This analysis reveals that bRG-apical-P corresponds mostly to lower daughters (79.3%), whereas bRG-basal-P corresponds to upper daughters (94.7%). Interestingly, Tc of sister daughters that both divide again are correlated and show a certain degree IWR-1 nmr of synchronization with that of the mother cell ( Figures 5F and 5G). We failed to detect any effect of the relative upper or lower position of the two daughter cells on their neuron versus precursor fate (data not shown). We have extracted quantitative information regarding the precursor fate by a clonal analysis of a database including 695 cells and 306 divisions at E65 and E78 (Figure S4A). This

established distinctive stage-specific proliferative, self-renewing, and neurogenic characteristics for the five precursor types. The five precursor types exhibit marked statistical differences in their order of apparition in the lineage trees. At E78, bRG-both-P cells and bRG-basal-P cells are predominant in the early ranks of lineage trees, bRG-apical-P cells at intermediate ranks, whereas tbRG and IP cells are observed at the later ranks of

division ( Figure 6A). A similar but less pronounced trend is observed at E65 ( Figure S4B). Quantitative analysis of the progeny of each precursor type showed important qualitative and quantitative differences. All five precursor types are able to generate neurons and to self-renew, i.e., to Vorinostat mouse generate at least one daughter of the same type as the mother cell. At both E65 and E78, we observed a self-renewal gradient, which is maximum in bRG-both-P, bRG-apical-P, and tbRG cells, intermediate in IP cells, and low in bRG-basal-P cells ( Figure 6B). This suggests that the presence of the apical not process is an important factor in conferring self-renewal properties to bRG cells. The five precursor types exhibit different trends in their neurogenic capacity. At E78, bRG-both-P cells show the highest and IP cells the lowest proportions of neuronal progeny ( Figure 6C).

Variations in the neurogenic capacity of the different precursor types influence the size of their progeny. For instance, bRG-both-P and IP cells have comparable progeny ( Figure 6D; Figure S4C), despite the fact that they are respectively at the top and bottom ranks of the lineage trees. The similarity in progeny of these two precursor types is due to the fact that IP cells have considerably lower neurogenic potential compared to bRG-both-P cells ( Figure 6C). The quantitative differences in the neurogenic potential and rates of self-renewal coupled with lineage rank suggest that different precursor types have distinct relationships. In order to investigate this, we developed a formal graphic description of the full repertoire of precursor behavior. In these state transition diagrams (Harel, 1987), nodes (or states) represent precursor types and directed edges the transitions between precursors (i.e., precursor progeny).