Randhawa H S, Dilbirligi M, Sidhu D, Erayman M, Sandhu D, Bondareva S, Chao S, Lazo G R, Anderson O D, Gustafson J P, Echalier B, Qi L L, Gill B S, Akhunov E D, Dvorák J, Linkiewicz A M, Ratnasiri A, Dubcovsky J, Bermudez-Kandianis C E, Greene R A, Sorrells M E, Conley E J, Anderson J A, Peng J H, Lapitan N L V, Hossain K G, Kalavacharla V, Kianian S F, Pathan M S, Nguyen H T, Endo T R, Close T J, McGuire P E, Qualset C O, Gill K S
Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420, USA.
Genetics. 2004 Oct;168(2):677-86. doi: 10.1534/genetics.104.034843.
To localize wheat (Triticum aestivum L.) ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions (bins) flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 (loci) were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin.
为了将小麦（Triticum aestivum L.）的ESTs定位到染色体上，通过将来自37个cDNA文库的7965个单拷贝序列物理定位到146个染色体、染色体臂和亚染色体臂非整倍体及缺失系中，鉴定出了882个第6同源群特异性ESTs。这882个ESTs被物理定位到由23个缺失断点界定的25个区域（bin）。在882个ESTs检测到的5154个限制性片段中，2043个（位点）被定位到第6组染色体上，806个被定位到其他染色体组上。定位到的位点数量在6B染色体上最多，在6D染色体上最少。使用一种限制性内切酶在所有三个同源染色体上检测到直系同源位点的264个ESTs被用于构建一个一致性物理图谱。ESTs在染色体上的物理分布不均匀，在染色体臂的远端半部有更高密度的趋势。在比较基因组序列时，约43%的小麦第6组ESTs鉴定出了水稻同源物。这些ESTs中有58%存在于水稻第2染色体上，其余的存在于其他水稻染色体上。即使在第6组bin内，由1 - 6个小麦ESTs鉴定出的水稻染色体区段与多达11条水稻染色体同源。这些水稻区段重叠群被用于解析每个bin内小麦ESTs的顺序。
