title: The expression of GAP-43 mRNA in developing embryonic striatal tissue grafts.
abstract: We have studied by quantitative in situ hybridization histochemistry the mRNA expression of the growth associated phosphoprotein (GAP-43) in grafts of foetal striatal neurones implanted into the ibotenic acid lesioned adult rat neostriatum. Animals were studied at 7, 15, 30 and 90 days after implantation. Using a 35S-labelled specific oligonucleotide probe we observed the highest levels of GAP-43 mRNA in 15-day-old grafts; levels were significantly reduced at 30 days and in 3-month-old grafts GAP-43 mRNA expression was not significantly different from the very low levels in the normal rat striatum. The data indicate that GAP-43 mRNA is highly expressed in developing but not mature neurones and suggest that embryonic striatal grafts may develop a relatively adult phenotype within the host brain by about 4 weeks; by which time most of the synaptic connections are established.
authors.affiliation: Department of Neurobiology, AFRC Institute of Animal Physiology and Genetics Research, Brabraham, Cambridge, UK.
authors.forename: D J
authors.initials: DJ
authors.lastname: Sirinathsinghji
authors.forename: E
authors.initials: E
authors.lastname: Mayer
authors.forename: R
authors.initials: R
authors.lastname: Stam
authors.forename: J M
authors.initials: JM
authors.lastname: Fernandez
authors.forename: S B
authors.initials: SB
authors.lastname: Dunnett
mesh_terms: D000818:Animals; D016375:Antisense Elements (Genetics); D001345:Autoradiography; D015152:Blotting, Northern; D016380:Brain Tissue Transplantation / Q000502:physiology*; D003342:Corpus Striatum / Q000502:physiology* / Q000637:transplantation*; D005260:Female; D016332:Fetal Tissue Transplantation / Q000502:physiology; D019922:GAP-43 Protein; D015870:Gene Expression; D006133:Growth Substances / Q000235:genetics; D007051:Ibotenic Acid; D017403:In Situ Hybridization; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D011061:Poly A / Q000235:genetics / Q000302:isolation & purification; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013462:Sulfur Radioisotopes; D013997:Time Factors
chemical_list: D016375:Antisense Elements (Genetics); D019922:GAP-43 Protein; D006133:Growth Substances; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D013462:Sulfur Radioisotopes; D011061:Poly A; D007051:Ibotenic Acid; D012313:RNA