In biology, a<unk>  is a water-soluble structural protein found in the lens of the eye, accounting for the transparency of the structure. It has also been identified in other places such as the heart

and aggressive breast cancer tumors 
.
Since it has been shown that lens injury may promote nerve regeneration,<unk>  has been an area of neural research. So far,  it has been demonstrated that<unk>  ß b2 (crybb2) may be a neurite promoting factor
.
Crystallin
Globulin
Glycoprotein
Gamma globulin
Beta globulins
Keratan sulfate
Carrier protein
Fibrous protein