AP3M harbors actin filament binding activity that is crucial for vacuole morphology and stomatal closure in Arabidopsis.
Wenna Zheng, Yuxiang Jiang, Xiangfeng Wang, Shanjin Huang, Ming Yuan, Yan Guo
Proceedings of the National Academy of Sciences of the United States of America | Proceedings of the National Academy of Sciences | Published : 2019
Stomatal movement is essential for plant growth. This process is precisely regulated by various cellular activities in guard cells. F-actin dynamics and vacuole morphology are both involved in stomatal movement. The sorting of cargoes by clathrin adaptor protein (AP) complexes from the Golgi to the vacuole is critical for establishing a normal vacuole morphology. In this study, we demonstrate that the medium subunit of the AP3 complex (AP3M) binds to and severs actin filaments in vitro and that it participates in the sorting of cargoes (such as the sucrose exporter SUC4) to the tonoplast, and thereby regulates stomatal closure in Arabidopsis thaliana Defects in AP3 or SUC4 led to more rapid ..View full abstract