Reduced expression of fukutin related protein in mice results in a model for fukutin related protein associated muscular dystrophies.
Mutations in fukutin related protein (FKRP) are responsible for a common group of muscular dystrophies ranging from adult onset limb girdle muscular dystrophies to severe congenital forms with associated structural brain involvement, including Muscle Eye Brain disease. A common feature of these disorders is the variable reduction in the glycosylation of skeletal muscle alpha-dystroglycan. In order to gain insight into the pathogenesis and clinical variability, we have generated two lines of mice, the first containing a missense mutation and a neomycin cassette, FKRP-Neo(Tyr307Asn) and the second containing the FKRP(Tyr307Asn) mutation alone. We have previously associated this missense mutation with a severe muscle-eye-brain phenotype in several families. Homozygote Fkrp-Neo(Tyr307Asn) mice die soon after birth and show a reduction in the laminin-binding epitope of alpha-dystroglycan in muscle, eye and brain, and have reduced levels of FKRP transcript. Homozygous Fkrp(Tyr307Asn) mice showed no discernible phenotype up to 6 months of age, contrary to the severe clinical course observed in patients with the same mutation. These results suggest the generation of a mouse model for FKRP related muscular dystrophy requires a knock-down rather than a knock-in strategy in order to give rise to a disease phenotype.
Ackroyd
M R
MR
Department of Cellular and Molecular Neuroscience, Hammersmith Hospital, Imperial College, London, UK.
Skordis
L
L
Kaluarachchi
M
M
Godwin
J
J
Prior
S
S
Fidanboylu
M
M
Piercy
R J
RJ
Muntoni
F
F
Brown
S C
SC
D000818:Animals; D015139:Blotting, Southern; D002465:Cell Movement; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology; D002678:Chimera; D049030:Dystroglycans / Q000378:metabolism; D005260:Female; D018390:Gene Targeting; D005838:Genotype; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D023421:Models, Animal; D009136:Muscular Dystrophies / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D020125:Mutation, Missense; D010430:Pentosyltransferases; D010641:Phenotype; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014166:Transferases
D011506:Proteins; D049030:Dystroglycans; D014166:Transferases; C499093:Fkrp protein, mouse; D010430:Pentosyltransferases