INTEGRATED MULTI-OMICS ANALYSES OF MAIZE REVEAL ROLES FOR AUTOPHAGIC DURING FIXED CARBON STARVATION

ABSTRACT: The turnover of cytoplasmic material via autophagic encapsulation and delivery to vacuoles is essential for recycling cellular constituents, especially under nutrient-limiting conditions. To determine how cells/tissues rely on autophagy, we applied in-depth multi-omic analyses to study maize (Zea mays) autophagy mutants grown after fixed carbon starvation. Surprisingly, broad alterations in the leaf metabolome were evident in plants missing the core autophagy component ATG12 even without stress, particularly affecting products of lipid turnover and secondary metabolites, which were underpinned by substantial changes in the transcriptome and/or proteome. Cross-comparison of mRNA and protein abundances allowed for the identification of organelles, protein complexes, and individual proteins targeted for selective autophagic clearance, and revealed several processes controlled by this catabolism. Fixed carbon starvation induced the proteins involved in alternative respiration together with the upregulation of various alternative catabolic processes. Collectively, we describe a facile proteomic strategy to survey autophagic substrates, and show that autophagy has a greater than expected influence in sculpting plant proteomes and membranes both before and during nitrogen stress.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Zea Mays (maize)

TISSUE(S): Plant Cell, Leaf

SUBMITTER: Fionn McLoughlin  

LAB HEAD: Richard D Vierstra

PROVIDER: PXD017077 | Pride | 2020-07-15

REPOSITORIES: Pride