Fig. 7. The yolk sacs of Hand1^{ß-gal/ß-gal} contain differentiated SMC and express genes required for SMC recruitment. Semi-quantitative RT-PCR was performed with cDNA from extra-embryonic membranes of 8.5 dpc Hand1^+/+ embryos and 9.5 dpc Hand1^{ß-gal/ß-gal} and 9.5 dpc Hand1^+/+ littermates. (A) Analysis of SMC specific differentiation markers. Early and late markers of SMC differentiation were expressed in Hand1^{ß-gal/ß-gal} extra-embryonic membranes. (B) Analysis of SMC migration/recruitment signaling genes. Expression of these genes was not significantly different between wild type and mutant.