Aging Yeast Cells Undergo a Sharp Entry into Senescence Unrelated to the Loss of Mitochondrial Membrane Potential

Steffen Fehrmann (1) , Camille Paoletti (1) , Youlian Goulev (1) , Andrei Ungureanu (2) , Hugo Aguilaniu (3) , Gilles Charvin (1)

1 IGBMC - Institut de Génétique et de Biologie Moléculaire et Cellulaire
2 Laboratoire Joliot Curie
3 LBMC - Laboratoire de Biologie Moléculaire de la Cellule

In budding yeast, a mother cell can produce a finite number of daughter cells before it stops dividing and dies. Such entry into senescence is thought to result from a progressive decline in physiological function, including a loss of mitochondrial membrane potential (ΔΨ). Here, we developed a microfluidic device to monitor the dynamics of cell division and ΔΨ in real time at single-cell resolution. We show that cells do not enter senescence gradually but rather undergo an abrupt transition to a slowly dividing state. Moreover, we demonstrate that the decline in ΔΨ, which is observed only in a fraction of cells, is not responsible for entry into senescence. Rather, the loss of ΔΨ is an age-independent and heritable process that leads to clonal senescence and is therefore incompatible with daughter cell rejuvenation. These results emphasize the importance of quantitative single-cell measurements to decipher the causes of cellular aging.

Domains: Life Sciences [q-bio]; Biochemistry, Molecular Biology; Molecular biology

Steffen Fehrmann, Camille Paoletti, Youlian Goulev, Andrei Ungureanu, Hugo Aguilaniu, et al.. Aging Yeast Cells Undergo a Sharp Entry into Senescence Unrelated to the Loss of Mitochondrial Membrane Potential. Cell Reports, 2013, 5 (6), pp.1589-1599. ⟨ensl-01074680⟩