With age comes experience, but also deterioration. To combat aging, body tissues are renewed and microbial cultures rejuvenated. Maintaining one cell young by asymmetric cell division forms the basis for these processes. However, this ability declines with aging, causing an accelerated deterioration. A fundamental understanding of asymmetric cell division, particularly in the context of aging, is minimal. A diffusion barrier between dividing cells is essential for maintaining the asymmetry in the segregation of aging factors and potentially useful cellular content (like memory traces)1. We hypothesize that aging or stress enables yeast to modulate this barrier to share cellular content with off-spring. Sharing harmful aging factors provides the mother cell with a lifespan extension, but at the expense of daughters? fitness. Barrier regulation could also provoke inheritance of useful cellular traces from the mother. Whether this barrier indeed is regulated during aging and/or in response to physiological conditions, will be investigated in this project. Therefore, a method will be developed to quantify the barrier strength. The strength will be quantified during cellular aging and in the context of environmental stress and aging-related perturbations. The specific perturbations will provide molecular insight into regulation of aging-induced decline of the barrier in yeast.