The alpha-crystallins comprise a large fraction of the soluble protein in the vertebrate lens where they were, for many years, believed to function solely as structural proteins. This small family of crystallins is encoded by only two genes, the alpha-A- and alpha-B-crystallin genes and is collectively referred to as alpha-crystallin. They are related to the small heat shock proteins, and in vitro, they exhibit molecular chaperon activity; autokinase activity; and single-stranded, DNA-binding activity; and they interact with and affect the state of several cytoskeletal components. Alpha-crystallin, especially alpha-B-crystallin, has been shown to be a normal constituent of many nonlenticular tissues and has been detected in cytoplasmic inclusion bodies found in several human pathological conditions. To understand the major roles of alpha-crystallin in vivo, we are functionally deleting alpha-crystallin proteins by disrupting or """"""""knocking out"""""""" their genes in mice. We are attempting to elucidate the in vivo functions of alpha-A- and alpha-B-crystallin in (1) lens development and morphogenesis; (2) maintaining a stable, transparent lens throughout the life of an organism (i.e., preventing cataract); (3) the nonlenticular tissues where they are normally present; and (4) nonlenticular pathological conditions. We have generated mice lacking alpha-A-crystallin and mice lacking alpha-B-crystallin. We are presently crossing them to generate mice that are deficient in both alpha-A- and alpha-B-crystallin. Our research has demonstrated that neither alpha-A-crystallin nor alpha-B-crystallin is essential for survival of the laboratory mouse. Because alpha-B-crystallin is highly expressed during embryogenesis in the developing heart and other structures and is a normal constituent of adult heart, skeletal muscle, and several other organs, it was thought to be an essential protein. Analysis of alpha-A-/- mice reveals that lens development occurs relatively normally, and although the wet weight of alpha-A-/- lenses are approximately 35 percent less than that of controls, the gross architecture of the lens is normal, exhibiting an anterior epithelial layer and elongated fiber cells. Dense proteinaceous cytoplasmic inclusion bodies (1 to 3 microns in diameter) form in the fiber cells of these lenses as early as 2 to 4 weeks of age. Alpha-B-crystallin, and modified forms of this protein, has been identified as the major constituent of purified cytoplasmic inclusion bodies. Lens translucence becomes apparent later at 8 to 10 weeks of age.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Intramural Research (Z01)
Project #
1Z01EY000286-04
Application #
2574521
Study Section
Special Emphasis Panel (LMDB)
Project Start
Project End
Budget Start
Budget End
Support Year
4
Fiscal Year
1996
Total Cost
Indirect Cost
Name
U.S. National Eye Institute
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Fujimoto, C; Klinman, D M; Shi, G et al. (2009) A suppressive oligodeoxynucleotide inhibits ocular inflammation. Clin Exp Immunol 156:528-34
Cox, Catherine A; Shi, Guangpu; Yin, Hongen et al. (2008) Both Th1 and Th17 are immunopathogenic but differ in other key biological activities. J Immunol 180:7414-22
Rao, Narsing A; Saraswathy, Sindhu; Wu, Guey Shuang et al. (2008) Elevated retina-specific expression of the small heat shock protein, alphaA-crystallin, is associated with photoreceptor protection in experimental uveitis. Invest Ophthalmol Vis Sci 49:1161-71
Dimberg, Anna; Rylova, Svetlana; Dieterich, Lothar C et al. (2008) alphaB-crystallin promotes tumor angiogenesis by increasing vascular survival during tube morphogenesis. Blood 111:2015-23
Whiston, Emily A; Sugi, Norito; Kamradt, Merideth C et al. (2008) alphaB-crystallin protects retinal tissue during Staphylococcus aureus-induced endophthalmitis. Infect Immun 76:1781-90
Yaung, Jennifer; Kannan, Ram; Wawrousek, Eric F et al. (2008) Exacerbation of retinal degeneration in the absence of alpha crystallins in an in vivo model of chemically induced hypoxia. Exp Eye Res 86:355-65
Wolf, Louise; Yang, Ying; Wawrousek, Eric et al. (2008) Transcriptional regulation of mouse alpha A-crystallin gene in a 148kb Cryaa BAC and its derivates. BMC Dev Biol 8:88
Kreslova, Jana; Machon, Ondrej; Ruzickova, Jana et al. (2007) Abnormal lens morphogenesis and ectopic lens formation in the absence of beta-catenin function. Genesis 45:157-68
Ousman, Shalina S; Tomooka, Beren H; van Noort, Johannes M et al. (2007) Protective and therapeutic role for alphaB-crystallin in autoimmune demyelination. Nature 448:474-9
Verbeek, Richard; van der Mark, Koen; Wawrousek, Eric F et al. (2007) Tolerization of an established alphaB-crystallin-reactive T-cell response by intravenous antigen. Immunology 121:416-26

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