Slow anterograde axonal transport of calpain I and II.

Following intravitreal injections of (35)S-amino acids to label axonally transported proteins, calpain I and II from the superior colliculi and the lateral geniculate bodies were isolated via hydrophobic interaction chromatography, anion exchange HPLC and sodium-dodecyl sulphate electrophoresis. Among the slowly transported proteins radioactive label was associated with molecular weight components corresponding to both the light (approx. 30 kDa) and the heavy (approx. 80 kDa) subunits of calpain I as well as with the corresponding subunits of calpain II. Among the fast transported material no radioactive protein bands were detected in these fractions.