Proteomic Analysis Infers Optimized ATP-Production in Guard Cell Mitochondria

Authored by

Noah Ditz, Markus Niehaus, Nieves Medina Escobar, Marco Herde, Holger Eubel

Abstract

Guard cells are highly specialised leaf cells which regulate leaf transpiration and carbon fixation. As such, they are instrumental in balancing water use efficiency and photosynthetic activity. This unique function of guard cells requires them to quickly accumulate solutes for ATP-dependent stomatal opening, but how this affects mitochondrial energy metabolism remains elusive. Using cell-type-specific affinity purification of Arabidopsis thaliana guard cell and mesophyll cell mitochondria, we aim at unravelling the enzymatic configuration of guard cell mitochondria in order to provide a first glance at the metabolic properties of these specialised organelles. When compared to their mesophyll cell counterparts, the use of alternative substrates for NADH production, a shift away from non-proton pumping respiratory enzymes, and a lower NADH re-oxidation rate suggest a specialised mode of ATP production in guard cell mitochondria. In addition, a lowered abundance of the mitochondrial import machinery also indirectly implies lower protein turnover rates in these organelles.

Details

Organisation(s)
Institute of Plant Genetics
Institute of Plant Nutrition
Type
Article
Journal
Physiologia plantarum
Volume
177
ISSN
0031-9317
Publication date
26.09.2025
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Physiology, Genetics, Plant Science, Cell Biology
Electronic version(s)
https://doi.org/10.1111/ppl.70529 (Access: Open )