Musashi-1 (Msi-1) and Partner of Inscuteable (mPins) Are Key Proteins of Mouse Ocular Development and Play Major Roles in Adult Mouse Retinal Structure and Functions

Abstract

Purpose: : : To evaluate the role of Msi-1 and mPins in the seld renewal and asymmetrical cell division of ocular ans especially of retinal stem cells and progenitor cells and to demonstrate the expression of Msi-1 and mPins in adult mouse retinal cells.

Methods: : : We used semi-quantitative RT-PCR, isotopic and non isotopic in situ hybridization on developing mouse and adult mouse tissue sections, western blot analyses and immunohistochemistry with specific anti Msi-1, anti mPins, anti Numb antibodies.

Results: : : We have determined Msi-1 and mPins mRNAs and proteins distributions both in developing and adult mouse eyes. Msi-1 appears to be a marker of stem cells/progenitor cells in most ocular compartments, including the cornea, the limbus, the equatorial germinative lens cells zone and the ciliary marginal zone. We have determined unambiguously the expression of Msi-1 ans mPins in the adult mouse lens and retina. While mPins gene expression is weak during prenatal mouse lens development, it becomes significantly detectable after birth and is readily detected in the adult lens. We also demonstrated the colocalization of mPins and Numb in developing retinoblasts both at E17.5 and P2.

Keywords: gene/expression • development • visual development