Decoding steroid-derived metabolite engineering in Solanum

Abstract

Steroidal glycoalkaloids (SGAs) and steroidal saponins (STSs) play significant role in the plant defence against pests and offer various pharmaceuticals applications. SGAs and STSs generally share common biosynthetic pathways in Solanum, originating from a furostanol scaffold. Despite the discovery of multiple GLYCOALKALOID METABOLISM (GAME) genes involved in the biosynthesis of these compounds, previous attempts for the metabolic engineering of these pathways have remained unsuccessful. The GAME15 protein, with its dual enzymatic roles, has unlocked a mystery surrounding the intricate process of metabolizing cholesterol. This protein not only acts as a glucuronosyltransferase but also serves as a metabolic scaffold, organizing several proteins for the proper functioning. This mini review briefly describes the molecular mechanisms and functional dynamics of GAME genes, particularly focusing on GAME15 as a key game changer gene and its role in metabolite channelling, regulation of pathway, and ecological importance. We highlighted the potential of this discovery for advancing metabolic engineering in crop improvement and the pharmaceutical industry. This finding opens doors for designing crops that are resistant to pests. Additionally, we identify important future research directions, including the regulatory mechanisms of these pathways and uncovering structural aspects of pivotal enzymes.

Acknowledgments

This work was supported by the Hainan Provincial Natural Science Foundation of China (no. 323CXTD373), the National Natural Science Foundation of China (nos 32460072, 32100212), the Hainan Province Science and Technology Special Fund (no. ZDYF2022XDNY144) and the Hainan Provincial Academician Innovation Platform Project (no. HD-YSZX-202004).

Author contributions

F.K. Y.H. and S.W conceptualized the idea. F.K. S.U. and Y.H. wrote the initial draft. F.K. S.U. Y.H. and S.W. improved the initial draft and prepared the figure. S.W. supervised, reviewed and edited the manuscript. All authors have read and approved the final version of the manuscript.

Conflict of interest statement:

The authors declare that they have no conflict of interest.

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