小麦对缺锌胁迫响应的转录组分析OA

Zinc(Zn)is one of the essential micronutrients for the growth and development of animals and plants,and living organisms can only acquire it through external intake.Wheat is one of the three major staple food crops globally,and even serves as the primary staple food crop in regions deficient in Zn nutrition.Enhancing Zn content in wheat grains via molecular design breeding is an efficient strategy to alleviate the issue of hidden hunger in these areas.Based on compa-ring Zn accumulation capacity among multiple wheat germplasm accessions,this study selected Zhongmai 175,a wheat va-riety with high Zn accumulation efficiency,for Zn deficiency stress treatment.It was found that compared with the control(without Zn deficiency),indicators including total root length,root volume,root surface area,average root diameter,and number of root tips significantly increased in the early stage of stress.Further transcriptome analysis revealed that under Zn deficiency stress,there were 1 936 and 2 287 differentially expressed genes(DEGs)in the roots and leaves of Zhongmai 175,respectively.GO analysis showed these DEGs were mainly enriched in terms such as ion transmembrane transporter activity,ion homeostasis,metal ion transport,zinc ion transport,and plant hormone signa-ling pathways.KEGG analysis indicated that DEGs in leaves were primarily enriched in the cysteine and methionine metabolism pathways.Among them,genes involved in the biosynthesis of mugineic acids(e.g.,SAM and NAAT)and genes related to ethylene synthesis(e.g.,ACO and ACS)were significantly up-regulated.DEGs in roots were mainly enriched in the phenylpropanoid biosynthesis pathway,and key genes involved in lignin synthesis(e.g.,CCR,CAD,COMT,and LAC genes)were significantly down-regulated.It is hypothesized that Zhongmai 175 may improve the absorption efficiency of Zn ions in roots by reducing the ability of cell walls to retain metal ions under Zn-deficient conditions.The results of this study provide genetic resources for deciphering the molecular mechanisms of Zn absorption and accumulation in wheat,as well as for Zn biofortification breeding.