Dual transgenic reporter mice as a tool for monitoring expression of glial fibrillary acidic protein.
Glial fibrillary acidic protein (GFAP) is the major intermediate filament protein of astrocytes, and its expression changes dramatically during development and following injury. To facilitate study of the regulation of GFAP expression, we have generated dual transgenic mice expressing both firefly luciferase under the control of a 2.2 kb human GFAP promoter and Renilla luciferase under the control of a 0.5 kb human Glyceraldehyde 3 phosphate dehydrogenase (GAPDH) promoter for normalization of the GFAP signal. The GFAP-fLuc was highly expressed in brain compared to other tissues, and was limited to astrocytes, whereas the GAPDH-RLuc was more widely expressed. Normalization of the GFAP signal to the GAPDH signal reduced the inter-individual variability compared to using the GFAP signal alone. The GFAP/GAPDH ratio correctly reflected the up-regulation of GFAP that occurs following retinal degeneration in FVB/N mice because of the rd mutation. Following kainic acid-induced seizures, changes in the GFAP/GAPDH ratio precede those in total GFAP protein. In knock-in mice expressing the R236H Alexander disease mutant, GFAP promoter activity is only transiently elevated and may not entirely account for the accumulation of GFAP protein that takes place.
Cho
Woosung
W
Waisman Center and Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA. cho@waisman.wisc.edu
Hagemann
Tracy L
TL
Johnson
Delinda A
DA
Johnson
Jeffrey A
JA
Messing
Albee
A
D038261:Alexander Disease / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004827:Epilepsy / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics*; D055879:Gene Knock-In Techniques; D017930:Genes, Reporter / Q000235:genetics*; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics* / Q000378:metabolism; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000235:genetics*; D049409:Luciferases, Firefly / Q000235:genetics; D049410:Luciferases, Renilla / Q000235:genetics; D051379:Mice; D008818:Mice, Neurologic Mutants; D008822:Mice, Transgenic; D008967:Molecular Biology / Q000379:methods*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012162:Retinal Degeneration / Q000235:genetics / Q000378:metabolism; D019076:Transgenes / Q000235:genetics*
D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D008156:Luciferases; D049410:Luciferases, Renilla; D049409:Luciferases, Firefly; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)