Related Experiment Video
Updated: Jun 24, 2026

Preparation and Immunofluorescence Staining of Bundles and Single Fiber Cells from the Cortex and Nucleus of the Eye Lens
Published on: June 9, 2023
Interactions between small heat shock protein alpha-crystallin and galectin-related interfiber protein (GRIFIN) in
Kelly A Barton1, Cheng-Da Hsu, J Mark Petrash
1Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Abstract:
As a member of the small heat shock protein superfamily, alpha-crystallin has a chaperone-like ability to recognize and bind denatured or unfolded proteins and prevent their aggregation. Recent studies suggest that alpha-crystallin may also interact with a variety of proteins under native conditions in vitro. To identify potential binding partners for alpha-crystallin in the intact ocular lens, we conducted cross-linking studies in transgenic mouse lenses designed for overexpression of His-tagged human alphaA-crystallin. Interacting proteins were copurified with the epitope-tagged crystallin complexes and were identified by tandem mass spectrometry. This approach identified GRIFIN (galectin-related interfiber protein) as a novel binding partner. Consistent with results from cross-linking, GRIFIN subunits copurified with alpha-crystallin complexes during size exclusion chromatography of nontransgenic mouse lens extracts prepared without chemical cross-linking. Equilibrium binding to GRIFIN was studied using native alpha-crystallin isolated from calf lenses as well as oligomeric complexes reconstituted from recombinant alphaA- and alphaB-crystallin subunits. Calf lens alpha-crystallin binds GRIFIN with relatively high affinity (K(d) = 6.5 +/- 0.8 microM) at a stoichiometry of 0.25 +/- 0.01 GRIFIN monomer/alpha-crystallin subunit. The binding interaction between alpha-crystallin and GRIFIN is enhanced up to 5-fold in the presence of 3 mM ATP. These binding data support the hypothesis that GRIFIN is a novel binding partner of alpha-crystallin in the lens.
Related Concept Videos
Fibril-associated Collagen
For example, the type II collagen fibrils in cartilage have covalently bound type IX fibril-associated collagens at regular intervals. Other types of fibril-associated collagens are...
Glaucoma: Overview
Cytoskeletal Accessory Proteins
Activation and Inactivation of G Proteins
Intracellular Signaling Affects Focal Adhesions
Some...
Golgi Matrix Proteins
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
