Fig. 4. RT-PCR analysis of angiogenic genes in Hand1^{ß-gal/ß-gal} and Hand1^+/+ extra-embryonic membranes. cDNA was synthesized from RNA extracted from the individual extraembryonic membranes of 8.5 dpc Hand1^+/+ embryos and 9.5 dpc Hand1^{ß-gal/ß-gal} and 9.5 dpc Hand1^+/+ littermates. Semi-quantitative RT-PCR was performed with synthesized cDNA. Expression of growth factor Vegf and its receptors are shown on the left (top). Expression of angiogenic growth factor Ang1 and its receptors are shown on the left (bottom). Expression of Hand1 was monitored to confirm our genotype analysis. Expression of related bHLH factor Hand2 was also examined. Vegf, Flt1, Flk1, Npr1, Ang1, Efnb2, Bmp4, Notch1, Notch4, Hey1 and Hand2 were upregulated in Hand1^{ß-gal/ß-gal} extraembryonic membranes. Gapd was used to normalize each sample.