DEVELOPMENTAL PATTERNS OF GENE-EXPRESSION OF SECRETED PROTEINS IN BRAIN AND CHOROID-PLEXUS

Abstract

The proteins secreted by the choroid plexus throughout rat brain development were analyzed by two-dimensional polyacrylamide gel electrophoresis following biosynthetic labeling of choroid plexus pieces with [14C]leucine in vitro. Approximately 20 major protein species were resolved which, with the exception of transferrin, transthyretin, and alpha 2-macroglobulin, appear to be unrelated to proteins found in high concentrations in plasma. Several patterns of developmental regulation were observed. At least two of the proteins were synthesized and secreted at high levels only by fetal choroid plexus, whereas the secretion of several other proteins including transferrin and proteins comigrating..