The generation of a conditional Fmr1 knock out mouse model to study Fmrp function in vivo

Neurobiol Dis. 2006 Mar;21(3):549-55. doi: 10.1016/j.nbd.2005.08.019. Epub 2005 Oct 26.

Abstract

The FMR1 gene, mutated in Fragile X syndrome patients, has been modeled in mice with a neomycin cassette inserted in exon 5 of the mouse Fmr1 gene creating an Fmr1 knockout (Fmr1 KO) allele. This results in animals lacking Fmr1 protein (Fmrp) expression in all tissues. We have created a new, more versatile Fmr1 in vivo KO model (Fmr1 KO2) and generated conditional Fmr1 KO (CKO) mice by flanking the promoter and first exon of Fmr1 with lox P sites. This enables us to create a null allele in specific cell types and at specific time points by crossing Fmr1 CKO mice with tissue specific or inducible cre-recombinase expressing mice. The new Fmr1 KO2 line does not express any Fmrp and also lacks detectable Fmr1 transcripts. Crossing the Fmr1 CKO line with a Purkinje cell-specific cre-recombinase expresser produces mice that are null for Fmr1 in Purkinje neurons but wild type in all other cell types.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Disease Models, Animal*
  • Fragile X Mental Retardation Protein / genetics*
  • Fragile X Syndrome / genetics
  • Fragile X Syndrome / metabolism
  • Immunohistochemistry
  • Mice
  • Mice, Knockout
  • Purkinje Cells / physiology*
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Fmr1 protein, mouse
  • Fragile X Mental Retardation Protein