A Ubiquitous expression of Sumo1, Sumo2, and Sumo3 in E7.5, E8.5, and E9.5 wild-type embryos. Whole-mount in situ hybridization analysis of Sumo1, Sumo2, and Sumo3 expression was performed in C57BL/6 wild-type mouse embryos. The specificity of all probes was validated by comparing whole-mount in situ hybridization in wild-type to Sumo1-, Sumo2-, and Sumo3-null embryos, as demonstrated in Supplementary Fig S1. Scale bars: 100 μm (left panel), 500 μm (right panel).
B Targeting strategy for Sumo2 and Sumo3. The targeting vectors were designed to disrupt exon 1 by in-frame insertion of 2 stop codons and a neomycin (NEO) cassette downstream of the ATG codon. Arrowheads mark the location of primers for genotyping. Gray boxes show exons. TK, thymidine kinase cassette.
C Representative genotyping results of embryos obtained from timed Sumo2+/− or Sumo3+/− intercrosses. Genomic DNA prepared from extraembryonic tissue was used for PCR amplification with primers as described in (B) and Supplementary Table S1.
D Normal Mendelian distribution of newborn pups from Sumo3+/− intercrosses.
E Summary of genotyping analysis of staged embryos from Sumo2+/− intercrosses.
F Representative image of Sumo2 expression by whole-mount in situ hybridization in a wild-type embryo (control, left) and a homozygous null embryo (Sumo2−/−, right) at E7.5. Scale bar: 100 μm.