Fig. 1

rbm24a and rbm24b are expressed throughout somitogenesis.

ISH images of uninjected AB embryos using rbm24a or rbm24b riboprobes individually marking spatial and temporal RNA expression. Tailbud expression of bud stage embryos in lateral-slightly ventral facing (A, C) and dorsal (B, D) orientations. 8 somite embryos in dorsal facing orientations show all segmented somites (E, G) and PSM (F, H) marked by rbm24a and rbm24b riboprobes. Trunk images of embryos at 24 hpf show spatial expression of rbm24a in the somites concentrated at the posterior, while rbm24b is uniformly expressed in somites along the A-P axis (I-J). Inset of (I-J) highlights expression of rbm24a and rbm24b in the PSM. Embryos at 48 hpf show no somite rbm24a expression, while somite expression of rbm24b remains uniform thought the somites (K-L). som, somites; hpf, hours post fertilization; arrows, tailbud expression; A, anterior of embryo; P, posterior of embryo; bracket, PSM expression.