AlphaB-crystallin regulates intermediate filament organization in situ.

AlphaB-crystallin is a small heat shock protein (hsp) and molecular chaperone that can interact with a wide spectrum of cellular components including intermediate filaments (IF). The significance of these interactions is not currently known. We have tested whether increased alphaB-crystallin expression effects changes in the IF systems in situ. Adenoviral-mediated gene transfer was used to overexpress alphaB-crystallin in primary astrocytes. A positive correlation was observed between overexpression of alphaB-crystallin and diffuse, filigree IF. AlphaB-crystallin did not appear to alter the polymerization state of IF proteins. These data show that an increase in alphaB-crystallin expression in the absence of stress can modify the organizational state of IF and that alphaB-crystallin can function as an IF debundling protein.