【摘要】 通过对胚珠DNA的SSR标记分析,在DNA水平上检测氮离子束诱变后胚珠的多态性变化,结果表明,离子注入陆地棉花粉后再授粉雌蕊,会对胚珠的DNA多态性产生影响,表明在一定程度上改变了花粉中精细胞的DNA序列;利用抑制性消减杂交(SSH)分离N+离子诱变花粉和正常花粉(对照)分别给雌蕊授粉后产生的M1代植株叶片间表达有差异的cDNA片段,建立差异表达cDNA文库。已测序的有50个缩减cDNA克隆,根据BLAST网络服务检索查询EMBL、Gen Bank、DDBJ和PDB的核苷酸序列数据库以及蛋白质氨基酸序列数据库,进行序列联配,结果发现52%序列在数据库中都有同源的棉属来源的EST。38个EST与其他物种已知基因部分区域的同源性为56%~100%,占总EST的76%;5条EST序列能在数据库中检索到同源性序列,但其功能(占10%)尚不清楚;9个EST能在数据库中发现为推测蛋白,占18%;4个EST在GenBank中没有查到对应的同源序列,占8%。更多还原

【Abstract】 The SSR-based molecular markers technique was used to determine the polymorphism change of ovule DNA of Gossypiom hirsutum L.after N⁺ ion implantation.The results showed that the ovule DNA polymorphism were changed,which indicated that the DNA sequences of sperm cell were altered.The ovule was developed after the pistils were pollinated by the pollen grains which had been implanted with nitrogen ions.The suppressive subtraction hybridization（SSH） technique was used to isolate the cDNA fragments that showed differential expression between the M₁ progeny developed after the pistils were pollinated by the pollen grains implanted with nitrogen ions and the nature "Sumian 22" as control.Two differential expression cDNA libraries were constructed using the cDNAs of the treated M₁ progeny as driver and the cDNAs of untreated M₁ progeny as tester,vice versa.The results demonstrated that the insertion fragments of SSH library were ranging from 450 to 700 bp.50 clones were randomly picked for PCR and sequencing.After matching the results in GenBank dbEST and the Blastn,50 sequences were obtained.Of them,38 of them had 56%～100% similarity with known genes, which was 76% of the total EST;5 sequences had their homology with the sequences in GenBank with unknown function,which was 10% of the total EST;9 were hypothetical protein,which was 18% of the total EST;4 had no similarity with the sequences in GenBank,which might be new genes;or the gene could not search the similarity with the sequences of other species,because the sequences located in the easy-varied 3’-end,which was 8% of the total EST.更多还原