EXPRESSION OF RECEPTOR PROTEIN-TYROSINE PHOSPHATASE-SIGMA (RPTP-SIGMA) IN THE NERVOUS-SYSTEM OF THE DEVELOPING AND ADULT-RAT

The expression of receptor protein tyrosine phosphatase-sigma (RPTP-si gma) mRNA during rat development was examined by Northern blot and in situ hybridization analyses, Northern blot analysis revealed that the two transcripts (5.7 kb and 6.9 kb) had different spatial and temporal patterns of expression, The 6.9-kb transcript was more abundant durin g embryonic development, whereas the 5.7-kb transcript was more abunda nt during postnatal development and in the adult, In situ hybridizatio n revealed that RPTP-sigma mRNA was widely expressed throughout the ce ntral and peripheral nervous system during embryonic development, Very high levels were seen in the ventricular zone, subventricular zone, c ortex, dorsal root ganglia, cranial nerve ganglia, olfactory epitheliu m, and retina, During postnatal development the level of expression de creased in most brain regions, However, high levels continued to be se en in the hippocampus, Emulsion autoradiography revealed that the majo rity of RPTP-sigma mRNA is expressed in neurons, Northern analysis sho wed that cultured glial cells expressed the 6.9-kb transcript, but not the 5.7-kb, RPTP-sigma mRNA expression profiles were clearly distinct from those of leukocyte antigen-related protein (LAR), a closely rela ted RPTP, The spatiotemporal pattern of RPTP-sigma mRNA expression ind icates that RPTP-sigma may play a role in the development of the nervo us system. (C) 1995 Wiley-Liss, Inc.