Autophagy is a major catabolic process whereby autophagosomes deliver cytoplasmic content to the lytic compartment for recycling. Autophagosome formation requires two ubiquitin-like systems conjugating Atg12 with Atg5, and Atg8 with lipid phosphatidylethanolamine (PE), respectively. Genetic suppression of these systems causes autophagy-deficient phenotypes with reduced fitness and longevity. We show that Atg5 and the E1-like enzyme, Atg7, are rate-limiting components of Atg8-PE conjugation in Arabidopsis. Overexpression of ATG5 or ATG7 stimulates Atg8 lipidation, autophagosome formation, and autophagic flux. It also induces transcriptional changes opposite to those observed in atg5 and atg7 mutants, favoring stress resistance and growth. As a result, ATG5- or ATG7-overexpressing plants exhibit increased resistance to necrotrophic pathogens and oxidative stress, delayed aging and enhanced growth, seed set, and seed oil content. This work provides an experimental paradigm and mechanistic insight into genetic stimulation of autophagy in planta and shows its efficiency for improving plant productivity.

• MeSH
• Arabidopsis genetika   fyziologie   MeSH
• Atg5 genetika   metabolismus   MeSH
• autofagie genetika   MeSH
• genetická zdatnost * MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• rodina proteinů Atg8 genetika   metabolismus   MeSH
• signální transdukce genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Caloric restriction mimetics (CRMs) mimic the biochemical effects of nutrient deprivation by reducing lysine acetylation of cellular proteins, thus triggering autophagy. Treatment with the CRM hydroxycitrate, an inhibitor of ATP citrate lyase, induced the depletion of regulatory T cells (which dampen anticancer immunity) from autophagy-competent, but not autophagy-deficient, mutant KRAS-induced lung cancers in mice, thereby improving anticancer immunosurveillance and reducing tumor mass. Short-term fasting or treatment with several chemically unrelated autophagy-inducing CRMs, including hydroxycitrate and spermidine, improved the inhibition of tumor growth by chemotherapy in vivo. This effect was only observed for autophagy-competent tumors, depended on the presence of T lymphocytes, and was accompanied by the depletion of regulatory T cells from the tumor bed.

• MeSH
• Atg5 genetika   MeSH
• autofagie MeSH
• citráty aplikace a dávkování   farmakologie   MeSH
• experimentální nádory dietoterapie   farmakoterapie   imunologie   MeSH
• kalorická restrikce metody   MeSH
• lidé MeSH
• methotrexát aplikace a dávkování   farmakologie   MeSH
• monitorování imunologické MeSH
• mutace MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• protoonkogenní proteiny p21(ras) genetika   MeSH
• regulační T-lymfocyty účinky léků   MeSH
• spermidin aplikace a dávkování   farmakologie   MeSH
• transplantace nádorů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH