Figure 7.

Patterning of the PN during nucleogenesis. (A) During nucleogenesis, PN neurons populate the target region in an inside-out (dorsoventral) fashion with early born neurons building the inner core of the PN and late born neurons contributing to the outer shell of the PN. (B) The rostrocaudal order of PN neuron progenitors at the lower rhombic lip is maintained by postmitotic PN neurons during tangential migration and nucleogenesis. r6 derived neurons position themselves in the most rostral part of the PN whereas pr8 derived neurons settle in the most caudal part of the PN. PN: pontine nuclei, r: rhombomere, pr: pseudo-rhombomere.