Journal Article

Knockout mouse model for <i>Fxr2</i>: a model for mental retardation

Carola J. M. Bontekoe, Kellie L. McIlwain, Ingeborg M. Nieuwenhuizen, Lisa A. Yuva-Paylor, Anna Nellis, Rob Willemsen, Zhe Fang, Laura Kirkpatrick, Cathy E. Bakker, Robin McAninch, Ngan Ching Cheng, Michelle Merriweather, Andre T. Hoogeveen, David Nelson, Richard Paylor and Ben A. Oostra

in Human Molecular Genetics

Volume 11, issue 5, pages 487-498
Published in print March 2002 | ISSN: 0964-6906
Published online March 2002 | e-ISSN: 1460-2083 | DOI:
Knockout mouse model for Fxr2: a model for mental retardation

Show Summary Details


Fragile X syndrome is a common form of mental retardation caused by the absence of the FMR1 protein, FMRP. Fmr1 knockout mice exhibit a phenotype with some similarities to humans, such as macro-orchidism and behavioral abnormalities. Two homologs of FMRP have been identified, FXR1P and FXR2P. These proteins show high sequence similarity, including all functional domains identified in FMRP, such as RNA binding domains. They have an overlap in tissue distribution to that of FMRP. Interactions between the three FXR proteins have also been described. FXR2P shows high expression in brain and testis, like FMRP. To study the function of FXR2P, we generated an Fxr2 knockout mouse model. No pathological differences between knockout and wild-type mice were found in brain or testis. Given the behavioral phenotype in fragile X patients and the phenotype previously reported for the Fmr1 knockout mouse, we performed a thorough evaluation of the Fxr2 knockout phenotype using a behavioral test battery. Fxr2 knockout mice were hyperactive (i.e. traveled a greater distance, spent more time moving and moved faster) in the open-field test, impaired on the rotarod test, had reduced levels of prepulse inhibition, displayed less contextual conditioned fear, impaired at locating the hidden platform in the Morris water task and were less sensitive to a heat stimulus. Interestingly, there are some behavioral phenotypes in Fxr2 knockout mice which are similar to those observed in Fmr1 knockout mice, but there are also some different behavioral abnormalities that are only observed in the Fxr2 mutant mice. The findings implicate a role for Fxr2 in central nervous system function.

Journal Article.  8145 words.  Illustrated.

Subjects: Genetics and Genomics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.