Ependymal Planar Cell Polarity in the SVZ Neurogenic Niche

Abstract

In this study, we mapped stages in the development of planar cell polarity in 3 ages of infant mice (3, 8, and 11 days post-partum). We found an increasing asymmetry, ventral alignment, and transition from disorganized to organized ciliary beating. Next, we explored the effect of healthy-tissue modulation on the normally developing planar cell polarity. Modulation of previously healthy tissue mirrors the effect of sudden-onset diseases like stroke and brain injury. Both environmental and biochemical modulations were produced in-vitro. We found that healthy developing ependymal cells were sensitive to these changes. Removal of fluid flow led to loss of asymmetrical planar polarity, loss of cilia, and more disorganized ciliary beating. Suppression of FOXJ1, an important biochemical transcription factor, in previously healthy immature cells led to loss of cilia and greater misalignment of basal bodies.