Developmental study of proteolipids in bovine brain: a novel proteolipid and DM-20 appear before proteolipid protein (PLP) during myelination.
In a developmental study, we have shown that DM-20 is present before proteolipid protein (PLP) in the fetal bovine cerebral hemispheres. When the white matter appears (27-30 weeks of gestation), the amount of DM-20 drastically increases. DM-20 remains the major proteolipid until birth. PLP is detected only 2-4 weeks after the appearance of white matter, that is, more than 4 weeks after the appearance of DM-20. The early appearance of DM-20 at the beginning of myelination raises the question of its particular function. In the adult bovine cerebral hemispheres, PLP is the major proteolipid but DM-20 remains quantitatively important because the PLP/DM-20 ratio ranges from 1.5 to 1.7. In the same developmental study we have, in the fetal cerebral hemispheres, isolated and characterized a novel proteolipid (apparent Mr 20,000), which appears even before DM-20 and is not detected in the adult brain. It is structurally related to PLP and DM-20 because the first 31 N-terminal amino acid residues are the same. However, in immunoblot, it did not react either with the antitridecapeptide 117-129 antiserum of PLP or with the anti-C-terminal hexapeptide antiserum of PLP.
Laboratoire de Chimie Organique des Substances Naturelles, URA CNRS 31, Strasbourg, France.
P
P
Schindler
B
B
Luu
O
O
Sorokine
E
E
Trifilieff
A
A
Van Dorsselaer
D000818:Animals; D001921:Brain / Q000196:embryology / Q000378:metabolism*; D002417:Cattle; D005333:Fetus / Q000378:metabolism; D009185:Myelin Proteins / Q000378:metabolism*; D018991:Myelin Proteolipid Protein; D009186:Myelin Sheath / Q000502:physiology*; D011510:Proteolipids / Q000737:chemistry / Q000378:metabolism*; D013997:Time Factors
D009185:Myelin Proteins; D018991:Myelin Proteolipid Protein; D011510:Proteolipids