Institute of Biology II, Chair of Molecular Plant Physiology, University of Freiburg, 79104 Freiburg, Germany.
Center for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
Proc Natl Acad Sci U S A. 2023 Aug;120(31):e2218865120. doi: 10.1073/pnas.2218865120. Epub 2023 Jul 24.
Extreme environmental conditions eventually limit plant growth [J. R. Dinneny, , 1-19 (2019), N. Gigli-Bisceglia, C. Testerink, , 102120 (2021)]. Here, we reveal a mechanism that enables multiple external cues to get integrated into auxin-dependent growth programs in . Our forward genetics approach on dark-grown hypocotyls uncovered that an imbalance in membrane lipids enhances the protein abundance of PIN-LIKES (PILS) [E. Barbez , , 119 (2012)] auxin transport facilitators at the endoplasmic reticulum (ER), which thereby limits nuclear auxin signaling and growth rates. We show that this subcellular response relates to ER stress signaling, which directly impacts PILS protein turnover in a tissue-dependent manner. This mechanism allows PILS proteins to integrate environmental input with phytohormone auxin signaling, contributing to stress-induced growth adaptation in plants.
极端环境条件最终会限制植物的生长[J. R. Dinneny， ，1-19 (2019)，N. Gigli-Bisceglia，C. Testerink， ，102120 (2021)]。在这里，我们揭示了一种机制，使多种外部线索能够整合到生长素依赖的生长程序中。我们对黑暗中生长的下胚轴进行正向遗传学研究，发现膜脂失衡会增强质膜内在蛋白（PIN-LIKES，PILS）[E. Barbez ， ，119 (2012)]生长素运输促进因子在内质网上的蛋白丰度，从而限制核内生长素信号和生长速率。我们表明，这种亚细胞反应与内质网应激信号有关，该信号直接以组织依赖的方式影响 PILS 蛋白的周转。这种机制使 PILS 蛋白能够将环境输入与植物激素生长素信号整合在一起，有助于植物在应激诱导下的生长适应。
