TY - JOUR TI - Essential validation of gene trap mouse ES cell lines: a test case with the gene Ttrap AU - Vermeire, Liesbeth AU - Ibrahimi, Abdelilah AU - Voet, Thierry AU - Umans, Lieve AU - Coddens, Kathleen AU - Francis, Annick AU - Van de putte, Tom AU - van Grunsven, LeoA. AU - Zwijsen, An AU - Huylebroeck, Danny AU - Nelles, Luc T2 - The International Journal of Developmental Biology AB - Gene trapping in mouse embryonic stem (ES) cells enables near-saturation vector-based insertional mutagenesis across the genome of this model organism. About 135,000 trapped ES cell lines are made available to the scientific community by the International Gene Trap Consortium (IGTC; www.genetrap.org). A search of one of its databases identified an ES cell line (RRS512) with a betaGeo-based gene trap (gt) vector insertion in intron 5 of Ttrap, a gene that encodes an intracellular signalling protein, which is implicated in gastrulation movement and left-right asymmetry in zebrafish embryos. We have determined the exact gt insertion point in the mutant ES cell clone RRS512 and confirmed the production of a chimaeric transcript consisting of the upstream Ttrap exons and the gene trap vector encoded marker/selection fusion sequences. This ES cell line was used to generate heterozygous Ttrap mutant mice, which were further crossed to obtain Ttrapgt/gt mice. In contrast to Ttrap’s documented essential role during nodal and Smad3 controlled zebrafish early embryogenesis, Ttrapgt/gt mice were born with a normal Mendelian distribution. However, subsequent analysis of these Ttrapgt/gt mice has revealed a duplication of the wild-type Ttrap allele that was already present in the RRS512 cell line. Based on our detailed analysis presented here, we suggest an extensive procedure for the characterization of gene trap ES cell lines prior to generating gene trap mice with these. PY - 2009 DO - 10.1387/ijdb.092859lv VL - 53 IS - 7 SP - 1045 EP - 1051 J2 - Int. J. Dev. Biol. LA - en SN - 0214-6282 SN - 1696-3547 UR - https://ijdb.ehu.eus/article/092859lv Y2 - 2024/05/01/06:09:35 ER -