(A) In situ hybridizations of Foxa.a in early Ciona embryos injected with MOs targeting Hes.a, Ccnb3, and Pem individually or in combination.
(B) In situ hybridizations of Tfap2-r.b under the same experimental conditions as A.
(C) In situ hybridizations of Foxd.b with BIO treatments and Ccnb3 or Ccnb3 + Pem targeting MO injections. Expression in cells matching controls are indicated with a white arrowhead. The expansion of expression into additional cells is indicated with a yellow arrowhead. Precocious expression is indicated with a red arrowhead. Embryos are orientated anterior left. Scale bar = 50 µm. See also Figures S2–S3.