Regeneration of fertile transgenic indica (group 1) rice plants following microprojectile transformation of embryogenic suspension culture cells

Regenerable embryogenic suspensions of elite Indica (group 1) rice varieties IR24, IR64, IR72 and an advanced Indica rice breeding line IR57311-95-2-3 were established within 6–8 weeks from 3–4 week old calli derived from mature seeds. Transgenic rice plants were obtained by introducing a plasmid carrying genes encoding hygromycin phosphotransferase (hph, conferring resistance to hygromycin B) and ß-glucuronidase (uidA), both driven by the CaMV 35S promoter, via particle bombardment of embryogenic suspensions. The effect of osmotic conditioning on transformation was evaluated. Regenerated plants were resistant to hygromycin B and expressed the uidA (GUS) gene. The growth of mother plants (R₀) was normal and seeds were produced. Southern blot analysis of R₀ and R₁ plants showed that hygromycin resistant plants contained intact hph genes that were inherited in a Mendelian fashion. A protocol for a simple, efficient, repeatable, genotype- and environment-independent Indica rice transformation system is described.Abbreviations 2,4-D 2,4-dichlorophenoxy acetic acid - NAA -naphthalene acetic acid - kb kilobase - GUS ß-glucuronidase - hph hygromycin B phosphotransferase     

腺苷三磷酸和环腺苷单磷酸对丝状真菌纤维素酶合成的调节

以虫荧光素酶法检验了四株丝状真菌在葡萄糖—无机盐液体培养过程中的胞内ATP含量。结果表明,只有当胞内ATP浓度低于10~(-S)mg/ml时,真菌才开始合成胞外纤维素酶(FPA)。以不同浓度的各种碳源培养时,菌体胞内ATP含量只要超过10~(-1)mg/ml,FPA的合成即发生阻遏。菌体胞内ATP含量与FPA合成呈显著负相关。以高效液相色谱(HPLC)法检测了菌体培养液中的cAMP含量。在非阻遏条件下,外源cAMP可以提高FPA的合成水平。但外源cAMP不能解除已经发生的酶合成阻遏。菌体ATP和cAMP水平是调节真菌纤维素酶合成的重要因子。     

L-山梨糖提高木霉纤维素酶合成速率机制的研究

在0.5％葡萄糖-Mandels盐培养液中添加终浓度为0.5％的L-山梨糖,可使里斯木霉(Trichoderma reesei C 30)和拟康氏木霉(Trichoderma pseudokoningii S38)的内切和外切β-1,4葡聚糖酶合成速率在培养的2天内提高4倍。与此同时β-葡萄糖苷酶的合成没有明显变化。L-山梨糖能明显抑制菌丝生长,但对葡萄糖的吸收没有影响,对菌丝分泌纤维素酶的机制影响不大。其对酶合成的促进可能主要是通过降低了菌丝体的生长速率。     

人粒细胞集落刺激因子（hG－CSF）cDNA3′－UTR对其表达的影响

利用人粒细胞集落刺激因子（ｈＧ－ＣＳＦ）ｃＤＮＡ３′端非翻译区（３′－ＵＴＲ）中存在的ＤｒａⅠ酶切位点,通过部分酶切与完全酶切,删除３′－ＵＴＲ不同长度,构建了四种ｈＧ－ＣＳＦｃＤＮＡ瞬时重组表达质粒。转染ＣＯＳ－７细胞后,生物活性测定结果提示,ｈＧ－ＣＳＦｃＤＮＡ３′－ＵＴＲ对其表达起负调控作用,其关键性序列位于紧接终止密码子ＴＧＡ下游的６５ｂｐ范围内,３′－ＵＴＲ对ｈＧ－ＣＳＦｃＤＮＡ表达的影响与转录水平的差别有一定关系。     

细胞色素c在氨基酸及二肽修饰金电极上的电化学反应

系统地研究了细胞色素ｃ在多种氨基酸和多肽修饰电极上的电化学反应。并对影响加速细胞色素ｃ电化学反应的因素进行了讨论。     

骨骼肌M蛋白抗血清的制备及正常人骨骼肌M蛋白的免疫电镜定位

分别制备了兔抗人Ｍ蛋白（Ｂ成分）抗血清和兔抗人Ｃ成分［１］抗血清。用蛋白Ａ－胶体金作标记物,对经ＬｏｗｉｃｒｙｌＫ４Ｍ低温包埋的人骨骼肌超薄切片中Ｍ蛋白和分子量１４００００的Ｃ成分进行免疫电镜定位。发现Ｍ蛋白分布于整个Ｍ线,而Ｃ成分虽然也集中于Ｍ线以内,但主要分布于Ｍ线内的边缘区域。     

Immunolocalization of tenascin and cellular fibronectins in diverse glomerulopathies

Frozen samples of minimal change glomerulopathy (MCG), and of membranous, segmental and diffuse lupus glomerulonephritis (MGN, SGN, DLGN) were studied to assess the distribution of tenascin (Ten), and the extradomains A and B (EDA-and EDB-) and oncofetal (Onc-) isoforms of cellular fibronectin (cFn). Cryosections were immunostained by the ABC method with specific monoclonal antibodies. In MCG, mesangial Ten and EDA-cFn reactions were increased. In MGN, mesangial Ten and EDA-cFn staining was enhanced except in segmental scars; convincing reactions were seen in cases with membranous transformation; spikes stained strongly. In SGN, variably intense staining for Ten and all cFn isoforms was seen in glomerular necrosis, proliferation and crescents; parietal epithelium EDA-cFn staining was noted. In DLGN, strong and extensive mesangial Ten and EDA-cFn staining was seen as were focal EDB-and Onc-cFn reactions. Parietal cells with and without crescents stained variably with all Mabs. Obsolete glomeruli were unreactive save for rare periglomerular Ten rims. Interstitial inflammation and fibrosis in MGN, SGN and DLGN had moderate to strong Ten and EDA-cFn staining with rare traces of EDB-and Onc-cFn. We conclude that enhanced Ten and EDA-cFn is a potentially reversible response to glomerular injury whereas the expression of EDB-and Onc-cFn apparently result from necrosis and/or cellular proliferation which lead to scarring. And, while mesangial cells are the major source of these molecules, epithelial cells might also partake in their synthesis.     

四种主要大豆食叶害虫种群空间分布型及其应用研究

通过分层随机与连片调查获得114个样本．利用微机分别对豆天蛾卵和豆天蛾．银纹夜蛾．棉铃虫．豆灰蝶及混合种群的幼虫．进行了4种频次分布型检验和6项聚集度指标的测定．结果表明．上述害虫在豆田内均属零集分布．中分析了聚集原因．提出了“Z”字型10样点,每样点以1／3m双行为单位的抽样方法．确立了在两种允许误差下的抽样数量．进行了序贯抽样分析。