Abstract
Purpose::
Crystallins are the predominant lens proteins. They are now known to be expressed in non-lens tissues. There are three major families of crystallins α, ß and γ. The α crystallins belong to the small heat shock protein family of chaperones. The ß and γ crystallins are structurally related and comprise the ß/γ-crystallin super family. The non lens functions of ß and γ crystallins are not yet understood. We have recently reported that ß and γ crystallins may play a role in vascular remodeling in the mammalian eye. Here we correlate the spatial and temporal expression patterns of ß and γ crystallin during development of the mouse retina and retinal vasculature.
Methods::
Embryonic mouse heads (embryonic days: E12, E16 and E18) and mouse eyes (post natal days: P2, P9 and P12) were obtained from C57Bl6 mice and embeded in OCT. Ten micron sections were immuno-stained for ß and γ crystallins. Isolectin b4 was used to label blood vessels.
Results::
Histological sections of eyes from mice at ages E12, E16, E18, P2, P9 and P12 (3 eyes per time point and 15 sections per eye) showed first measurable retinal expression of ß and γ crystallin on embryonic day 18. On day E18 ß/γ crystallins were detected in both the retina and the hyaloid vasculature. Retinal expression of ß/γ crystallins persisted through the later time points evaluated. ß and γ crystallins were detected in the hyaloid vasculature at E12 and E16, prior their first appearance in the retina.
Conclusions::
To our knowledge this is the first report describing ß and γ crystallin expression during retinal development. ß/γ crystallin expression in the retina is observed as early as embryonic day 18. ß and γ crystallin expression appears to be temporally and spatially associated with retinal vascular development in the mouse.
Keywords: crystallins • development • retina