Purchase this article with an account.
A. L. Grabitz, D. A. Scheiblin, M. K. Duncan; Lens Fiber Cell Morphology is Affected by Sip1 Conditional Deletion. Invest. Ophthalmol. Vis. Sci. 2010;51(13):2351.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Sip-1, or Smad interacting protein 1, is a member of the Zeb protein family and is a known binding partner of Smad proteins that co-regulate TGFB induced epithelial-mesenchymal transition (EMT). Sip-1 is critical for the separation of the lens vesicle from the head ectoderm and the later expression of γ-crystallin in lens fibers. This work tests the hypothesis that Sip-1 plays a role in lens fiber cell differentiation and structure.
Mice homozygous for the Sip-1 flox allele were bred with mice carrying the MLR10 Cre gene, which is expressed throughout the lens vesicle. Gene deletion was assessed by immunofluorescent localization of Sip1 and PCR. The structure of lenses lacking Sip1 was assessed by scanning electron microscopy (SEM) and conventional histological methods. Crystallin expression was investigated using gel electrophoresis and protein staining. C57B6 mice were used as the wild type controls.
Conditional deletion of Sip1results in profound defects in the shape and structure of lens fiber cells beginning at approximately the lens vesicle stage of embryonic development. Additionally, conditional deletion of Sip1 results in fiber cells with a very disordered ball and socket structure in comparison to controls. Crystallin expression, however, is not dramatically altered upon the loss of Sip1.
These data indicate that Sip-1 is important for lens fiber cell differentiation and fiber cell structure. However, our data suggest that Sip1 is not essential for crystallin expression in the lens. Future work will investigate the targets of Sip1 in the lens and how these targets regulate lens structure.
This PDF is available to Subscribers Only