Fig. 7. Vas-eIF5B interaction is vital for pole cell formation. Pole cells were visualized at the cellular blastoderm stage using either GFP-Vas or immunostaining for Nos protein. The pictures shown are representative for each genotype. (A,B) Using GFP-Vas as a marker in live embryos, pole cells could be detected at the posterior of the majority of vas^PD;P{vas⁺} embryos (A), but in fewer than 1% of vas^PD;P{vas⁶¹⁷} embryos (B). (C) Using immunostaining for Nos as a marker for pole cells, Nos-positive cells could be detected at the posterior in 58% of vas^PD;P{vas⁺} embryos. (D,E) In 81% of vas^PD;P{vas⁶¹⁷} embryos, no Nos-positive cells were apparent at the same stage (D), whereas in 5%, one to three Nos-positive cells could be detected at the posterior (E). (F) In 14% of vas^PD;P{vas⁶¹⁷} embryos, several Nos-positive cells were detected but were positioned elsewhere within the embryo.