Construction of a high density linkage map of Lentinula edodes by the gene mapping.

我们先前已经基于203个AFLP（扩增片段长度多态性）标记的分离构建了香菇（Lentinula edodes）的遗传连锁图谱（Terashima等人，2002年）。本研究的目的是通过基因标记的开发和定位，在标记密度和标记间连锁关系的准确性方面改进我们以前的连锁图谱。结果如下：（1）根据L. edodes发达。(2)将这29个cDNA标记划分为7个连锁群，构建了由11个连锁群组成的AFLP连锁图。该图谱全长1907.7厘摩（cM），平均标记间距9.2cM，由11个连锁群组成连锁群Ⅰ，344.8cM，42个标记，连锁群Ⅱ，257.1cM，40个标记，连锁群Ⅲ，248.6cM，28个标记，连锁群Ⅳ，216.1cM，25个标记，连锁群Ⅴ，207.1cM，26个标记; LG VI，174.8cM，18个标记; LG VII，168.4cM，19个标记; LG VIII，129.4cM，19个标记; LG IX，97.9cM，6个标记; LG X，44.9cM，7个标记; LG Xi，18.6cM，4个标记。(3)约50%的277个cDNA序列（平均大小，约1.2kb）显示与日本DNA数据库（DDBJ）中登记的序列具有显著的同源性，其概率小于<-10>预期值（E值）的10%。本研究所构建的遗传连锁图谱有助于苜蓿分子育种研究的发展。edodes，因为cDNA标记能够用作组合来自不同群体的图谱的锚标记。

We have previously constructed the genetic linkage map of the shiitake mushroom, Lentinula edodes, based on the segregation of 203 AFLP (Amplified Fragment Length Polymorphism) markers (Terashima et al., 2002). The aim of this study is to improve our previous linkage map in terms of the marker density and the accuracy of the linkage relationships among markers by the development of gene markers and the mapping of them. The results were as follows ; (1) Eighty-five gene (cDNA) markers which are amplified with the PCR primers designed from the cDNA sequence of L. edodes were developed. (2) The 29 cDNA markers were assigned into 7 linkage groups of the previous AFLP-based linkage map which consists of 11 linkage groups. The map re-constructed has a total length of 1907.7 centimorgans (cM) with an average interval between markers of 9.2 cM and is comprised of 11 linkage groups as follows ; LG I (Linkage group I), 344.8cM, 42 markers ; LG II, 257.1cM, 40 markers ; LG III, 248.6cM, 28 markers ; LG IV, 216.1cM, 25 markers ; LG V, 207.1cM, 26 markers ; LG VI, 174.8cM, 18 markers ; LG VII, 168.4cM, 19 markers ; LG VIII, 129.4cM, 19 markers ; LG IX, 97.9 cM, 6 markers ; LG X, 44.9 cM, 7 markers ; LG XI, 18.6 cM, 4 markers. (3) About 50 % of cDNA-sequences of 277 (the average size, about 1.2 kb) showed significant homology to the sequences registered in the DNA Data Bank of Japan (DDBJ) with less than 10^<-10> of expected value (E-value) probability. The improved linkage map in this study would contribute to the developments of the research on molecular breeding of L. edodes, because the cDNA markers are able to use as an anchor marker for combining maps from different populations.