UV-B irradiation-activated E3 ligase GmILPA1 modulates gibberellin catabolism to increase plant height in soybean

Abstract

Plant height is a key agronomic trait that affects yield and is controlled by both phytohormone gibberellin (GA) and ultraviolet-B (UV-B) irradiation. However, whether and how plant height is modulated by UV-B-mediated changes in GA metabolism are not well understood. It has not been reported that the E3 ubiquitin ligase Anaphase Promoting Complex/Cyclosome (APC/C) is involved in the regulation of plant growth in response to environmental factors. We perform a forward genetic screen in soybean and find that a mutation in Glycine max Increased Leaf Petiole Angle1 (GmILPA1), encoding a subunit of the APC/C, lead to dwarfism under UV-B irradiation. UV-B promotes the accumulation of GmILPA1, which ubiquitinate the GA catabolic enzyme GA2 OXIDASE-like (GmGA2ox-like), resulting in its degradation in a UV-B-dependent manner. Another E3 ligase, GmUBL1, also ubiquitinate GmGA2ox-like and enhance the GmILPA1-mediated degradation of GmGA2ox-like, which suggest that GmILPA1-GmGA2ox-like module counteract the UV-B-mediated reduction of bioactive GAs. We also determine that GmILPA1 is a target of selection during soybean domestication and breeding. The deletion (Indel-665) in the promoter might facilitate the adaptation of soybean to high UV-B irradiation. This study indicates that an evolutionary GmILPA1 variant has the capability to develop ideal plant architecture with soybean cultivars.

Soybean reduced internode 1 determines internode length and improves grain yield at dense planting

“…Reduced plant height and lodging tolerance are critical for dense planting 9 . Gibberellins (GA) are a class of plant-growth hormones and well-known determinants of plant height.…”

QTL mapping for plant height and ear height using bi-parental immortalized heterozygous populations in maize

“…Additionally, Zm00001d011108 encodes E3 ubiquitin-protein ligase ORTHRUS 2. The E3 ligase encoded by GmlPA1 has been confirmed to play a role in regulating the PH of soybean ( Sun et al., 2023 ). These findings demonstrate the utility of QTL mapping for complex quantitative traits using multiple populations with diverse genetic backgrounds, and the related candidate genes can be identified rapidly using previously published multi-omic datasets.…”