【作者】 石垚；

【导师】 徐子勤；

【作者基本信息】 西北大学 ， 细胞生物学， 2010， 硕士

【摘要】 拟南芥(Arabidopsis thaliana)是一种模式植物,属于十字花科(Cruciferae)拟南芥属(Arabidopsis),具有基因组小、生命周期短等特点,近年来已被广泛用于功能基因组学研究领域,并已取得大量的研究成果。EARLI1基因编码一个大小为14.7kDa、定位于细胞壁的蛋白质,是脯氨酸富含蛋白(PRP)家族成员。EARLI1基因已被证明具有抵抗低温胁迫和真菌侵染的功能。本工作的主要目的是通过生理学、组织化学和分子生物学等实验手段,进一步研究和探索EARLI1基因的功能。显微观察结果显示,EARLI1与拟南芥叶片细胞的形态建成有关。通过组织化学染色发现EARLI1还参与了花序茎中木质素的合成调控过程。野生型和EARLI1 RNA干扰植株花序茎中的木质素含量平均值分别为9.67%和8.76%。表达分析表明木质素合成的关键酶CCR(肉桂酰辅酶A还原酶)受EARLI1转录水平的影响。EARLI1还能够在很大程度上调节拟南芥的开花过程。下调EARLI1表达水平会使开花时间明显提前。野生型和EARLI1 RNA干扰植株开花所需时间平均分别为39.7天和19.4天。二者的主茎长、节间数、莲座叶数统计数据也有明显差异。RT-PCR结果显不EARLI1可能是通过自主途径维持FLC(FLOWERING LOCUS C)的表达,从而延迟开花的。用过氧化氢处理Col-FRI-Sf2和RNAi Col-FRI-Sf2植株,并统计萌发率、根伸长量等数据,发现RNA干扰植株比野生型对胁迫条件更加敏感,它的种子萌发率在过氧化氢浓度为5mmol/L时相对于野生型有显著下降,而根伸长量则在0.1mmol/L和0.5mmol/L过氧化氢处理时明显低于野生型。用100mmol/L的过氧化氢处理不同时间,RNA印迹分析结果显示过氧化氢确实能够诱导EARLI1基因表达。更多还原

【Abstract】 Arabidopsis thaliana is a model plant, it belongs to Cruciferae. In recent years, Arabidopsis has been widely used in fields related to functional genomics owing to its advantages such as small genome and short life cycle, and has made a lot of research achievements. EARLI1 gene encodes a 14.7kDa protein located in cell wall, it is a member of PRP (proline-rich protein) family. EARLI1 has been documented to have multiple functions including resistance to low temperature and fungus infection. The main purpose of this study is to further study the function of EARLI1 gene with physiology, histochemistry, molecular biology or other experimental methods.Microscopic observation showed that EARLI1 is associated with the morphogenesis of leaf cells in Arabidopsis. Through the histochemistry study, EARLI1 was found to be involved in regulation of lignin synthesis in inflorescence stems. The mean value of lignin content in inflorescence stems of Col-FRI-Sf2 and RNAi Col-FRI-Sf2 plants were 9.67% and 8.76% respectively. Expression analysis of EARLI1 revealed that CCR, a key enzyme in lignin synthesis, could be affected by EARLI1.EARLI1 also can control the flowering process to a large extent in Arabidopsis. RNAi Col-FRI-Sf2 plants of EARLI1 flowered earlier than Col-FRI-Sf2 wild type plants. The average flowering time of Col-FRI-Sf2 and RNAi Col-FRI-Sf2 were 39.7 and 19.4 days, respectively. There are significant differences in main stem length, internode number and rosette leaf number between Col-FRI-Sf2 and RNAi Col-FRI-Sf2 plants. The results of RT-PCR showed that EARLI1 might delay the flowering time through the autonomous pathway by maintaining the abundance of FLC transcripts.Hydrogen peroxide was used to treat Col-FRI-Sf2 and RNAi Col-FRI-Sf2 plants. The changes in germination rate of seeds, elongation of root length and other data were analyzed statistically. The results showed that RNA interference plants is much more sensitive to hydrogen peroxide than the wild type plants. Compared to wild-type plants, the seed germination rate of RNA interference lines under 5mmol/L hydrogen peroxide concentration decreased significantly. The root length elongation of RNAi lines subjected to O.lmmol/L, 0.5mmol/L hydrogen peroxide treatment was significantly lower than wild-type plants. RNA blotting analysis showed that the expression of EARLI1 gene could be induced definitely by 100mmol/L hydrogen peroxide for different time.更多还原