MAJOR GLYCOPROTEINS IN CARP CNS MYELIN - HOMOLOGY TO P0 PROTEIN WITH HNK-1 L2 CARBOHYDRATE EPITOPE/

We studied the myelin protein profiles of carp from a phylogenetic poi nt of view. The carp central nerve myelin contained two reactive bands . 28 and 25 kDa, demonstrated with anti-bovine P0 antibody. Their mole cular weights are slightly different from those of two positive bands found in carp peripheral myelin. The N-terminal amino acid sequences o f these four positive bands were identical to one another and showed h igh homology with those of mammalian P0 protein, suggesting that carp central myelin contains the P0-like protein. Lectin binding analysis r evealed that carbohydrate structure of the P0-like proteins in carp ce ntral myelin is similar to those in peripheral myelin of carp and othe r vertebrates. Further, the carp P0-like glycoproteins, like the PO pr oteins of other vertebrates, reacted with antibodies that recognize th e HNK-1/L2 carbohydrate epitope. We conclude that the major structural glycoprotein in central myelin of the carp is homologous to PO protei n in peripheral myelin of other higher classes of vertebrates.