Notch1lbd/lbdmaternal and zygotic null embryos. (A) PCR of genomic DNA using primers 5F and 6R (Fig. 1A), and ZP3Cre primers. N1F: Notch1 floxed allele; Cre: ZP3Cre transgene. (B) – (C) E9.5 yolk sac with embryos from crosses between Notch1F/F:ZP3Cre females and Notch1+/lbdmales. (D) – (E) E8.75 Notch1+/lbdand Notch1lbd/lbdembryos. (F) – (G) E9.5 Notch1+/lbdand Notch1lbd/lbdembryos. Representative results from a total of 14 E8.75 embryos and 29 E9.5 embryos.