FIGURE 2.

A complete view of aNSC quiescence. (A) Representation of the states matrix for the DG showing the four main outlets, neurogenesis, astrogenesis, senescence, and apoptosis. Their relative weight depends on the age and condition (e.g., stress levels, disease, etc.) of the animal. (B) Representation of the states matrix for the SEZ, in which oligodendrogenesis is also an important outlet. S, senescence; A, astrogenesis; O, oligodendrogenesis; N, neurogenesis. (C) cell can reversibly transition through the matrix space and several paths are possible for the same outcome (in this case, neurogenesis). (D) One of our hypotheses is that systemic stimuli, such as diet of exercise, will shift the cells in the matrix to a slightly different state. This could then affect how they respond to additional stimuli. (E) We also notice that proliferation is inversely correlated with stemness, which suggests that quiescence and stemness could be functionally linked. aNSCs lose self-renewing potential as they continue proliferating. S.R.: symmetric self-renewal, A.R.: asymmetric self-renewal, S.D.: symmetric differentiation.