拟鹅观草St基因组ISSR特异标记的建立

以拟鹅观草(Pseudoroegneria spicata)、中间偃麦草(Thinopyrum intermedium)、长穗偃麦草(Th.elonga-tum)、二倍体簇毛麦(Dasypyrum villosum)、澳冰草(Australopyrum retrofractum)等10份小麦族物种为材料,对100条ISSR引物进行分析,结果显示引物811可以在拟鹅观草(GenBank登录号为EU368859)和中间偃麦草中扩增出一条长441 bp的特异DNA片段命名为St441,而其它供试物种均未扩出.经序列比对、软件分析结合原位杂交结果认为St441为一类新的低拷贝重复序列.利用ISSR引物811对10份不同居群的中间偃麦草、20份披碱草属物种、4份小麦-偃麦草部分双二倍体、6份小麦-茸毛偃麦草后代和12份小麦对照进行扩增,结果发现除对照小麦外均能扩增出St441;进而对小麦-中间偃麦草两套附加系进行扩增,将St441初步定位于包括第四同源群在内的8条St染色体上.同时,发现只含有整条St染色体和St染色体片段的材料能扩增出St441,而仅有Js染色体的材料未扩增出St441.因此,该标记St441可以作为检测不同背景下St染色质的分子标记.

Development of St Genome Specific ISSR Marker

In this study,one hundred of inter simple sequence repeat(ISSR) primers were investigated on Pseudoroegneria spicata,Thinopyrum intermedium,Th.elongatum,Dasypyrum villosum,Australopyrum retrofractum and other five triticeae species.A 441 bp specific DNA fragment(GenBank accession No.EU368859),designated as St441,was obtained from Ps.spicata by primer 811 and the DNA band was also amplified from Th.intermedium,while no St441 in other 8 triticeae species.Based on the results of sequence analysis and fluorescence in situ hybridization(FISH),we proved that St441 is a new low-copy repetitive sequence.10 Th.intermedium from different populations,20 Elymus species,4 wheat-Th.intermedium amphiploids,6 wheat-Th.intermedium subsp.trichophorum offsprings were surveyed with 12 common wheat as control to testify the availability of marker St441.As consequence,St441 appeared in all test materials except common wheat.Furthermore,based on the amplification of two sets of wheat-Th.intermedium addition lines,St441 was located on,at least,8 St chromosomes involving homoeologous group 4.Meanwhile,the result indicated that St441 amplified only from species containing St chromosomes and St segments,other than Js chromosomes.Therefore,St441 could be a molecular marker targeting St chromatin on different genetic backgrounds.