标题双胚苗水稻中单倍体和二倍体不同器官的cDNA- AFLP分析

SARII-628是四川农业大学水稻研究所的一个双胚苗自然群体, 每年都能定期分离出单倍体与二倍体(n:2n)。文章对单倍体和对应的二倍体进行了cDNA-AFLP分析。合成了3个单倍体和1个二倍体的根、茎、穗和叶的cDNA, 用EcoR I/ Msp I酶切组合, 通过cDNA-AFLP技术统计这16个样本的表达差异。共选用30对引物, 在633条扩增位点上筛选出49个有差异表达的序列。结果:(1)单倍化后cDNA-AFLP总体水平虽然在各单株间略有差异但变化不大, 表达变化的位点所占比例平均为5.14%, 高于二倍体的3.93%; (2)根据样本在根、茎、穗和叶中表达出带的有无, 在扩增出的14种带型中, 有4种只出现在单倍体中, 其对应位点的表达具有单倍体的特异性; (3)对这3个单倍体在不同器官的激活和沉默位点进行汇总, 发现在根和穗中, 发生沉默的位点多于激活的位点数, 而在茎和叶中的结果正好与之相反, 但是在单倍体的所有器官中发生激活变化的位点多于沉默变化的位点; (4)对不同器官中的发生表达变化(激活+沉默)位点分析, 发现根中的变化位点最多, 在穗中的变化最少, 说明位点的表达变化具有器官特异性。

cDNA-AFLP analysis among different organs of haploid and diploid plants in twin-seedling rice

SARII-628 is one of the natural twin-seedling populations, which are maintained in Rice Institution of Sichuan Agricultural University. Haploid-diploid (n: 2n) twin-seedlings can annually emerge from SARII-628. In this study, cDNA-AFLP technique was applied for these haploid and diploid plants. The double stranded cDNA were synthesized from the total RNAs of the roots, stems, panicles, and leaves of three haploid and one diploid plants. Then, EcoRI/MspI combina-tion was chosen for expression difference analysis with cDNA-AFLP technique among the 16 samples. Thirty pairs of primers were selected to amplify 633 loci. Among them, 49 loci were differently expressed. As shown by cDNA-AFLP, the expression levels of haploids were different among individuals but not significant. The average ratio of sensitive loci (acti-vated loci + silenced loci) in haploids was 5.14%, which was higher than that of diploid (3.93%). According to the presence or absence of the bands in root, stem, panicle, and leaf, out of the 14 types of amplified patterns, only 4 exclusively oc-curred in haploid and the corresponding loci were thus haploid-specific in expression. The collecting analysis for the si-lenced and activated loci among different organs of the three haploids revealed that the silenced loci were more than the activated ones in roots and panicles. An opposite trend was observed in panicles and leaves. However, the total number of the activated loci in all the four types of haploid organs was more than that of the silenced loci. The number of sensitive loci is the highest in root, while that in panicle is the least, which suggested that gene expressions were organ-specific.