Xenbase Image ID: 49824

Fig. 3. Xdm maps to a transgene insertion in nephronectin. (A) Schematic showing the wild type npnt genomic locus (above), and the structure of the Nkx2.5FP transgene insertion in the xdm allele (below). Genotyping primers which amplify the wild type npnt allele (NF + NR) and the junctions at each end of the insertion (NR + TR and TF + NR) are indicated. (B) Npnt sequence spanning the insertion can be amplified with npnt primers (NF + NR) from wild type (wt) but not transgenic (tgn) haploid embryos; chimaeric DNA at either end of the insertion can be amplified from transgenic but not wild type haploids using an npnt primer with a transgene primer (NF + TR and TF + NR). (C) Genotyping wild type and forelimbless siblings from an xdm cross with NF + NR and NF + TR shows that the xdm phenotype is tightly linked to the transgene insertion; sample of 14 shown (175 total genotyped). (D) Npnt mRNA is truncated by the transgene insertion. Top panel, 5 transgenic and 2 non-transgenic st. 40 tadpoles genotyped as in (C). Asterisk (left lane) marks heterozygous transgenic tadpole. RT-PCR (2nd and 3rd panels) shows that npnt message upstream of transgene insertion (exons 1) appears reduced in homozygous xdm tadpoles compared to heterozygous or wild type, while exons downstream of the insertion (exons 4) are not detected. See Fig. S1 for sequences across junctions of npnt intron and transgene. (E) The truncated protein encoded by the xdm allele lacks the 5 EGF-like domains, the RGD/linker, and the MAM domain of nephronectin. Image published in: Abu-Daya A et al. (2011) © 2011 Elsevier Inc. This image is reproduced with permission of the journal and the copyright holder. This is an open-access article distributed under the terms of the Creative Commons Attribution license Larger Image Printer Friendly View

Return to previous page