Nicotiana ovule extracts in duce nuclear reconstitution of demembranated Xenopus sperm in cell-free system

s Nicotiana tabaccum ovule extracts induced nuclear reconstitution of demembranated Xenopus leavis sperm in a ceil-free system. Demembranated Xenopus sperm began to swell after 15 rmin of incubation with Nicotiana ovulde extracts. Accompanying the process of incubation,Xenopus sperm decondensed and their shapes changed gradually from long and ellipse to round. The completely decondensed chromatin was surrounded with membrane structure, which was a mixture envelope of a double membrane and a single membrane. Nucleosome assembly was verified by means of micrococcal nuclease digestion to reconstituted nuclei and DNA electrophoresis. Nicotiana ovule extracts supplied one more experimental model and system.The new system could promote powerfully the research on mechanisms of cell division and cell cycle regulation.     

Nicotiana ovule extracts induce nuclear reconstitution of demembranated Xenopus sperm in cell-free system

Nicotiana tabaccum ovule extracts induced nuclear reconstitution of demembranated Xenopus leavis sperm in a cell-free system. Demembranated Xenopus sperm began to swell after 15 min of incubation with Nicotiana ovule extracts. Accompanying the process of incubation, Xenopus sperm decondensed and their shapes changed gradually from long and ellipse to round. The completely decondensed chromatin was surrounded with membrane structure, which was a mixture envelope of a double membrane and a single membrane. Nucleosome assembly was verified by means of micrococcal nuclease digestion to reconstituted nuclei and DNA electrophoresis. Nicotiana ovule extracts supplied one more experimental model and system. The new system could promote powerfully the research on mechanisms of cell division and cell cycle regulation.     

Coat protein gene and 3′ non-coding region of tobacco mosaic virus and tomato mosaic virus are associated with viral pathogenesis in Nicotiana tabacum

The camellia isolate of tomato mosaic virus (ToMV-TL) can induce local necrotic lesions on the inoculated leaves in Nicotiana tabacum, whereas the broad bean isolate of tobacco mosaic virus (TMV-B) produces the mosaic symptom on systemic leaves. To examine viral determinant for differential infection phenotype in N. tabacum, the coat protein gene and the 3′ non-coding region of TMV was replaced with that of ToMV, the chimeric virus induced similar local necrotic lesions to that induced by ToMV. The results indicate that the coat protein gene and the 3′ non-coding region of TMV and ToMV influence the virus-induced pathogenesis in N. tabacum.     

烟草叶片腺毛的研究

对烟草K326再生植株叶片腺毛的密度、发生及形态结构的研究表明，烟草幼叶腺毛密度较大，随叶片的发育而逐渐降低，烟草腺毛分为长柄腺毛与短柄腺毛两种类型，都由原始表皮细胞经过不同的分裂形式而最终发育成为腺毛，腺毛分泌细胞中有多糖类物质存在。     

不同土壤对心叶烟和三生烟种子萌发率的影响

测定了四种不同土壤的基本理化性质,并分别用其培育心叶烟和三生烟种子,统计两种烟草种子在四种土壤中的萌发率.结果表明:两品种烟草种子萌发率在育烟基质与其他3种土壤间有极显著差异(p<0.01),而在两烟草品种间差异不显著.     

砷胁迫对烟草生理特性的影响

为探明砷胁迫对烟草生理特性的影响,选用本生烟草(Nicotiana benthamiana)为材料,采用盆栽试验,挑选了生长4周后健壮的烟草苗进行砷(As2O3)胁迫处理(50μg·L-1),并于处理后0、24、48、72和96h分别取样并进行相关生理指标(叶绿素含量、丙二醛含量、超氧化物歧化酶、过氧化物酶和过氧化氢酶活性)的测定.结果显示:随着砷处理时间的延长,本生烟草叶片叶绿素含量、超氧化物歧化酶和过氧化物酶活性呈先升后降趋势,过氧化氢酶活性呈下降趋势,丙二醛含量呈上升趋势.试验数据表明:短时间的砷胁迫烟草会出现自我保护现象,但胁迫超出一定时间(24h)后对烟草造成一定的伤害.     

运用农杆菌介导的瞬时表达体系研究PDS基因沉默

农杆菌介导的瞬时表达体系是一个研究整株植物基因沉默的快速实用系统.本文介绍了运用该系统研究马铃薯X病毒诱导烟草(Nicotiana benthamianan benthamiana)八氢番茄红素脱氢酶(phytoene desaturase,PDS)基因的沉默问题.实验结果表明:携带有与PDS基因同源的409个碱基大小的cDNA片段的重组的马铃薯X病毒载体抑制了内源的PDS基因的表达.     

一个烟草Mlo基因的电子克隆及其序列特性分析

电子克隆并探讨了一个烟草Mlo基因的结构和功能．以GenBank公布的水稻Mlo基因序列为信息探针对烟草的EST数据库进行同源搜索,并将获得的同源性高的EST序列进行序列拼接,最后得到了一个烟草Mlo基因的cDNA序列．采用生物信息学方法分析该基因编码蛋白的一级、二级结构,并对其功能进行预测．结果表明,此烟草Mlo基因...     

过表达本氏烟基因NbPAP2对转基因植物生长发育的影响

为探究紫色酸性磷酸酶基因在本氏烟草中所发挥的生物学功能,该研究利用生物信息学软件发现本氏烟NbPAP2与拟南芥AtPAP2的氨基酸同源性达到64.2%,其具有特征性的信号肽和靶向叶绿体的C端疏水基序以及双核金属离子中心. qRT-PCR结果显示NbPAP2在植物中组成性表达,花瓣中表达量最高,测定叶片气孔导度平均提高30.5%、净光合速率平均提高23%,然而蒽酮比色法测定糖平均含量下降21%.因此,NbPAP2通过介导碳代谢促进本氏烟草花期提前、生物量提高、种子体积增大等.