Up to 30 percent of the vertebrate eye lens is composed of the small heat shock protein alpha-crystallin. This protein acts as a molecular chaperone, preventing the stress-induced aggregation of denatured proteins that can lead to cataracts. The central premise of this proposal is that the chaperone activity of alpha-crystallin is dependent on temperature, and that its amino acid composition has evolved to maintain chaperone function in different thermal environments. Alpha-crystallin consists of two subunits, alphaA and alphaB, that arose from a gene duplication event and have different chaperone properties. This proposal seeks to determine the relationship between the structure and chaperone function of alphaA- and alphaB-crystallin from the zebrafish. This study will assay, for the first time, chaperone function of alpha-crystallin from an ectothermic vertebrate. This information will be directly compared to the structural and chaperone properties of human alphaAand alphaB-crystallin to determine whether chaperone function adapts to the physiological temperatures of different species. These data will provide a reference point for a large body of researchers interested in small heat shock protein function and cataracts, and will build the basic knowledge necessary for further studies on the thermal adaptation of alpha-crystallin.
The aims proposed will be accomplished using an interdisciplinary approach combining molecular biology, protein biochemistry, ecology and evolution. The senior investigator's diverse background in fish evolution, fish ecology, and molecular techniques makes him uniquely qualified to carry out this interdisciplinary research project.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Academic Research Enhancement Awards (AREA) (R15)
Project #
1R15EY013535-01
Application #
6358687
Study Section
Visual Sciences A Study Section (VISA)
Program Officer
Liberman, Ellen S
Project Start
2001-08-01
Project End
2004-07-31
Budget Start
2001-08-01
Budget End
2004-07-31
Support Year
1
Fiscal Year
2001
Total Cost
$91,800
Indirect Cost
Name
Ashland University
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
City
Ashland
State
OH
Country
United States
Zip Code
44805
Posner, Mason; Murray, Kelly L; McDonald, Matthew S et al. (2017) The zebrafish as a model system for analyzing mammalian and native ?-crystallin promoter function. PeerJ 5:e4093
Posner, Mason; Skiba, Jackie; Brown, Mary et al. (2013) Loss of the small heat shock protein ?A-crystallin does not lead to detectable defects in early zebrafish lens development. Exp Eye Res 116:227-33
Wages, Phillip; Horwitz, Joseph; Ding, Linlin et al. (2013) Changes in zebrafish (Danio rerio) lens crystallin content during development. Mol Vis 19:408-17
Posner, Mason; Kiss, Andor J; Skiba, Jackie et al. (2012) Functional validation of hydrophobic adaptation to physiological temperature in the small heat shock protein ?A-crystallin. PLoS One 7:e34438
Posner, Mason; Hawke, Molly; Lacava, Carrie et al. (2008) A proteome map of the zebrafish (Danio rerio) lens reveals similarities between zebrafish and mammalian crystallin expression. Mol Vis 14:806-14
Smith, Amber A; Wyatt, Keith; Vacha, Jennifer et al. (2006) Gene duplication and separation of functions in alphaB-crystallin from zebrafish (Danio rerio). FEBS J 273:481-90
Dahlman, Jason M; Margot, Kelli L; Ding, Linlin et al. (2005) Zebrafish alpha-crystallins: protein structure and chaperone-like activity compared to their mammalian orthologs. Mol Vis 11:88-96
Runkle, Stephanie; Hill, Julie; Kantorow, Marc et al. (2002) Sequence and spatial expression of zebrafish (Danio rerio) alphaA-crystallin. Mol Vis 8:45-50