Cataract is the most common cause of blindness in the world today. Surgery is generally very effective in restoring sight;however, a common complication is the development of posterior capsule opacification. This is caused by aberrant growth and differentiation of lens cells. One way to prevent this costly complication is to promote normal patterns of lens cell growth and differentiation. In relation to fiber differentiation, evidence indicates that members of the Wnt growth factor family, through activation of the Wnt/planar cell polarity (PCP) signaling pathway, provide a critical component of a FGF- induced signaling cascade that is required for fiber differentiation. This project will test the hypothesis that Wnt/PCP signaling plays a critical role in directing the elongation, migration and alignment of lens fibers. In Part (a), investigations by RT-PCR, in situ hybridisation, immunolocalization and Western blotting, will determine expression patterns of members of the core Wnt/PCP signaling families, prickle, van gogh-like and scribble, during lens development. Part (b) will then manipulate expression of PCP signaling components in lens epithelial explants and in transgenic mice to determine their functional roles in fiber differentiation. Using siRNA, dominant-negative and conditional knockout strategies the functions of the PCP signaling components (identified in a) in promoting the elongation, directed migration and alignment of lens fibers, will be tested. These studies will provide vital new information about mechanisms and molecules that are required to promote the growth, differentiation and maintenance of lens cells and in so doing will address key objectives identified within the 'Lens and Cataract Program'of NEI.

Public Health Relevance

With approximately 20 million people affected, clouding of the lens (cataract) is the most common cause of blindness in the world today. Although surgery can initially be very effective in restoring sight, in the longer term complications are common and often result in the development of a secondary cataract. A central aim in our laboratory is to devise molecular strategies that (i) prevent the aberrant lens cell behaviour that occurs after surgery and (ii) promote normal patterns of lens cell growth and differentiation so that lens clarity is maintained.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY003177-29
Application #
7995948
Study Section
Anterior Eye Disease Study Section (AED)
Program Officer
Araj, Houmam H
Project Start
1991-09-30
Project End
2011-11-30
Budget Start
2010-12-01
Budget End
2011-11-30
Support Year
29
Fiscal Year
2011
Total Cost
$157,453
Indirect Cost
Name
University of Sydney
Department
Type
DUNS #
752389338
City
Sydney
State
Country
Australia
Zip Code
2006
Dawes, L J; Shelley, E J; McAvoy, J W et al. (2018) A role for Hippo/YAP-signaling in FGF-induced lens epithelial cell proliferation and fibre differentiation. Exp Eye Res 169:122-133
Zhao, Guannan; Bailey, Charles G; Feng, Yue et al. (2018) Negative regulation of lens fiber cell differentiation by RTK antagonists Spry and Spred. Exp Eye Res 170:148-159
Shu, Daisy Y; Wojciechowski, Magdalena C; Lovicu, Frank J (2017) Bone Morphogenetic Protein-7 Suppresses TGF?2-Induced Epithelial-Mesenchymal Transition in the Lens: Implications for Cataract Prevention. Invest Ophthalmol Vis Sci 58:781-796
Wojciechowski, Magdalena C; Mahmutovic, Leila; Shu, Daisy Y et al. (2017) ERK1/2 signaling is required for the initiation but not progression of TGF?-induced lens epithelial to mesenchymal transition (EMT). Exp Eye Res 159:98-113
McAvoy, J W; Dawes, L J; Sugiyama, Y et al. (2017) Intrinsic and extrinsic regulatory mechanisms are required to form and maintain a lens of the correct size and shape. Exp Eye Res 156:34-40
Shu, Daisy Y; Lovicu, Frank J (2017) Myofibroblast transdifferentiation: The dark force in ocular wound healing and fibrosis. Prog Retin Eye Res 60:44-65
Lovicu, F J; Shin, E H; McAvoy, J W (2016) Fibrosis in the lens. Sprouty regulation of TGF?-signaling prevents lens EMT leading to cataract. Exp Eye Res 142:92-101
Audette, Dylan S; Anand, Deepti; So, Tammy et al. (2016) Prox1 and fibroblast growth factor receptors form a novel regulatory loop controlling lens fiber differentiation and gene expression. Development 143:318-28
Sugiyama, Yuki; Shelley, Elizabeth J; Yoder, Bradley K et al. (2016) Non-essential role for cilia in coordinating precise alignment of lens fibres. Mech Dev 139:10-7
Das, Shannon J; Lovicu, Frank J; Collinson, Emma J (2016) Nox4 Plays a Role in TGF-?-Dependent Lens Epithelial to Mesenchymal Transition. Invest Ophthalmol Vis Sci 57:3665-73

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