How coat proteins shape autophagy in plant cells DOI
Taijoon Chung, Ye Eun Choi, Kyoungjun Song

et al.

PLANT PHYSIOLOGY, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 11, 2024

Abstract Autophagy is a membrane trafficking pathway through which eukaryotic cells target their own cytoplasmic constituents for degradation in the lytic compartment. Proper biogenesis of autophagic organelles requires conserved set autophagy-related (ATG) proteins and interacting factors, such as signalling phospholipid phosphatidylinositol 3-phosphate (PI3P) coat complex II (COPII). The COPII machinery, was originally identified involved formation vesicles budding from endoplasmic reticulum, contributes to initiation yeast, metazoan, plant cells; however, exact mechanisms remain elusive. Recent studies using model species Arabidopsis thaliana have revealed that plant-specific PI3P effectors are autophagy. effector FYVE2 interacts with ATG18 components, indicating an additional role machinery later stages autophagosome biogenesis. In this Update, we examined recent research on proposed working models functions autophagy, including its potential roles stabilizing curvature sealing phagophore.

Language: Английский

Interplay between autophagy and proteasome during protein turnover DOI Creative Commons
Margot Raffeiner, Shanshuo Zhu, Manuel González‐Fuente

et al.

Trends in Plant Science, Journal Year: 2023, Volume and Issue: 28(6), P. 698 - 714

Published: Feb. 20, 2023

Protein homeostasis is epitomized by an equilibrium between protein biosynthesis and degradation: the 'life death' of proteins. Approximately one-third newly synthesized proteins are degraded. As such, turnover required to maintain cellular integrity survival. Autophagy ubiquitin–proteasome system (UPS) two principal degradation pathways in eukaryotes. Both orchestrate many processes during development upon environmental stimuli. Ubiquitination targets used as a 'death' signal both processes. Recent findings revealed direct functional link pathways. Here, we summarize key field homeostasis, with emphasis on crosstalk machineries how it decided which pathway facilitates target degradation.

Language: Английский

Citations

52
The plant unique ESCRT component FREE1 regulates autophagosome closure DOI Creative Commons
Yonglun Zeng, Baiying Li, Shuxian Huang

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 30, 2023

Abstract The energy sensor AMP-activated protein kinase (AMPK) can activate autophagy when cellular production becomes compromised. However, the degree to which nutrient sensing impinges on autophagosome closure remains unknown. Here, we provide mechanism underlying a plant unique FREE1, upon autophagy-induced SnRK1α1-mediated phosphorylation, functions as linkage between ATG conjugation system and ESCRT machinery regulate deprivation. Using high-resolution microscopy, 3D-electron tomography, protease protection assay, showed that unclosed autophagosomes accumulated in free1 mutants. Proteomic, biochemical analysis revealed mechanistic connection FREE1 system/ESCRT-III complex regulating closure. Mass spectrometry evolutionary conserved SnRK1α1 phosphorylates recruits it promote Mutagenesis of phosphorylation site caused failure. Our findings unveil how pathways maintain homeostasis.

Language: Английский

Citations

34
Plant Extracellular Vesicles: Current Landscape and Future Directions DOI Creative Commons
Alfredo Ambrosone, Ani Barbulova,

Elisa Cappetta

et al.

Plants, Journal Year: 2023, Volume and Issue: 12(24), P. 4141 - 4141

Published: Dec. 12, 2023

Plant cells secrete membrane-enclosed micrometer- and nanometer-sized vesicles that, similarly to the extracellular (EVs) released by mammalian or bacterial cells, carry a complex molecular cargo of proteins, nucleic acids, lipids, primary secondary metabolites. While it is technically complicated isolate EVs from whole plants their tissues, in vitro plant cell cultures provide excellent model systems for study. have been isolated conditioned culture media cell, pollen, hairy root, protoplast cultures, recent studies gathered important structural biological data that framework decipher physiological roles unveil previously unacknowledged links diverse functions. The function seems be secretion underlies growth morphogenesis, wall composition, cell-cell communication processes. Besides functions, may participate defence mechanisms against different pathogens, including fungi, viruses, bacteria. Whereas edible medicinal-plant-derived nanovesicles homogenised materials ex vivo are widely studied exploited, today, EV research still its infancy. This review, first time, highlights sources used EVs, together with investigate cargo, pinpoints possible role as mediators plant-pathogen interactions, which contribute opening up new scenarios agricultural applications, biotechnology, innovative strategies disease management.

Language: Английский

Citations

25
ATG8ylation of vacuolar membrane protects plants against cell wall damage DOI Creative Commons
Jose Julian, Peng Gao, Alessia Del Chiaro

et al.

Nature Plants, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Abstract Vacuoles are essential for cellular metabolism and growth the maintenance of internal turgor pressure. They sequester lytic enzymes, ions secondary metabolites that, if leaked into cytosol, could lead to cell death. Despite their pivotal roles, quality control pathways that safeguard vacuolar integrity have remained elusive in plants. Here we describe a conserved pathway is activated upon wall damage turgor-pressure-dependent manner. Cell perturbations induce distinct modification—ATG8ylation—on membrane (tonoplast) regulated by V-ATPase ATG8 conjugation machinery. Genetic disruption tonoplast ATG8ylation impairs integrity, leading Together, our findings reveal homeostatic preserves damage.

Language: Английский

Citations

1
Protein degrons and degradation: Exploring substrate recognition and pathway selection in plants DOI

Erika Isono,

Jianming Li, Pablo Pulido

et al.

The Plant Cell, Journal Year: 2024, Volume and Issue: 36(9), P. 3074 - 3098

Published: May 3, 2024

Proteome composition is dynamic and influenced by many internal external cues, including developmental signals, light availability, or environmental stresses. Protein degradation, in synergy with protein biosynthesis, allows cells to respond various stimuli adapt reshaping the proteome. degradation mediates final irreversible disassembly of proteins, which important for quality control eliminate misfolded damaged as well entire organelles. Consequently, it contributes cell resilience buffering against organellar damage caused Moreover, plays roles signaling, transcriptional translational events. The intricate task recognizing specific proteins achieved specialized systems that are tailored substrate's physicochemical properties subcellular localization. These recognize diverse substrate cues collectively referred "degrons," can assume a range configurations. They molecular surfaces recognized E3 ligases ubiquitin-proteasome system but also be considered general features other systems, autophagy even proteases. Here we provide an overview newest developments field, delving into processes recognition elucidating pathways through they recruited degradation.

Language: Английский

Citations

7
Arabidopsis CaLB1 undergoes phase separation with the ESCRT protein ALIX and modulates autophagosome maturation DOI Creative Commons
Niccolò Mosesso,

Niharika Savant Lerner,

Tobias Bläske

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: June 19, 2024

Abstract Autophagy is relevant for diverse processes in eukaryotic cells, making its regulation of fundamental importance. The formation and maturation autophagosomes require a complex choreography numerous factors. endosomal sorting required transport (ESCRT) implicated the final step autophagosomal by sealing phagophore membrane. ESCRT-III components were shown to mediate membrane scission forming filaments that interact with cellular membranes. However, molecular mechanisms underlying recruitment ESCRTs non-endosomal membranes remain largely unknown. Here we focus on ESCRT-associated protein ALG2-interacting X (ALIX) identify Ca 2+ -dependent lipid binding 1 (CaLB1) as interactor. Our findings demonstrate CaLB1 interacts AUTOPHAGY8 (ATG8) PI(3)P, phospholipid found Moreover, ALIX localize ATG8 upon salt treatment assemble together into condensates. depletion impacts salt-induced leads reduced delivery vacuole. Here, propose crucial role augmenting phase separation ALIX, facilitating site closure thereby ensuring efficient autophagosomes.

Language: Английский

Citations

7
Arabidopsis AUTOPHAGY-RELATED2 is essential for ATG18a and ATG9 trafficking during autophagosome closure DOI
Mengqian Luo, Kai Ching Law, Yilin He

et al.

PLANT PHYSIOLOGY, Journal Year: 2023, Volume and Issue: 193(1), P. 304 - 321

Published: May 17, 2023

Abstract As a fundamental metabolic pathway, autophagy plays important roles in plant growth and development, particularly under stress conditions. A set of autophagy-related (ATG) proteins is recruited for the formation double-membrane autophagosome. Among them, essential ATG2, ATG18, ATG9 have been well established via genetic analysis; however, underlying molecular mechanism ATG2 autophagosome remains poorly understood. In this study, we focused on specific role trafficking ATG18a during Arabidopsis (Arabidopsis thaliana). Under normal conditions, YFP-ATG18a are partially localized late endosomes translocated to ATG8e-labeled autophagosomes upon autophagic induction. Real-time imaging analysis revealed sequential recruitment phagophore membrane, showing that specifically decorated closing edges finally disassociated from completed However, absence most arrested autophagosomal membranes. Ultrastructural 3D tomography showed unclosed structures accumulated atg2 mutant, displaying direct connections with endoplasmic reticulum membrane vesicular structures. Dynamic vesicles suggested depletion also affects association between membrane. Furthermore, using interaction analysis, mapped relationship ATG18a, implying possible recruiting Our findings unveil coordinating mediate closure Arabidopsis.

Language: Английский

Citations

15
Recent advances in cellular degradation and nuclear control of leaf senescence DOI
Lei Pei, Fei Yu, Xiayan Liu

et al.

Journal of Experimental Botany, Journal Year: 2023, Volume and Issue: 74(18), P. 5472 - 5486

Published: July 15, 2023

Abstract Senescence is the final stage of plant growth and development, a highly regulated process at molecular, cellular, organismal levels. When triggered by age, hormonal, or environmental cues, plants actively adjust their metabolism gene expression to execute progression senescence. Regulation senescence vital for reallocation nutrients sink organs, ensure reproductive success adaptations stresses. Identification characterization hallmarks leaf are great importance understanding molecular regulatory mechanisms senescence, breeding future crops with more desirable traits. Tremendous progress has been made in elucidating genetic network underpinning metabolic cellular changes In this review, we focus on three – chlorophyll chloroplast degradation, loss proteostasis, activation senescence-associated genes (SAGs), discuss recent findings players crosstalk pathways.

Language: Английский

Citations

13
Autophagosome biogenesis and organelle homeostasis in plant cells DOI

Xiaohong Zhuang,

Baiying Li, Liwen Jiang

et al.

The Plant Cell, Journal Year: 2024, Volume and Issue: 36(9), P. 3009 - 3024

Published: March 27, 2024

Autophagy is one of the major highly inducible degradation processes in response to plant developmental and environmental signals. In different stimuli, cellular materials, including proteins organelles, can be sequestered into a double membrane autophagosome structure either selectively or nonselectively. The formation an as well its delivery vacuole involves complex dynamic processes. identification characterization conserved autophagy-related (ATG) their related regulators have greatly advanced our understanding molecular mechanism underlying biogenesis function cells. Autophagosome tightly regulated by coordination multiple ATG non-ATG selective cargo recruitment. This review updates current knowledge biogenesis, with special emphasis on core machinery that drives autophagosome-organelle interactions under abiotic stress conditions.

Language: Английский

Citations

5
A RabGAP negatively regulates plant autophagy and immune trafficking DOI Creative Commons
Enoch Lok Him Yuen, Alexandre Y Leary, Marion Clavel

et al.

Current Biology, Journal Year: 2024, Volume and Issue: 34(10), P. 2049 - 2065.e6

Published: April 26, 2024

Plants rely on autophagy and membrane trafficking to tolerate stress, combat infections, maintain cellular homeostasis. However, the molecular interplay between is poorly understood. Using an AI-assisted approach, we identified Rab3GAP-like (Rab3GAPL) as a key node that controls plant negatively. Rab3GAPL suppresses by binding ATG8, core adaptor, deactivating Rab8a, small GTPase essential for autophagosome formation defense-related secretion. reduces autophagic flux in three model species, suggesting its negative regulatory role conserved land plants. Beyond regulation, modulates focal immunity against oomycete pathogen Phytophthora infestans preventing Altogether, our results suggest acts rheostat coordinate secretion restraining Rab8a-mediated trafficking. This unprecedented RabGAP-Rab pair ATG8 sheds new light intricate transport mechanisms underlying immunity.

Language: Английский

Citations

5