Air channels create a directional light signal to regulate hypocotyl phototropism

• 成果类型: Article
• 署名作者: Nawkar, Ganesh M.; Legris, Martina; Goyal, Anupama; Schmid-Siegert, Emanuel; Fleury, Jeremy; Mucciolo, Antonio; De Bellis, Damien; Trevisan, Martine; Schueler, Andreas; Fankhauser, Christian
• 署名单位: University of Lausanne; University of Lausanne; Swiss Institute of Bioinformatics; University of Lausanne; University of Lausanne; Savitribai Phule Pune University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8802
• DOI: 10.1126/science.adh9384
• 发表日期: 2023-11-24
• 页码: 935-940
• 关键词: positive phototropism; intercellular spaces; gene activity; gas space; arabidopsis; expression; perception; mutations; promoter; protein

摘要

In plants, light direction is perceived by the phototropin photoreceptors, which trigger directional growth responses known as phototropism. The formation of a phototropin activation gradient across a photosensitive organ initiates this response. However, the optical tissue properties that functionally contribute to phototropism remain unclear. In this work, we show that intercellular air channels limit light transmittance through various organs in several species. Air channels enhance light scattering in Arabidopsis hypocotyls, thereby steepening the light gradient. This is required for an efficient phototropic response in Arabidopsis and Brassica. We identified an embryonically expressed ABC transporter required for the presence of air channels in seedlings and a structure surrounding them. Our work provides insights into intercellular air space development or maintenance and identifies a mechanism of directional light sensing in plants.