Purchase this article with an account.
Chelsey McKenna, Ravi Munjaal, Peter Y. Lwigale; Sema3a/npn1 Signaling Is Required For Proper Innervation Of The Mouse Cornea During Development. Invest. Ophthalmol. Vis. Sci. 2011;52(14):2090.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To identify the expression patterns and Semaphorin3A (Sema3A) and Neuropilin-1 (Npn1) and determine their role during mouse cornea innervation.
The expression of Sema3A and Npn1 was determined at various stages of eye development by section in situ hybridization on wild type mouse embryos. Whole-mount and sections of corneas from wild type and Npn1 mutant mice that are deficient in Sema3A/Npn1 signaling were examined for corneal innervation by immunostaining with a neuron specific beta III tubulin antibody.
The trigeminal ganglion expresses Npn1 by embryonic day (E10.5) and it is maintained throughout the period of corneal innervation. Similarly, Sema3A is expressed in the lens placode as early as E10.5 and becomes confined to the lens epithelium during eye development. In addition, Sema3A is expressed in the periocular mesenchyme and ectoderm surrounding the eye at E11.5. Between E12.5-E16.5, Sema3A is minimally expressed in the mouse presumptive corneal stroma. Npn1 mutant mice display precocious innervation of the cornea by E12.5, which is absent in wild type. All quadrants of the Npn1 mutant corneas are innervated by E13.5 compared with control where innervation of the dorsal temporal quadrant is observed later at E14.5. Unlike control where axons project into the midstromal cornea then towards the surface epithelium, innervation of Npn1 mutant corneas appears to be misguided into the upper regions of the periocular mesenchyme before entry into the cornea. Furthermore, axons that project into the Npn1 mutant corneas precociously innervate the epithelium by E15.5 and aberrantly innervate the posterior regions of the stroma. Interestingly, the swirl pattern observed in adult corneal epithelial innervation does not appear to be affected in Npn1 mutant corneas.
Sema3A/Npn1 signaling regulates mouse corneal innervation and guides axonal projections towards the corneal epithelium during development.
This PDF is available to Subscribers Only