Frequency of microsatellite sequences in rice (Oryza sativa L.).
Frequency of microsatellite sequences in rice (Oryza sativa L.).
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DOI：
10.1139/g95-155
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发表时间：
1995-12
期刊：
影响因子：
3.1
通讯作者：
O. Panaud;Xiuli Chen;S. McCouch
中科院分区：
文献类型：
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作者：
O. Panaud;Xiuli Chen;S. McCouch
本研究旨在估计水稻基因组中 13 个微卫星基序的相对频率，作为有效开发微卫星图谱的基础。两个二核苷酸、七个三核苷酸和四个四核苷酸重复基序被末端标记并用作杂交探针来筛选水稻cv.的基因组和cDNA文库。红外36。根据接近 Td 的洗涤温度（解离温度；Td = Tm - 7.6 摄氏度）估计用于鉴定含有特定微卫星基序的克隆的最佳洗涤温度。对对应于 4 个微卫星基序中的每一个的 20 个假定阳性克隆进行测序表明，虽然 Td 为大多数研究的重复序列提供了洗涤严格性的有用预测因子，但那些具有非常高 GC 或 AT 含量的克隆最容易出错。水稻基因组文库的筛选结果表明，水稻基因组中估计有 1360 个聚（GA）n 和 1230 个聚（GT）n 微卫星，并且不同重复的相对频率随着基序大小的增加而降低。 cDNA文库中最常观察到的微卫星与基因组文库相同，但本研究中的cDNA中没有观察到聚(CGG)n、聚(ATC)n或四核苷酸基序。
This study was undertaken to estimate the relative frequencies of 13 microsatellite motifs in the rice genome as a basis for efficient development of a microsatellite map. Two dinucleotide, seven trinucleotide, and four tetranucleotide repeat motifs were end labelled and used as hybridization probes to screen genomic and cDNA libraries of rice, cv. IR36. Optimal washing temperatures for identification of clones containing specific microsatellite motifs were estimated based on washing temperatures near Td (dissociation temperature; Td = Tm - 7.6 degrees C). Sequencing of 20 putatively positive clones corresponding to each of 4 microsatellite motifs suggested that while Td provides a useful predictor of washing stringency for most of the repeats studied, those with a very high GC or AT content were most prone to error. The results from screening the rice genomic library suggest that there are an estimated 1360 poly(GA)n and 1230 poly(GT)n microsatellites in the rice genome, and that the relative frequency of different repeats decreased with increasing size of the motif. The most frequently observed microsatellites in the cDNA library were the same as for genomic library, but no poly(CGG)n, poly(ATC)n, or tetranucleotide motifs were observed among cDNA in this study.