Drosophila NFS1.R77 is required for differential protein complex composition

ABSTRACT: S-adenosylmethionine (SAM) is the principle biological methyl group donor for a diverse range of substrates. It is synthesised in the cytosolic methionine cycle and shuttled throughout the cell. The mitochondrial SAM (mitoSAM) pool depends on import through the inner-membrane SAMC and supports the maturation of metabolites and mitochondrial RNAs. We demonstrated that mitoSAM differentially effects mitochondrial function. Metabolite and iron-sulphur cluster biosynthesis are disrupted due to acutely decreased methylation potential, while prolonged mitoSAM deficiency affects fly longevity and OXPHOS stability. We developed a fly-compatible SILAC labelling technique and mapped mitochondrial protein methylation sites. Based on a novel mono-methylation on the DmR77 (HsR72) of the cysteine desulfurase NFS1 our data indicates that methylation can be used to regulate differential protein complex composition in mitochondria on the basis of immunoprecipitation data in this submission. While iron-sulphur cluster containing proteins enriched with Drosophila Nfs1.R77F that mimics a constitutively methylated Nfs1, the iron sequestering protein Fer1HCH bound stronger to Nfs1.R77K that resembles absence of methylation. Our results define the critical role of cytoplasmic SAM production for mitochondrial methylation events and highlight the indirect effect of one-carbon metabolism on cellular bioenergetics.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Drosophila Melanogaster (fruit Fly)

TISSUE(S): Larva

SUBMITTER: Florian Schober  

LAB HEAD: Anna Wredenberg

PROVIDER: PXD019551 | Pride | 2021-02-22

REPOSITORIES: Pride