title: Drosophila fragile X protein, DFXR, regulates neuronal morphology and function in the brain.
abstract: Mental retardation is a pervasive societal problem, 25 times more common than blindness for example. Fragile X syndrome, the most common form of inherited mental retardation, is caused by mutations in the FMR1 gene. Fragile X patients display neurite morphology defects in the brain, suggesting that this may be the basis of their mental retardation. Drosophila contains a single homolog of FMR1, dfxr (also called dfmr1). We analyzed the role of dfxr in neurite development in three distinct neuronal classes. We find that DFXR is required for normal neurite extension, guidance, and branching. dfxr mutants also display strong eclosion failure and circadian rhythm defects. Interestingly, distinct neuronal cell types show different phenotypes, suggesting that dfxr differentially regulates diverse targets in the brain.
authors.affiliation: Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Joannella
authors.initials: J
authors.lastname: Morales
authors.forename: P Robin
authors.initials: PR
authors.lastname: Hiesinger
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Schroeder
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Kume
authors.forename: Patrik
authors.initials: P
authors.lastname: Verstreken
authors.forename: F Rob
authors.initials: FR
authors.lastname: Jackson
authors.forename: David L
authors.initials: DL
authors.lastname: Nelson
authors.forename: Bassem A
authors.initials: BA
authors.lastname: Hassan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000473:pathology / Q000502:physiology*; D002940:Circadian Rhythm / Q000235:genetics / Q000502:physiology; D029721:Drosophila Proteins / Q000502:physiology*; D051860:Fragile X Messenger Ribonucleoprotein 1; D005600:Fragile X Syndrome / Q000235:genetics*; D008969:Molecular Sequence Data; D009043:Motor Activity / Q000235:genetics / Q000502:physiology; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D009457:Neuroglia / Q000378:metabolism / Q000473:pathology / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000473:pathology / Q000502:physiology; D016601:RNA-Binding Proteins; D017386:Sequence Homology, Amino Acid
chemical_list: D029721:Drosophila Proteins; D051860:Fragile X Messenger Ribonucleoprotein 1; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins