title: Two members of the Fxr gene family, Fmr1 and Fxr1, are differentially expressed in Xenopus tropicalis.
abstract: The Fxr gene family is composed of three members, FMR1, FXR1 and FXR2. The FMR1 gene is involved in the fragile X syndrome, whereas for the other two members, no human disorder has been identified yet. An appropriate animal model to study in vivo gene function is essential to unravel the cellular function of the gene products FMRP, FXR1P and FXR2P, respectively. In Xenopus tropicalis both Fmr1 and Fxr1 were identified; however, unexpectedly Fxr2 was not. Here we describe the characterization of both Fmrp and Fxr1p in Xenopus tropicalis. Fmrp is expressed ubiquitously throughout the embryo during embryonic development, whereas Fxr1p shows a more tissue-specific expression particularly during late embryonic development. In adult frogs both proteins are highly expressed in most neurons of the central nervous system and in all spermatogenic cells in the testis. In addition, Fxr1p is also highly expressed in striated muscle tissue. Western blotting experiments revealed only one prominent isoform for both proteins using different tissue homogenates from adult frogs. Thus, for in vivo gene function studies, this relative simple animal model may serve as a highly advantageous and complementary model.
authors.affiliation: CBG Dept. of Clinical Genetics, Erasmus MC Rotterdam, The Netherlands.
authors.forename: Lau
authors.initials: L
authors.lastname: Blonden
authors.forename: Sandra
authors.initials: S
authors.lastname: van 't Padje
authors.forename: Lies-Anne
authors.initials: LA
authors.lastname: Severijnen
authors.forename: Olivier
authors.initials: O
authors.lastname: Destree
authors.forename: Ben A
authors.initials: BA
authors.lastname: Oostra
authors.forename: Rob
authors.initials: R
authors.lastname: Willemsen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005600:Fragile X Syndrome / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D017403:In Situ Hybridization; D008607:Intellectual Disability / Q000235:genetics*; D023421:Models, Animal; D008969:Molecular Sequence Data; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014981:Xenopus / Q000235:genetics*; D029867:Xenopus Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D051860:Fragile X Messenger Ribonucleoprotein 1; D016601:RNA-Binding Proteins; D029867:Xenopus Proteins; C497683:FMR1 protein, human; C505711:FXR1 protein, Xenopus; C096916:FXR1 protein, human; C497686:Fmr1 protein, Xenopus