title: Activation of GSK-3 and phosphorylation of CRMP2 in transgenic mice expressing APP intracellular domain.
abstract: Amyloid precursor protein (APP), implicated in Alzheimer's disease, is a trans-membrane protein of undetermined function. APP is cleaved by gamma-secretase that releases the APP intracellular domain (AICD) in the cytoplasm. In vitro studies have implicated AICD in cell signaling and transcriptional regulation, but its biologic relevance has been uncertain and its in vivo function has not been examined. To investigate its functional role, we generated AICD transgenic mice, and found that AICD causes significant biologic changes in vivo. AICD transgenic mice show activation of glycogen synthase kinase-3beta (GSK-3beta) and phosphorylation of CRMP2 protein, a GSK-3beta substrate that plays a crucial role in Semaphorin3a-mediated axonal guidance. Our data suggest that AICD is biologically relevant, causes significant alterations in cell signaling, and may play a role in axonal elongation or pathfinding.
authors.affiliation: Department of Pathology and Cell Biology Program, Case Western Reserve University, Cleveland, OH 44106, USA.
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Ryan
authors.forename: Sanjay W
authors.initials: SW
authors.lastname: Pimplikar
mesh_terms: D016564:Amyloid beta-Protein Precursor / Q000235:genetics / Q000502:physiology*; D000818:Animals; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010766:Phosphorylation; D017434:Protein Structure, Tertiary / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D016564:Amyloid beta-Protein Precursor; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C095114:collapsin response mediator protein-2; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; D038362:Glycogen Synthase Kinase 3