Isolation and Functional Verification of Genes Mediating Mineral Element Stress Tolerance in Lotus
[Objective]Lotus(Nelumbo nucifera)is a traditional edible and medicinal homologous crop in China,yet its abundant genetic resources lack functional characterization.This research aimed to functionally identify genes involving in the accumulation/tolerance of trace mineral nutrients and heavy metal elements in lotus,thereby accumulated gene resources that facilitated increased nutrient efficiency and stress tolerance,so as to provide a theoretical basis for the genetic improvement of lotus.[Method]The representative Xianglian lotus variety,Cunsanlian was used as the experimental material.Initially,a yeast expression cDNA library of lotus was constructed and transformed into Saccharomvces cerevisiae.It was then screened on plates containing excessive cadmium(Cd),manganese(Mn),zinc(Zn),copper(Cu),iron(Fe),and aluminum(Al)stress to isolate target genes mediating stress tolerance in positive yeast clones.Finally,the functional verification of the selected tolerance genes was conducted through combining bioinformatics analysis and yeast complementation verification.[Result]A yeast cDNA library of lotus was constructed with a capacity exceeding 106 yeast monoclonal clones,a recombination rate of 100％,and an average insertion fragment size greater than 1 000 bp.Following the screening on stress plates,13 genes for Cd tolerance,4 for Mn tolerance,4 for Zn tolerance,3 for Cu tolerance,7 for Fe tolerance,and 1 for Al tolerance were identified.Among these,3 genes were able to mediate tolerance to both Fe and Mn.These genes were distributed on all lotus chromosomes except chromosome 6.[Conclusion]A high-quality yeast expression cDNA library of lotus was constructed,and screened 29 genes mediating resistance to excess trace mineral nutrients or heavy metal elements,accumulating gene resources for lotus genetic improvement for enhanced nutrient efficiency and the prevention of heavy metal accumulation.
万方数据
维普
