Identification And Comparative Analysis Of CBS Domain Containing Proteins In Soybean (Glycine Max) And The Primary Function Of GMCBS21 In Enhanced Tolerance To Low Nitrogen Stress

Improving soybean and N management is required to optimize crop production and reduce environmental risks due to N losses. Although there are many studies on the molecular mechanism of nitrogen absorption and utilization in soybean, exploreing new ways to improving NUE could provide theoretical basis for the cultivation of high nitrogen efficiency soybean cultivars. The study based on modern molecular biology and transgenic technology, and combined with a new generation of high-throughput sequencing technology. A candidate gene GmCBS21 for NUE was identified and analysis. Cystathionine beta synthase (CBS) domain-containing proteins (CDCPs) may be implicated in abiotic stress tolerance in plants. We identified and classified a CBS domain-containing protein family in soybean. A candidate gene for NUE, GmCBS21, was identified. GmCBS21 gene characteristics, the temporal expression pattern of the GmCBS21 gene, and the phenotype of GmCBS21 overexpression in transgenic Arabidopsis thaliana under low nitrogen stress were analyzed. The phenotypes suggested that the transgenic Arabidopsis thaliana seedlings performed better under the nitrogen-deficient condition. GmCBS21-overexpressing transgenic plants exhibit higher low nitrogen stress tolerance than WT plants.To further analysis of low nitrogen tolerance mechanism underlying overexpressing GmCBS21gene, RNA-seq and yeast two-hybrid method were used. We analyzed the dynamic transcriptome of GmCBS21 transgenic Arabidopsis under low nitrogen stress. Much of differentially expressed genes were shown, especially for up-regulated genes. Including known NUE genes, transcription factors, kinases, genes involved in photosynthesis.By yeast two-hybrid method, a total of 40 candidate positive clones were sequenced and analyzed through BLAST. Function prediction of the candidate proteins suggested that GmCBS21 was possibly involved in several pathways. This work would provide a basis for a defined further functional dissection of GmCBS21 function in soybean NUE.