Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2011-3-28
pubmed:abstractText
Mental retardation in Down syndrome (DS) appears to be related to severe neurogenesis impairment during critical phases of brain development. Recent lines of evidence in the cerebellum of a mouse model for DS (the Ts65Dn mouse) have shown a defective responsiveness to Sonic Hedgehog (Shh), a potent mitogen that controls cell division during brain development, suggesting involvement of the Shh pathway in the neurogenesis defects of DS. Based on these premises, we sought to identify the molecular mechanisms underlying derangement of the Shh pathway in neural precursor cells (NPCs) from Ts65Dn mice. By using an in vitro model of NPCs obtained from the subventricular zone and hippocampus, we found that trisomic NPCs had an increased expression of the Shh receptor Patched1 (Ptch1), a membrane protein that suppresses the action of a second receptor, Smoothened (Smo), thereby maintaining the pathway in a repressed state. Partial silencing of Ptch1 expression in trisomic NPCs restored cell proliferation, indicating that proliferation impairment was due to Ptch1 overexpression. The overexpression of Ptch1 in trisomic NPCs resulted from increased levels of AICD [a transcription-promoting fragment of amyloid precursor protein (APP)] and increased AICD binding to the Ptch1 promoter. Our data provide novel evidence that Ptch1 overexpression underlies derangement of the Shh pathway in trisomic NPCs with consequent proliferation impairment. The demonstration that Ptch1 overexpression in trisomic NPCs is due to an APP fragment provides a link between this trisomic gene and the defective neuronal production that characterizes the DS brain.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Amyloid beta-Protein Precursor, http://linkedlifedata.com/resource/pubmed/chemical/Bmi1 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Cyclohexylamines, http://linkedlifedata.com/resource/pubmed/chemical/Forkhead Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/Foxm1 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Gli protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Gli2 protein, http://linkedlifedata.com/resource/pubmed/chemical/Gli3 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Hedgehog Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Kruppel-Like Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cell Surface, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, G-Protein-Coupled, http://linkedlifedata.com/resource/pubmed/chemical/Repressor Proteins, http://linkedlifedata.com/resource/pubmed/chemical/SAG compound, http://linkedlifedata.com/resource/pubmed/chemical/Shh protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Smo protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Thiophenes, http://linkedlifedata.com/resource/pubmed/chemical/Veratrum Alkaloids, http://linkedlifedata.com/resource/pubmed/chemical/cyclopamine, http://linkedlifedata.com/resource/pubmed/chemical/patched receptors
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1460-2083
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1560-73
pubmed:meshHeading
pubmed-meshheading:21266456-Acetylation, pubmed-meshheading:21266456-Amyloid beta-Protein Precursor, pubmed-meshheading:21266456-Animals, pubmed-meshheading:21266456-Cell Cycle, pubmed-meshheading:21266456-Cell Proliferation, pubmed-meshheading:21266456-Cyclohexylamines, pubmed-meshheading:21266456-DNA Methylation, pubmed-meshheading:21266456-Down Syndrome, pubmed-meshheading:21266456-Female, pubmed-meshheading:21266456-Forkhead Transcription Factors, pubmed-meshheading:21266456-Hedgehog Proteins, pubmed-meshheading:21266456-Hippocampus, pubmed-meshheading:21266456-Humans, pubmed-meshheading:21266456-Kruppel-Like Transcription Factors, pubmed-meshheading:21266456-Lateral Ventricles, pubmed-meshheading:21266456-Male, pubmed-meshheading:21266456-Mice, pubmed-meshheading:21266456-Mice, Inbred C57BL, pubmed-meshheading:21266456-Nerve Tissue Proteins, pubmed-meshheading:21266456-Neural Stem Cells, pubmed-meshheading:21266456-Neurons, pubmed-meshheading:21266456-Nuclear Proteins, pubmed-meshheading:21266456-Promoter Regions, Genetic, pubmed-meshheading:21266456-Protein Structure, Tertiary, pubmed-meshheading:21266456-Proto-Oncogene Proteins, pubmed-meshheading:21266456-RNA Interference, pubmed-meshheading:21266456-Receptors, Cell Surface, pubmed-meshheading:21266456-Receptors, G-Protein-Coupled, pubmed-meshheading:21266456-Repressor Proteins, pubmed-meshheading:21266456-Thiophenes, pubmed-meshheading:21266456-Up-Regulation, pubmed-meshheading:21266456-Veratrum Alkaloids
pubmed:year
2011
pubmed:articleTitle
APP-dependent up-regulation of Ptch1 underlies proliferation impairment of neural precursors in Down syndrome.
pubmed:affiliation
Department of Human and General Physiology, University of Bologna, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't