Mutator诱导的玉米白化突变体插入位点的遗传分析及代谢途径的构建

【目的】利用Mutator(Mu)诱变群体获得、验证叶色白化突变体的Mu因子插入位点;解析玉米叶色变异相关基因及其代谢网络。【方法】以含有活性MuDR转座子的W22∷Mu为父本,与玉米自交系综31(Z31)杂交产生的M2和M3家系群体为材料,经表型性状的遗传分析和Mu插入位点的分离获得白化突变体,经生物信息学方法解析白化突变体产生的相关基因,同时构建产生白化突变代谢网络。【结果】对870个M2家系的16000余单株和M3种植的36个家系近700单株进行考察,获得了遗传稳定的白化突变体41株。经Mu-TAIL-PCR分析获得35条Mu因子插入序列;对靶位点序列分析,获得的14个靶位点可能与叶绿素合成及光合作用有关;利用其中6个靶位点构建了5条玉米叶色突变产生白化的叶绿素代谢网络途径。【结论】初步证实了Mu转座子插入的27个靶位点与叶色白化突变体的关联;建立了6个靶位点的玉米叶色突变产生白化的叶绿素代谢网络途径。

Genetic Analysis and Construction of Metabolic Pathway by Mutator-Mediated Albino Mutatant Insertion Sites in Zea mays L.

【Objective】 A study was conducted to obtain and validate the Mutator(Mu)insertion sites causing albino mutant in the mutagenic population with Mu elements, clone the candidate genes associated with maize albino mutation and analyze the metabolic network among these genes. 【Method】 W22∷Mu containing active MuDR transposon was used to pollinate the elite maize inbred line Z31. Using the M2 and M3 families produced from the above hybrid, the albino mutant was obtained by genetic analysis of phenotype and isolation of Mu insertion sites using Mu-TAIL-PCR. The obtained associated genes causing albino mutation was analyzed by bioinformatics and a metabolic network of these genes was constructed. 【Result】 Forty-one albino seedlings were found within 16 000 plants of 870 M2 families and about 700 plants of 36 M3 families. Thirty-five Mu insertion target sequences were cloned by Mu-TAIL-PCR, among which 14 were found to be related with chlorophyll synthesis and photosynthesis. Five metabolic pathways causing albino mutation were constructed with 6 target sequences. 【Conclusion】 The preliminary confirmation was that the 27 target sites by Mutator transposon insertion associated with the albino mutatants, meanwhile we constructed chlorophyll metabolic network pathway through six target sites from albino mutation of maize leaf.