Fig. 2. Dsc3 expression throughout mouse development. (A) A northern blot (Seegene, Seoul, Korea) with total RNA from various stages of development was hybridized to a Dsc3 exons 4-8 probe. We obtained only a weak signal at E11.5. (B) RT-PCR analysis with RNA samples from E7.5-E13.5 embryos. RNA from adult mouse skin and kidney served as positive and negative controls, respectively. Band intensity does not necessarily correspond to expression levels in these experiments. (C) RT-PCR using cDNA from E3.5 embryos. Dsc2, Dsc3 and Dsg2 are expressed. Epidermal RNA served as a positive control. (D) Western blot with our Dsc3 antibody, demonstrating that Dsc3a and Dsc3b are both present in total cell lysates from wild-type blastocyst-stage embryos. The blot was stripped and re-probed with ß-catenin antibodies as a control. (E) RT-PCR analysis of E2.5 embryos (pre-compaction stage eight-cell embryos). Two desmosomal cadherins are expressed at this stage: Dsc3 and Dsg2. We also detected mRNA for plakoglobin (PG) and desmoplakin (DP). ß-Actin primers were used as a positive control. (F) RT-PCR with RNA from unfertilized oocytes demonstrating the presence of Dsc3 mRNA. Mouse epidermal RNA served as a positive control. ß-Actin primers were used to confirm the presence of intact cDNA. Blank indicates a negative control, no RNA added.