Unusual misregulation of RNA splicing caused by insertion of a transposable element into the T (Brachyury) locus.
BACKGROUND
The TWis mutant allele of the Brachyury, or T, gene was created by insertion of an endogenous retrovirus-like early transposon (ETn) element into the exon 7 splice donor consensus sequence of the 8 exon T locus. While the developmental consequences of this disruption have been well characterized, the molecular consequences have not been previously investigated, and it has been assumed that the insertion results in a truncated protein. This study sought to further characterize the mutant TWis allele by investigating the nature of the transcripts produced by insertion of this transposable element.


RESULTS
Using an RT-PCR based approach, we have shown that at least 8 different mutant transcripts are produced from the TWis allele. All TWis transcripts bypass the mutated exon 7 splice donor site, such that wild type T transcripts are not produced from the TWis allele.


CONCLUSIONS
This result shows an unsuspected misregulation of RNA splicing caused by insertion of a transposable element, that could have more widespread consequences in the genome.
Goldin
Sarah N
SN
Department of Genetics and Development, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA. sgoldin@darbylaw.com
Papaioannou
Virginia E
VE
D000483:Alleles; D000818:Animals; D004622:Embryo, Mammalian; D005314:Embryonic and Fetal Development / Q000235:genetics; D005091:Exons / Q000235:genetics; D005326:Fetal Proteins / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D017781:Genes, Immediate-Early / Q000235:genetics; D008648:Mesoderm / Q000737:chemistry / Q000378:metabolism; D051379:Mice; D020297:Mice, Congenic; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D022821:RNA Splice Sites / Q000235:genetics; D012326:RNA Splicing / Q000235:genetics*; D018626:Retroelements / Q000235:genetics*; D020825:T-Box Domain Proteins / Q000172:deficiency / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics; D000098908:Brachyury Protein
D005326:Fetal Proteins; D022821:RNA Splice Sites; D018626:Retroelements; D020825:T-Box Domain Proteins; D000098908:Brachyury Protein