The CLP and PREP protease systems coordinate maturation and degradation of the chloroplast proteome in Arabidopsis thaliana

New Phytologist, Год журнала: 2022, Номер 236(4), С. 1339 - 1357

Опубликована: Авг. 10, 2022

A network of peptidases governs proteostasis in plant chloroplasts and mitochondria. This study reveals strong genetic functional interactions Arabidopsis between the chloroplast stromal CLP chaperone-protease system PREP1,2 peptidases, which are dually localized to stroma mitochondrial matrix. Higher order mutants defective or PREP proteins were generated analyzed by quantitative proteomics N-terminal (terminal amine isotopic labeling substrates (TAILS)). Strong synergistic observed protease (clpr1-2, clpr2-1, clpc1-1, clpt1, clpt2) both homologs (prep1, prep2) resulting embryo lethality growth developmental phenotypes. Synergistic even when only one was lacking, suggesting that PREP1 PREP2 have divergent substrates. Proteome phenotypes driven loss capacity, with little impact from peptidases. Chloroplast proteomes showed many nuclear encoded alternatively processed N-termini prep1prep2, clpt1clpt2 prep1prep2clpt1clpt2. Loss capacity interferes processing peptidase (SPP) activity due folding stress low levels accumulated cleaved cTP fragments. proteolysis cTPs is complemented unknown proteases. model for within a hierarchical proposed.

Язык: Английский

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Selective autophagy: adding precision in plant immunity

Essays in Biochemistry, Год журнала: 2022, Номер 66(2), С. 189 - 206

Опубликована: Июнь 6, 2022

Plant immunity is antagonized by pathogenic effectors during interactions with bacteria, viruses or oomycetes. These target core plant processes to promote infection. One such process autophagy, a conserved proteolytic pathway involved in ensuring cellular homeostasis. It involves the formation of autophagosomes around proteins destined for autophagic degradation. Many components from organelles, aggregates, inactive misfolded have been found be degraded via autophagy. Increasing evidence points high degree specificity targeting these components, strengthening idea selective Selective autophagy receptors bridge gap between and forming autophagosome. To achieve this, are able recognize specifically their ubiquitin-dependent -independent manner, bind ATG8 canonical non-canonical ATG8-interacting motifs. Some also shown require oligomerization function We summarize recent advances role highlight NBR1 as key player. However, not many receptors, especially those functioning immunity, characterized plants. propose an silico approach identify novel screening Arabidopsis proteome containing features theoretically needed receptor. corroborate data, transcript levels immune response investigated using public databases. further perspectives applications introduced immunity-related studies, demonstrating its importance research.

Язык: Английский

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Autophagy during maize endosperm development dampens oxidative stress and promotes mitochondrial clearance

PLANT PHYSIOLOGY, Год журнала: 2023, Номер 193(2), С. 1395 - 1415

Опубликована: Июнь 19, 2023

Abstract The selective turnover of macromolecules by autophagy provides a critical homeostatic mechanism for recycling cellular constituents and removing superfluous damaged organelles, membranes, proteins. To better understand how impacts seed maturation nutrient storage, we studied maize (Zea mays) endosperm in its early middle developmental stages via an integrated multiomic approach using mutants impacting the core macroautophagy factor AUTOPHAGY (ATG)-12 required autophagosome assembly. Surprisingly, mutant these windows accumulated normal amounts starch Zein storage However, tissue acquired substantially altered metabolome, especially compounds related to oxidative stress sulfur metabolism, including increases cystine, dehydroascorbate, cys-glutathione disulfide, glucarate, galactarate, decreases peroxide antioxidant glutathione. While changes associated transcriptome were mild, proteome was strongly atg12 endosperm, increased levels mitochondrial proteins without concomitant increase mRNA abundances. Although fewer mitochondria seen cytologically, heightened number appeared dysfunctional based on accumulation dilated cristae, consistent with attenuated mitophagy. Collectively, our results confirm that plays minor role during development but likely helps protect against clears unneeded/dysfunctional maturation.

Язык: Английский

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FRIENDLY is required for efficient dark-induced mitophagy and controlled senescence in Arabidopsis

Free Radical Biology and Medicine, Год журнала: 2023, Номер 204, С. 1 - 7

Опубликована: Апрель 19, 2023

Mitochondria play essential roles in plant metabolism, supporting both development and stress responses. To maintain a healthy pool of mitochondria, several quality control systems are place. Selected degradation mitochondria by autophagy -mitophagy- has been extensively studied yeast animals, but information on mitophagy components plants is limited. The 'Friendly Mitochondria' (FRIENDLY; FMT) protein, homologous to 'clustered protein homolog' CLU was recently suggested mediate depolarized mitochondria. In this study, we evaluated the role FMT carbon starvation- dark senescence-induced Arabidopsis. Using flux assays, show that loss results decreased during dark-induced senescence. Mitophagy induced inhibition Target Rapamycin (TOR) signalling also partially impaired fmt mutants. mostly localised cytosol, darkness redistributed into speckles, some which associate with Fmt mutants were initially identified for their abnormal mitochondrial morphology, often forming clusters. We found senescence strongly increases number size clusters agreement mitophagy, accelerated phenotypes comparable 11 (atg11) mutants, less prominent than atg5 Furthermore, prevents excessive cell death hydrogen peroxide production, supports greening etiolated seedlings. Our findings thus indicate contributes provide evidence required controlled prevention death. propose mediates efficient preventing clustering, thereby allowing be captured more effectively autophagosomes, rather acting as direct receptor.

Язык: Английский

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Mitophagy in plants

Biochimica et Biophysica Acta (BBA) - General Subjects, Год журнала: 2021, Номер 1865(8), С. 129916 - 129916

Опубликована: Апрель 28, 2021

Язык: Английский

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