biostudies-literatureDel Chiaro AAustrian Science Fund FWFDeutsche ForschungsgemeinschaftEuropean Research CouncilAustrian Academy of SciencesVienna Science and Technology FundHORIZON EUROPE Marie Sklodowska-Curie Actionsjcs263803https://www.ebi.ac.uk/biostudies/studies/S-EPMC12450472biostudies-literatureUnknown138(17)Autophagy sustains cellular health by recycling damaged or excess components through autophagosomes. Autophagy is mediated by conserved ATG proteins, among which the ubiquitin-like ATG8 proteins play a central role by linking cargo to the growing autophagosomes. Unlike most ATG proteins, the ATG8 gene family is significantly expanded in vascular plants, but its functional specialization remains poorly understood. Using transcriptional and translational reporters in Arabidopsis thaliana, we revealed that ATG8 isoforms are differentially expressed across tissues and form distinct autophagosomes. To explore ATG8 specialization, we generated the nonuple Δatg8 mutant, lacking all nine ATG8 isoforms. The mutant displayed hypersensitivity to carbon and nitrogen starvation, coupled with defects inJournal of cell scienceAn A. thaliana mutant lacking all nine ATG8 isoforms provides genetic evidence for functional specialization of ATG8 in plants.PMC12450472P34944LS21-09LS21-009847548Heisenberg ProfessorshipLS17-47LS17-047SFB F79P32355101043370DOC 111Kang BHPapareddy RKBerger FGrujic NGao PLofke CGruetzner RDel Chiaro ABhattacharya AMarillonnet SBourguet PMa JDagdas YZhao JfalseAn A. thaliana mutant lacking all nine ATG8 isoforms provides genetic evidence for functional specialization of ATG8 in plants.Autophagy sustains cellular health by recycling damaged or excess components through autophagosomes. Autophagy is mediated by conserved ATG proteins, among which the ubiquitin-like ATG8 proteins play a central role by linking cargo to the growing autophagosomes. Unlike most ATG proteins, the ATG8 gene family is significantly expanded in vascular plants, but its functional specialization remains poorly understood. Using transcriptional and translational reporters in Arabidopsis thaliana, we revealed that ATG8 isoforms are differentially expressed across tissues and form distinct autophagosomes. To explore ATG8 specialization, we generated the nonuple Δatg8 mutant, lacking all nine ATG8 isoforms. The mutant displayed hypersensitivity to carbon and nitrogen starvation, coupled with defects in2025-01-01T00:00:00Z2025 Sep2026-06-03T17:30:35.274Z2026-04-30T03:07:22.026ZS-EPMC124504724081426110.1242/jcs.263803