title: The Drosophila fragile X protein functions as a negative regulator in the orb autoregulatory pathway.
abstract: Translational regulation of maternal mRNAs in distinct temporal and spatial patterns underlies many key decisions in developing eggs and embryos. In Drosophila, Orb is responsible for mediating the translational activation of mRNAs localized within the developing oocyte. Orb is a germline-specific RNA binding protein and is one of the founding members of the CPEB family of translational regulators. Here we show that Orb associates with the Drosophila Fragile X Mental Retardation (dFMR1) protein as part of a ribonucleoprotein complex that controls the localized translation of mRNAs in developing egg chambers. One of the key orb regulatory targets is orb mRNA, and this autoregulatory activity is critical for ensuring that Orb protein is expressed at high levels in the oocyte. We show that dFMR1 functions as a negative regulator in the orb autoregulatory circuit, downregulating orb mRNA translation.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Costa
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Dockendorff
authors.forename: Hediye
authors.initials: H
authors.lastname: Erdjument-Bromage
authors.forename: Paul
authors.initials: P
authors.lastname: Tempst
authors.forename: Paul
authors.initials: P
authors.lastname: Schedl
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Jongens
mesh_terms: D000818:Animals; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000378:metabolism; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1; D009865:Oocytes / Q000254:growth & development* / Q000378:metabolism; D009866:Oogenesis / Q000235:genetics / Q000502:physiology*; D011485:Protein Binding; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D051860:Fragile X Messenger Ribonucleoprotein 1; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C467328:FMR1 protein, Drosophila; C089932:orb protein, Drosophila