Functional marker mapping of protein phosphatase 2a structural subunit gene tapp2aa in common wheat | 小麦蛋白磷酸酶2A结构亚基基因TaPP2Aa的功能标记作图

Chinese. 【目的】开发小麦抗旱相关蛋白磷酸酶结构亚基基因TaPP2Aa的功能标记并作图，为分子标记辅助选择抗逆育种提供依据。【方法】测序得到普通小麦及其野生近缘种TaPP2Aa的基因序列，分析其SNP位点差异，设计3对基因组特异引物和6对基因组内等位基因特异引物，利用中国春缺四体对TaPP2Aa进行染色体定位，利用RIL群体（Opata 85×W7984）和DH群体（旱选10号×鲁麦14）进行该基因的功能标记作图。【结果】TaPP2Aa定位于小麦第5同源染色体群上；TaPP2Aa-B位于RIL群体5B的标记区间Xwg909―Xgwm67，与2个标记的遗传距离分别为4.0 cM和3.6 cM，在DH群体5B染色体的标记区间Xgwm234―WMC363，与WMC363的遗传距离为7.5 cM；在2个遗传群体中与标记Xgwm67的距离分别为3.6 cM和11.4 cM。TaPP2Aa-D位于RIL群体染色体5D的标记区间Xcmwg770―Xbarc205，遗传距离分别为9.8 cM和10.0 cM。【结论】确定了TaPP2Aa所在的染色体位置，通过与DH和RIL 2个遗传作图群体中已有的抗逆主效QTL进行对比分析，明确了TaPP2Aa与小麦抗逆性状QTL具有遗传连锁关系，开发的功能标记可用于小麦抗逆性状的分子标记辅助选择。

English. 【Objective】The purpose of the present research was to develop functional markers of protein phosphatase 2A structural subunit gene PP2Aa in common wheat (Triticum aestivum L.) for marker assisted selection in breeding of drought tolerance. 【Method】Based on the single nucleotide polymorphism (SNP) in the sequences of PP2Aa gene in common wheat and its wild relative species, three genome-specific primer pairs and six allele-specific primer pairs were designed. The Chinese Spring nulli-tetrasomic lines, a recombinant inbred line (RIL) population (Opata 85 × W7984) and a doubled haploid (DH) population (Hanxuan 10 hao× Lumai 14) were used for genetic location and mapping of TaPP2Aa. 【Result】The TaPP2Aa gene was located on chromosomes 5A, 5B and 5D. TaPP2Aa-B was mapped in the intervals between markers Xwg909 and Xgwm67 on chromosome 5B in RIL population, 4.0 cM and 3.6 cM from the flanking markers, and between markers Xgwm234 and WMC363 on chromosome 5B in DH population, 7.5 cM from WMC363, 3.6 cM and 11.4 cM from the common marker Xgwm67 in two populations, respectively. TaPP2Aa-D was mapped in the interval between markers Xcmwg770 and Xbarc205 on chromosome 5D in RIL population, 9.8 cM and 10.0 cM from them. 【Conclusion】The present study mapped the TaPP2Aa on the homoeologous chromosomes 5A, 5B and 5D.Through comparative analysis with main effect QTLs for stress resistance in DH and RIL genetic populations, the genetic linkage between TaPP2Aa and stress-resistant QTLs was identified. The functional markers developed for TaPP2Aa-B and TaPP2Aa-D can be used for marker assisted selection to enhance the efficiency of wheat stress-tolerant improvement.