Involvement of protein kinase C in the regulation of assembly-disassembly of neurofilaments in vitro

Abstract Protein kinase C phosphorylated the major mammalian neurofilament protein (NF-L) with ∼3 mol phosphate per mol protein. The phosphorylated NF-L no longer formed the filaments. Sequential analysis of the tryptic phosphopeptides, together with the known primary sequence, revealed that Ser-12, Ser-27, Ser-33 and Ser-51 were phosphorylated by protein kinase C. These findings contribute toward elucidation of mechanisms regulating the functions of neurofilaments.