Brn3b/Brn3cdouble knockout mice reveal an unsuspected role for Brn3c in retinal ganglion cell axon outgrowth

• DOI: 10.1242/dev.129.2.467
• Publication Date: 2021-04-25T13:23:20Z
• Authors: Steven W. Wang; Xiuqian Mu; William J. Bowers; Dong-Seob Kim; Daniel J. Plas; Michael C. Crair; Howard J. Federoff; Lin Gan; William H. Klein
• Keywords: Knockout mouse

In mice, Brn3 POU domain transcription factors play essential roles in the differentiation and survival of projection neurons within retina, inner ear, dorsal root trigeminal ganglia. During retinal ganglion cell differentiation, Brn3b is expressed first, followed by Brn3a Brn3c. Targeted deletion Brn3b, but not or Brn3c, leads to a loss most cells before birth. However, as few are still present Brn3b–/– Brn3c may partially compensate for Brn3b. To examine role development, we generated Brn3b/Brn3c double knockout mice analyzed their retinas optic chiasms. Retinal axons from were more severely affected than those Brn3b-deficient indicating that was required could Moreover, had functions separate Ipsilateral misrouted projections at chiasm overproduced missing entirely chiasms suggesting controlled ipsilateral axon production. Forced expression explants restored neurite outgrowth, demonstrating promote outgrowth absence Our results reveal complex genetic relationship between regulating outgrowth.