Alpha crystallins are composed of two gene products , alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein(sHSP also known as the HSP20). They act as molecular chaperones and hold them in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits, the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional functions of alpha-crystallins are an autokinase activity and participation in the intracellular architecture. The expression of alpha-A is preferentially restricted to the lens cell. Alternative Names: Alpha-crystallin A chain protein, Crystallin Alpha 1 protein, Acry-1 protein, CRYAA protein, HSPB 4 protein, Crystallin alpha A protein, , HspB4 protein, CRYA 1 protein, Heat shock protein beta 4 protein, Zonular Central Nuclear Cataract protein, Alpha crystallin A chain protein, CRYA1 protein, Heat shock protein beta-4 protein