Language

English

Publication Date

7-15-2024

Journal

Journal of Cell Science

DOI

10.1242/jcs.261268

PMID

38896010

PMCID

PMC11304411

PubMedCentral® Posted Date

7-26-2024

PubMedCentral® Full Text Version

Post-print

Abstract

Mitochondria, which act as sensors of metabolic homeostasis and metabolite signaling, form a dynamic intracellular network that continuously changes shape, size and localization to respond to localized cellular energy demands. Mitochondrial dynamics and function depend on interactions with the F-actin cytoskeleton that are poorly understood. Here, we show that SET domain protein 3 (SETD3), a recently described actin histidine methyltransferase, directly methylates actin at histidine-73 and enhances F-actin polymerization on mitochondria. SETD3 is a mechano-sensitive enzyme that is localized on the outer mitochondrial membrane and promotes actin polymerization around mitochondria. SETD3 loss of function leads to diminished F-actin around mitochondria and a decrease in mitochondrial branch length, branch number and mitochondrial movement. Our functional analysis revealed that SETD3 is required for oxidative phosphorylation, and mitochondrial complex I assembly and function. Our data further indicate that SETD3 regulates F-actin formation around mitochondria and is essential for maintaining mitochondrial morphology, movement and function. Finally, we discovered that SETD3 levels are regulated by extracellular matrix (ECM) stiffness and regulate mitochondrial shape in response to changes in ECM stiffness. These findings provide new insight into the mechanism for F-actin polymerization around mitochondria.

Keywords

Actins, Humans, Mitochondria, Mitochondrial Dynamics, Methylation, Histidine, Extracellular Matrix, Methyltransferases, Animals, HeLa Cells, Histone Methyltransferases, Mitochondrial dynamics, Cytoskeleton, Mechanotransduction, Post-translational modifications

Published Open-Access

yes

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.