Modification of Non-photochemical Quenching Pathways in the C 4 Model Plant Setaria viridis Revealed Shared and Unique Photoprotection Mechanisms as Compared to C 3 Plants

作者：Grace Milburn, Chris Morris, Eileen Kosola, Dhruv Patel‐Tupper, Jian Liu, Dominique H. Pham, Lucia Acosta‐Gamboa, William D. Stone, Sarah A. Pardi, Kylee Hillman, William McHargue, Eric Becker, Xiaojun Kang, Josh Sumner, Catherine Bailey, Peter Thielen, Georg Jander, Cade N. Kane, Scott A. M. McAdam, Thomas J. Lawton, Dmitri A. Nusinow, Feng Zhang, Michael A. Gore, Jianlin Cheng, Krishna Niyogi, Ru Zhang · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2025 · DOI：10.1101/2025.01.12.632622 · 被引用次数：4 · 研究领域：Photosynthetic Processes and Mechanisms、Light effects on plants、Algal biology and biofuel production

Summary Light is essential for photosynthesis; however, excess light can increase the accumulation of photoinhibitory reactive oxygen species that reduce photosynthetic efficiency. Plants have evolved photoprotective non-photochemical quenching (NPQ) pathways to dissipate excess light energy. In tobacco and soybean (C 3 plants), overexpression of three NPQ genes, violaxanthin de-epoxidas e ( V DE), Photosystem II Subunit S ( P sbS), and zeaxanthin epoxidase ( Z EP), hereafter VPZ, resulted in faster NPQ induction and relaxation kinetics, and increased crop yields in field conditions. NPQ is well-studied in C 3 plants; however, NPQ and the translatability of the VPZ approach in C 4 plants is poorly understood. The green foxtail Setaria viridis is an excellent model to study photosynthesis and photoprotection in C 4 plants. To understand the regulation of NPQ and photosynthesis in C 4 plants, we performed transient overexpression in Setaria protoplasts and generated (and employed) stable transgenic Setaria plants overexpressing one of the three Arabidopsis NPQ genes or all three NPQ genes (AtVPZ lines). Overexpressing (OE) AtVDE and AtZEP in Setaria produced similar results as in C 3 plants, with increased or reduced zeaxanthin (thus NPQ), respectively. However, overexpressing AtPsbS appeared to be challenging in Setaria, with largely reduced NPQ in protoplasts and under-represented homozygous AtPsbS-OE lines, potentially due to competitive and tight heterodimerization of AtPsb...