Interaction between Rag genes results in a unique synergistic transcriptional response that enhances soybean resistance to soybean aphids

BMC Genomics

Chantal E. McCabe¹  Michelle A. Graham²  Asheesh K. Singh³  Yunhui Qi⁴  Jessica D. Hohenstein⁵  Gustavo C. MacIntosh⁵  Martha I. Natukunda⁵ 

[1] Corn Insects and Crop Genetics Research, USDA-ARS, 50011, Ames, IA, USA;Corn Insects and Crop Genetics Research, USDA-ARS, 50011, Ames, IA, USA;Department of Agronomy, Iowa State University, 50011, Ames, IA, USA;Department of Agronomy, Iowa State University, 50011, Ames, IA, USA;Department of Statistics, Iowa State University, 50011, Ames, IA, USA;Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, 50011, Ames, IA, USA;

关键词: Gene pyramiding;    Soybean;    Soybean aphids;    Aphid resistance;    Rag;    RNA sequencing;    Synergistic effect;   

DOI  :  10.1186/s12864-021-08147-3

来源: Springer

【 摘 要 】

BackgroundPyramiding different resistance genes into one plant genotype confers enhanced resistance at the phenotypic level, but the molecular mechanisms underlying this effect are not well-understood. In soybean, aphid resistance is conferred by Rag genes. We compared the transcriptional response of four soybean genotypes to aphid feeding to assess how the combination of Rag genes enhanced the soybean resistance to aphid infestation.ResultsA strong synergistic interaction between Rag1 and Rag2, defined as genes differentially expressed only in the pyramid genotype, was identified. This synergistic effect in the Rag1/2 phenotype was very evident early (6 h after infestation) and involved unique biological processes. However, the response of susceptible and resistant genotypes had a large overlap 12 h after aphid infestation. Transcription factor (TF) analyses identified a network of interacting TF that potentially integrates signaling from Rag1 and Rag2 to produce the unique Rag1/2 response. Pyramiding resulted in rapid induction of phytochemicals production and deposition of lignin to strengthen the secondary cell wall, while repressing photosynthesis. We also identified Glyma.07G063700 as a novel, strong candidate for the Rag1 gene.ConclusionsThe synergistic interaction between Rag1 and Rag2 in the Rag1/2 genotype can explain its enhanced resistance phenotype. Understanding molecular mechanisms that support enhanced resistance in pyramid genotypes could facilitate more directed approaches for crop improvement.

【 授权许可】

CC BY