The plant-specific NAC (NAM, ATAF, and CUC) transcription factor (TF) family has been widely described as crucial regulators associated with various biological processes in the plant kingdom, including organogenesis, tissue development and stress response. Despite of the important roles of NAC TF family, its identification, expression, and function in lotus remain largely unknown at present.
The research team from Wuhan Botanical Garden identified and characterized the NnNAC gene family from sacred genome. In addition, potential NnNAC candidate genes associated with lotus seed development and complete submergence stress response were predicted, respectively.
A total of 82 NnNAC genes were systematically characterized in the lotus genome. The homologous gene pairs displayed similar conserved motifs and gene structure characteristics. The research revealed an extensive transcriptional activation capacity mediated by the highly divergent C-terminal activation domain (AD). In addition, 30 NnNAC differentially expressed genes (DEGs) during lotus seed development were identified, and 29 NnNAC DEGs associated with submergence stress response were identified in the lotus genome.
This study not only extends our knowledge on the NnNAC gene family, but also lays a vital theoretical foundation for the molecular breeding and germplasm innovation of lotus in future.
Research was funded by the National Natural Science Foundation of China, the Biological Resources Program, CAS, and the Hubei Provincial Natural Science Foundation of China.
Genome scale synteny analysis and transcriptional activation assay of NnNAC genes. (A) Syntenic relationship of NnNAC genes. (B) Transactivation assay of NnNAC proteins in the Y2H system. (C) Schematic representation of NnNAC protein truncations (Image by WBG)
