,并对其育种和研究利用价值作了简要分析.     

转基因抗除草剂油菜对十字花科杂草的基因漂移

以转基因抗除草剂油菜Q3为花粉供体材料,油菜远缘杂草为花粉受体材料,在自然传粉和人工辅助授粉条件下研究甘蓝型油菜与十字花科杂草间的基因漂移频率。结果表明,以转基因油菜为父本,十字花科杂草荠菜、碎米荠、播娘蒿、诸葛菜、风花菜、遏蓝菜和菜为母本,杂交高度不亲和,基因漂移率为0 % ,无生态风险,但对野芥菜的基因漂移率高达0 .885 %。野芥菜是我国大部分地区的常见杂草,种类繁多,分布范围广,大面积种植转基因抗除草剂油菜对野生芥菜的基因污染应引起高度重视。     

转基因抗草甘膦油菜的检测方法

目的:建立检测田间转基因抗草甘膦油菜的方法。方法:用CTAB法提取DNA,经PCR分别扩增内参基因BnACCg8,及抗草甘膦外源基因CP4-EPSPS、FMV 35S启动子和E9 3’终止子等4种基因的片段,以琼脂糖凝胶电泳对扩增产物进行分析比对。结果:抗草甘膦油菜中分别扩增出与外源基因FMV 35S启动子、E9 3’终止子和CP4-EPSPS大小一致的片段。结论:该方法能有效地用于转基因抗草甘膦油菜的检测。     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。