Reduction in fragile X related 1 protein causes cardiomyopathy and muscular dystrophy in zebrafish.

Lack of the FMR1 gene product causes fragile X syndrome, the commonest inherited cause of mental impairment. We know little of the roles that fragile X related (FXR) gene family members (FMR1, FXR2 and FXR1) play during embryonic development. Although all are expressed in the brain and testis, FXR1 is the principal member found in striated and cardiac muscle.

Lessons from BWS twins: complex maternal and paternal hypomethylation and a common source of haematopoietic stem cells.

The Beckwith-Wiedemann syndrome (BWS) is a growth disorder for which an increased frequency of monozygotic (MZ) twinning has been reported. With few exceptions, these twins are discordant for BWS and for females. Here, we describe the molecular and phenotypic analysis of 12 BWS twins and a triplet; seven twins are MZ, monochorionic and diamniotic, three twins are MZ, dichorionic and diamniotic and three twins are dizygotic.

Two members of the Fxr gene family, Fmr1 and Fxr1, are differentially expressed in Xenopus tropicalis.

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.

Characterisation of Fmrp in zebrafish: evolutionary dynamics of the fmr1 gene.

Fragile X syndrome is the most common inherited form of mental retardation. It is caused by the lack of the Fragile X Mental Retardation Protein (FMRP), which is encoded by the FMR1 gene. Although Fmr1 knockout mice display some characteristics also found in fragile X patients, it is a complex animal model to study brain abnormalities, especially during early embryonic development.

Transport kinetics of FMRP containing the I304N mutation of severe fragile X syndrome in neurites of living rat PC12 cells.

Lack of fragile X mental retardation protein (FMRP) causes the fragile X syndrome, a common form of inherited mental retardation. The syndrome usually results from the expansion of a CGG repeat in the FMR1 gene with consequent transcriptional silencing of FMR1. However, one missense mutation (Ile304Asn) was reported in the second KH domain of the protein involved in RNA binding.

Characterization of Fxr1 in Danio rerio; a simple vertebrate model to study costamere development.

The X-linked FMR1 gene, which is involved in the fragile X syndrome, forms a small gene family with its two autosomal homologs, FXR1 and FXR2. Mouse models for the FXR genes have been generated and proved to be valuable in elucidating the function of these genes, particularly in adult mice. Unfortunately, Fxr1 knockout mice die shortly after birth, necessitating an animal model that allows the study of the role of Fxr1p, the gene product of Fxr1, in early embryonic development.