Figure 4

Quantitative analysis of growth factor expression levels in response to excess embryonic Cdkn1c. A) Quantitative RT-PCR data for Igf1 on whole embryos from lines 5D3 and 5A4. At E11.5, there is a slight reduction in Igf1 in the two-copy line. At E13.5, there is a reduction in Igf1 levels in both lines. B) Quantitative RT-PCR data for Igf2 on whole embryos from lines 5D3 and 5A4. At E11.5, there is a slight increase in Igf2 in both lines while at E13.5, there is a significant decrease in Igf2 in the two-copy line. C) Comparison of expression of Igf1 at E12.5 in the single copy line, 5D3, head compared with body and whole Cdkn1c null embryos. In line 5D3, Igf1 levels are 60% less than wild type levels in the head where transgenic Cdkn1c is predominantly expressed but relatively unaffected in the body. In null embryos, Igf1 levels are raised by three-fold in the head. D) Comparison of expression of Igf2 at E12.5. In line 5D3, Igf2 levels are raised by two-fold in the head but 50% wild type levels in the body. In null embryos, Igf2 levels are similar to wild type.