结球甘蓝NBS-LRR类R基因同源序列的分离

Isolation of Resistant Gene Analog of NBS-LRR from Cabbage

根据大多数抗病基因编码蛋白质的核苷酸结合区(NBS)和富含亮氨酸重复序列(LRR)保守区域的特点,设计PCR特异简并引物,从抗TuMV的结球甘蓝材料84075中,扩增出513 bp的DNA片段,经克隆、测序后,得到4个含有NBS-LRR保守区域的R基因同源序列,分别命名为:Bor1、Bor2、Bor3和Bor4,同源性比较分析表明,它们与已克隆的抗病基因或抗病基因片段有不同程度的同源性。以Bor1为探针,对84075进行Southern blot和RFLP分析的结果表明,Bor1以多拷贝形式存在。

The PCR degenerate primers were designed from the conservative domain NBS-LRR (nucleotide binding siteand leucine-rich repeat) of most resistant disease genes in plants. The DNA fragments of 513 bp were amplified by genomicDNA and cDNA PCR of cabbage resistant material 84075, then cloned into multi-clone site of pUCm-T, transformed intoEscherichia coli DH5α, and sequenced. Four resistant gene analogs which contain NBS-LRR domain were obtained,named as Borl, Bor2, Bor3, Bor4. Their amino acid sequences have different homology scores compared with that ofresistance gene or resistance gene analog from other plants in Gene Bank. Using Bor1 as probe, Southern blot with genomicDNA of 84075 and RFLP analysis show Bor1 may be exist multi-copy.