Abstract
Actin-related protein (ARP2/3) complex is a heteroheptameric protein complex, evolutionary conserved in all eukaryotic organisms. Its conserved role is based on the induction of actin polymerization at the interface between membranes and the cytoplasm. Plant ARP2/3 has been reported to participate in actin reorganization at the plasma membrane during polarized growth of trichomes and at the plasma membrane–endoplasmic reticulum contact sites. Here we demonstrate that individual plant subunits of ARP2/3 fused to fluorescent proteins form motile spot-like structures in the cytoplasm that are associated with peroxisomes in Arabidopsis and tobacco. ARP2/3 is found at the peroxisome periphery and contains the assembled ARP2/3 complex and the WAVE/SCAR complex subunit NAP1. This ARP2/3-positive peroxisomal domain colocalizes with the autophagosome and, under conditions that affect the autophagy, colocalization between ARP2/3 and the autophagosome increases. ARP2/3 subunits co-immunoprecipitate with ATG8f and peroxisome-associated ARP2/3 interact in vivo with the ATG8f marker. Since mutants lacking functional ARP2/3 complex have more peroxisomes than wild type, we suggest that ARP2/3 has a novel role in the process of peroxisome degradation by autophagy, called pexophagy.
| Original language | English |
|---|---|
| Pages (from-to) | 1874-1889 |
| Number of pages | 16 |
| Journal | Nature Plants |
| Volume | 9 |
| Issue number | 11 |
| Early online date | 16 Oct 2023 |
| DOIs | |
| Publication status | E-pub ahead of print - 16 Oct 2023 |
Bibliographical note
Funding Information:Czech Science Foundation project no. 19-10845S (K.S.). Grant Agency of the Charles University nos. 816217 (J.M. and K.S.) and 374522 (B.J. and K.S.). Leverhulme Trust funding RPG-2015-106 (I.S.). Microscopy was performed in the Viničná Microscopy Core Facility co-financed by the Czech-BioImaging large RI project LM2023050. Computational resources were supplied by the project ‘e-Infrastruktura CZ’ (e-INFRA LM2018140) provided within the programme Projects of Large Research, Development, and Innovations Infrastructures. Super-resolution microscopy was performed in the Imaging Facility of the Institute of Experimental Botany ASCR, which was supported by the MEYS CR (Large RI Project LM2023050 Czech-BioImaging). Thanks to K. Harant and P. Talacko (Laboratory of Mass Spectrometry, Charles University, Faculty of Science) for proteomic and mass spectrometric analysis. We thank R. J. O’Connell (INRAE) for ChEC51 and ChEC96 vectors. We also thank M. Fendrych and J. Petrášek for many useful comments and suggestions to the manuscript.
Publisher Copyright:
© 2023, The Author(s), under exclusive licence to Springer Nature Limited.