Role of INK4a locus in normal eye development and cataract genesis

Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Molecular Therapy Research Center, Sungkyunkwan University School of Medicine, 300 Chonchon-Dong, Changan-Gu, Suwon 440-746, Republic of Korea.
Mechanisms of Ageing and Development (Impact Factor: 3.4). 08/2006; 127(7):633-8. DOI: 10.1016/j.mad.2006.02.010
Source: PubMed


The murine INK4a locus encodes the critical tumor suppressor proteins, p16(INK4a) and p19(ARF). Mice lacking both p16(INK4a) and p19(ARF) (INK4a-/-) in their FVB/NJ genetic backgrounds developed cataracts and microophthalmia. Histopathologically, INK4a-/- mice showed defects in the developmental regression of the hyaloid vascular system (HVS), retinal dysplasia, and cataracts with numerous vacuolations, closely resembling human persistent hyperplastic primary vitreous (PHPV). Ocular defects, such as retinal fold and abnormal migration of lens fiber cells, were observed as early as embryonic day (E) 15.5, thereby resulting in the abnormal differentiation of the lens. We also found that ectopic expression of p16(INK4a) resulted in the induction of gammaF-crystallin, suggesting an important role of INK4a locus during mouse eye development, and also providing insights into the potential genetic basis of human cataract genesis.

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Available from: Cheolho Cheong, Dec 18, 2013
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    • "Haematoxylin and eosin (H&E) staining and immunohistochemistry Kidneys were fixed in 10% formalin (Sigma, St. Louis, MO, USA), embedded in paraffin and sectioned at 4-lm intervals. For histological examination, the sections were stained with H&E as described previously (Cheong et al. 2006). To perform the immunohistochemical study, the paraffin sections were incubated with 0.3% H 2 O 2 for 30 min to eliminate endogenous peroxidases, followed by several PBS rinses. "
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