Molecular signalling is disturbed in <i>Ift140^cauli/cauli</i> embryos.

<p>WISH analysis of the forelimbs and hindlimbs of <i>Ift140^+/+</i> and <i>Ift140^cauli/cauli</i> embryos. Dorsal view of fore- and hindlimb buds (A–J′), where anterior is always to the top of the image. Distal view of forelimb buds (K′–M′), where dorsal side is facing to the right of the image. Arrowhead in (C) indicates ectopic <i>Shh</i> expression domain. Bars in (J,L and M′,N′) indicate anterior-posterior extent of <i>Grem1</i> expression. Arrowhead in (K) indicates disruption in <i>Grem1</i> expression in mutant forelimb. Asterisk in (W and X) indicates elevated anterior <i>Dusp6</i> expression. Arrow, arrowhead and asterisk in J′ indicate a single ectopic digit, bifid ectopic digit and proximal syndactyly respectively. A, anterior; P, posterior; D, dorsal; V, ventral; FL, forelimb; HL, hindlimb. All embryos are E11.5 except G′–J′ which are E13.5.