Small Heat Shock Proteins (sHSP) are critical molecular chaperones that function to maintain protein homeostasis (proteostasis) and prevent the aggregation of other proteins during cellular stress. Any disruption in the process of proteostasis can lead to prevalent diseases ranging from cancer and cataract to cardiovascular and Alzheimer's disease. CryAB (αB-crystallin, HspB5) is one of ten known human sHSP that is abundant in the lens, skeletal, and cardiac muscle. This protein is required for cardiac function and muscle cell integrity. When the cell experiences physiological stress, including heat shock, CryAB moves to the cytoskeleton to act as a chaperone and prevent aggregation of its protein clientele. This research is designed to investigate the molecular role of CryAB in cell proteostasis through the identification of putative protein clientele and chaperone activity analysis. We have identified over twenty CryAB-binding partners through combined yeast two-hybrid (Y2H) and co-purification approaches, including interactions with myofibril proteins. Previously reported disease-associated CryAB missense variants were analyzed in comparison to wild type CryAB through Y2H binding assays. The characterization of the similarities and differences in binding specificities of these variants provide a foundation to better understand the chaperone pathways of CryAB and how these changes in molecular function result in the development of disparate diseases such as cataract, cancer, and various myopathies.
College and Department
Life Sciences; Microbiology and Molecular Biology
BYU ScholarsArchive Citation
Hoopes, Whitney Katherine, "A CryAB Interactome Reveals Clientele Specificity and Dysfunction of Mutants Associated with Human Disease" (2016). All Theses and Dissertations. 6576.
small Heat Shock Proteins (sHSP), HspB5 (αB-crystallin, CryAB), molecular chaperones, proteostasis, R120G, HspB2