During brain development, neural stem cells and neural progenitor cells (NPCs) have to proliferate, migrate and differentiate in highly accurate patterns; this is controlled by both genetic programmes and specific factors in the microniches. Bradykinin has recently been implicated in the determination of neural cell fate; however, the underlying mechanisms are not clear. In their study on page 3437, Henning Ulrich and co-workers now seek a better understanding of the role of this factor in neurogenesis. They report here that, in the presence of bradykinin, proliferating NPCs adopt a longer G1 phase, which is characteristic for cells that generate neurons as opposed to those undergoing a proliferative cell division. This is the case both in vivo, as observed in hippocampus from newborn mice, as well as in vitro in rat NPCs. Their subsequent analysis of the signalling pathways that are induced by bradykinin demonstrates that neurogenesis in vitro and in vivo depends on activation of the extracellular-regulated kinase (ERK) pathway; this involves sustained ERK phosphorylation and its nuclear translocation, which modulates the expression of Hes1 and Ngn2. Taken together, this study proposes a previously undescribed role for bradykinin in neuron-generating division, and the underlying mechanisms could have important implications for therapeutic approaches aimed at neuronal repair.
- © 2016. Published by The Company of Biologists Ltd