Identification of lignin-related WRKY transcription factors in the grass Setaria viridis

Author(s)

da Cunha, Lucas Xavier ; de Lima, Leydson Gabriel Alves ; Cesarino, Igor

• Document type: Journal article
• Source: THEORETICAL AND EXPERIMENTAL PLANT PHYSIOLOGY; v. 37, n. 1, p. 16-pg., 2024-12-20.

Abstract

Little is known about the role of WRKY transcription factors in the regulation of the phenylpropanoid and lignin metabolism in grasses. This group of plants differ considerably in terms of vascular patterning and secondary wall composition when compared to eudicots, suggesting the presence of grass-specific molecular and biochemical mechanisms. Here, we performed a genome-wide characterization of the WRKY gene family in the model C4 grass Setaria viridis and the identification of candidate WRKY genes potentially involved in the regulation of phenolic/lignin metabolism. A total of 108 genes encoding WRKYs were found in the S. viridis genome, which were grouped into three phylogenetic groups differing in the number of WRKY domains and the structure of their zinc-finger motifs. The selection of candidate lignin-related WRKYs was performed using a combination of comparative phylogenetic analysis, high-throughput expression analysis, and RT-qPCR. Seven SvWRKYs were selected as potential candidates to play a role in the regulation of developmental lignification in S. viridis based on (1) orthologous relationships with WRKYs previously shown to play a role in lignification in other plant species, (2) similar expression pattern to that of lignin-related genes in public transcriptomic databases, (3) similar expression pattern to that observed for lignin biosynthetic genes in the S. viridis elongating internode, and (4) high expression in S. viridis tissues undergoing active lignification. Functional characterization of our candidate SvWRKYs using reverse genetics might provide more definitive evidence of their involvement in the lignification process in C4 grasses. (AU)

• FAPESP's process: 21/06142-8 - Steering the shikimate/phenylpropanoid pathway: from gene function discovery to green factories
• Grantee: Igor Cesarino
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Young Investigators Grants - Phase 2
• FAPESP's process: 22/09003-1 - A systemic view of phenolic and lignin metabolism in the model grass Setaria viridis
• Grantee: Leydson Gabriel Alves de Lima
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)