Differentiation of young and replicatively aged mouse C2C12 muscle cells

ABSTRACT: Age-related impairments in myoblast differentiation may contribute to reductions in muscle function in older adults but the underlying proteostasis processes are not well understood. We investigated young (P6-10) and replicatively aged (P48-50) C2C12 myoblast cultures during early (0h-24h) and late (72h-96h) stages of differentiation using deuterium oxide (D2O) labelling and mass spectrometry. The absolute dynamic profiling technique for proteomics (Proteo-ADPT) was used to quantify the absolute rates of abundance change, synthesis and degradation of individual proteins. Proteo-ADPT encompassed 116 proteins and 74 proteins exhibited significantly (P<0.05, FDR <5 %) different changes in abundance between young and aged cells at early and later periods of differentiation. Young cells exhibited a steady pattern of growth, protein accretion and fusion, whereas aged cells failed to gain protein mass or undergo fusion during later differentiation. Maturation of the proteome was retarded in aged myoblasts at the onset of differentiation, but the proteome appeared to ‘catch up’ with the young cells during the early differentiation period. However, this ‘catch up’ process in aged cells was not accomplished by higher levels of protein synthesis. Instead, a lower level of protein degradation in aged cells was responsible for the elevated gains in protein abundance. Our novel data point to a loss of proteome quality as a precursor to the lack of fusion of aged myoblasts and highlights dysregulation of protein degradation, particularly of ribosomal and chaperone proteins, as a key mechanism that may contribute to age-related declines in the capacity of myoblasts to undergo differentiation.

INSTRUMENT(S): Synapt MS

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Skeletal Muscle Cell, Skeletal Muscle Tissue Of Trunk

SUBMITTER: Jatin Burniston  

LAB HEAD: Jatin Burniston

PROVIDER: PXD029515 | Pride | 2023-06-27

REPOSITORIES: Pride