MRNA trafficking directs cell-size-scaling of mitochondria distribution and function.

ABSTRACT: The subcellular positioning of organelles is critical to their function and is dynamically adapted to changes in cell morphology. Yet, how cells sense shifts in their dimensions and redistribute organelles accordingly remains unclear. Here we reveal that cell-size-scaling of mitochondria distribution and function is directed by polarised trafficking of mRNAs. We identify a 29 bp 3'UTR motif in mRNA encoding TRAK2, a key determinant of mitochondria retrograde transport, that promotes cell-size-dependent targeting of TRAK2 mRNA to distal sites of cell protrusions. Cell-size-scaled mRNA polarisation in turn scales mitochondria distribution by defining the precise site of TRAK2-MIRO1 retrograde transport complex assembly. Consequently, 3'UTR motif excision perturbs size-regulated transport and

SUBMITTER: Bradbury JJ 

PROVIDER: S-EPMC12313994 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature