Expression of fructose-1,6-bisphosphatase mRNA isoforms in normal and basal forebrain cholinergic lesioned rat brain.
Fructose-1,6-bisphosphatase is one of the key enzymes in the gluconeogenic pathway predominantly occurring in liver, kidney and muscle. In the brain, fructose-1,6-bisphosphatase has been suggested to be an astrocyte-specific enzyme but the functional importance of glyconeogenesis in the brain is still unclear. To further elucidate the cellular source of fructose-1,6-bisphosphatase in the brain, non-radioactive in situ hybridizations were performed using digoxigenin-labeled RNA probes based on the sequence of recently cloned rat liver and muscle fructose-1,6-bisphosphatase cDNAs. In situ hybridization using a riboprobe for the liver isoform revealed a location of the hybridization signal mainly in neurons, while rat muscle fructose-1,6-bisphosphatase mRNA was detected in both neurons and astrocytes in the hippocampal formation and in layer I of the cerebral cortex.RT-PCR using RNA preparations of rat astrocytes, neurons, and adult whole brain demonstrated a localization of liver fructose-1,6-bisphosphatase mRNA isoform in neurons but not in astrocytes. The muscle fructose-1,6-bisphosphatase mRNA isoform could be detected by RT-PCR in total rat brain, astrocytic, and neuronal mRNA preparations. The isoforms of fructose-1,6-bisphosphatase mRNA seemingly demonstrate a distinct cellular expression pattern in rat brain suggesting a role of glyconeogenesis in both neurons and glial cells.
Löffler
T
T
Paul Flechsig Institute for Brain Research, Department of Neurochemistry, Jahnallee 59, D-04109, Leipzig, Germany.
Al-Robaiy
S
S
Bigl
M
M
Eschrich
K
K
Schliebs
R
R
D000818:Animals; D001253:Astrocytes / Q000737:chemistry / Q000201:enzymology; D002799:Cholinergic Fibers / Q000201:enzymology*; D003714:Denervation; D006597:Fructose-Bisphosphatase / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D005943:Gluconeogenesis / Q000502:physiology*; D017403:In Situ Hybridization; D007527:Isoenzymes / Q000235:genetics* / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000201:enzymology; D016548:Prosencephalon / Q000166:cytology / Q000378:metabolism*; D015347:RNA Probes; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar
D005904:Glial Fibrillary Acidic Protein; D007527:Isoenzymes; D015347:RNA Probes; D012333:RNA, Messenger; D006597:Fructose-Bisphosphatase