DNAJC15 endog. interactome DSP-aided in WT and AFG3L2-KO HeLa cells

Mitochondria dynamically adapt to cellular stress to ensure cell survival. The stress-regulated mitochondrial peptidase OMA1 orchestrates these adaptive responses, which limits mitochondrial fusion and promotes mitochondrial stress signaling and metabolic rewiring. Here, we show that cellular stress adaptation involves OMA1-mediated regulation of mitochondrial protein import and OXPHOS biogenesis. OMA1 cleaves the mitochondrial chaperone DNAJC15 and promotes its degradation by the m-AAA protease AFG3L2. Loss of DNAJC15 impairs mitochondrial protein import and restricts OXPHOS biogenesis under conditions of mitochondrial dysfunction. Non-imported mitochondrial preproteins accumulate at the endoplasmic reticulum inducing an unfolded protein response. Our results demonstrate stress-dependent changes in mitochondrial protein import as part of the OMA1-mediated mitochondrial stress response and highlight the interdependence of proteostasis regulation between different organelles. In this part of the project, the interactome of the short-JC15 (cleaved by OMA1) was explored. In AFG3L2 there is an increased accumulation of s-JC15. The endougenously JC15 was pulled down. DSP was used to cross-link proteins prior to pulldown. The internal ID is RzrI9DIje2. Due to character restrictions, the raw files had to be renamed for upload replacing (--) to KO and (++) to WT.