Neurofilament protein is phosphorylated in the squid giant axon.
Year: 1978
Type: article
Abstract: We have observed the phosphorylation of neurofilament protein from squid axoplasm. Phosphorylation is demonstrated by 32P labeling of protein during incubation of axoplasm with [gamma-32P]ATP. When the labeled proteins are separated by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), two bands, at 2.0 x 10(5) daltons and greater than 4 x 10(5) daltons, contain the bulk of the 32P. The 2.0 x 10(5)-dalton phosphorylated polypeptide comigrates on SDS-PAGE with one of the subunits of squid neurofilament protein. Both major phosphorylated polypeptides co-fractionate with neurofilaments in discontinuous sucrose gradient centrifugation and on gel filtration chromatography on Sepharose 4B. The protein-phosphate bond behaves like a phospho-ester, and labeled phospho-serine is identified in an acid hydrolysate of the protein. The generality of this phenomenon in various species and its possible physiological significance are discussed.
Source: The Journal of Cell Biology
DOI: 10.1083/jcb.78.2.r23
Authors: H C Pant, G Shecket, H Gainer, R J Lasek
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2070488877