Probe:	Pax3 probe2
Probe preparation:	labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase
Assay notes:	Embryos were fixed in gluteraldehyde/paraformaldehyde (0.2%/0.4%).

Structure	Level	Pattern	Image	Note
TS15: trunk somite	Present	Regionally restricted	1A	Pax-3 expression was evenly distributed over newly formed somites, whereas at later stages of somitic development the Pax-3 signal was confined to the most caudal and ventrolateral edge in each somite.
TS15: forelimb bud	Present		1A

Structure	Level	Pattern	Image	Note
TS16: trunk somite	Present	Regionally restricted	1C , 1B	Pax-3 expression was evenly distributed over newly formed somites, whereas at later stages of somitic development the Pax-3 signal was confined to the most caudal and ventrolateral edge in each somite.
TS16: forelimb bud	Present		1B , 1C

Structure	Level	Pattern	Image	Note
TS19: trunk somite	Present	Regionally restricted	1E , 1D	Pax-3 signal was clustered in the ventrolateral bud appearing in individual somites of the trunk. A clearly weaker expression domain was observed more dorsomedially in two parallel stripes along the anterior and posterior borders of each somite.

Structure	Level	Pattern	Image	Note
TS15: trunk somite	Present	Regionally restricted	1F	While the Pax-3 signal in early somites appeared similar to wild-type, no local redistribution to the ventrolateral part occurred in the more advanced somites.
TS15: forelimb bud	Absent		1F

Structure	Level	Pattern	Image	Note
TS16: trunk somite	Present	Regionally restricted	1H , 1G	The somitic area normally labelled by Pax-3 appeared much shorter and disorganized in mutant embryos.
TS16: forelimb bud	Absent		1H , 1G

Structure	Level	Pattern	Image	Note
TS19: trunk somite	Present	Regionally restricted	1J , 1I	The somitic area normally labelled by Pax-3 appeared much shorter and disorganized. The edges of the somites delineated by the Pax-3 signal appeared irregular. The Pax-3 expression domain was slightly shifted ventrally, away from the neural tube.

Structure	Level	Pattern	Image	Note
TS15: forelimb bud	Present	Regionally restricted	2A	The early distribution of Pax-3 signal appeared to be compact.

Structure	Level	Pattern	Image	Note
TS15: forelimb bud	Present	Regionally restricted	2B	The early distribution of Pax-3 signal appeared to be compact.

Structure	Level	Pattern	Image	Note
TS16: forelimb bud	Present	Regionally restricted	2C	Pax-3 signal displayed a more scattered distribution at later stages.

Structure	Level	Pattern	Image	Note
TS16: forelimb bud	Present	Regionally restricted	2D	Pax-3 signal displayed a more scattered distribution at later stages.

Structure	Level	Pattern	Image	Note
TS16: forelimb bud	Absent		2E

Structure	Level	Pattern	Image	Note
TS16: forelimb bud	Absent		2F

Structure	Level	Pattern	Image	Note
TS15: trunk somite	Present	Regionally restricted	3A	The early Pax-3 expression seemed to be confined to the dermomyotomal cap of the somites.

Structure	Level	Pattern	Image	Note
TS16: embryo	Present	Regionally restricted	3B	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, and accumulate at the body-limb junction.
TS16: trunk somite	Present	Regionally restricted	3B	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, and accumulate at the body-limb junction.

Structure	Level	Pattern	Image	Note
TS17: embryo	Present	Regionally restricted	3C	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, accumulate at the body-limb junction and then further invade the limbs.
TS17: hindlimb bud	Present	Regionally restricted	3C	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, accumulate at the body-limb junction and then further invade the limbs.
TS17: trunk somite	Present	Regionally restricted	3C	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, accumulate at the body-limb junction and then further invade the limbs.

Structure	Level	Pattern	Image	Note
TS15: embryo	Present	Regionally restricted	3D	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, accumulate at the body-limb junction and then further invade the limbs.
TS15: forelimb bud	Present	Regionally restricted	3D	As the dermomyotomal cap elongated ventrolaterally, cells appeared to detach from the somitic domain, accumulate at the body-limb junction and then further invade the limbs.

Structure	Level	Pattern	Image	Note
TS16: forelimb bud	Present	Regionally restricted	3E	The Pax-3-expressing cell population segregated into dorsally and ventrally located domains.

Structure	Level	Pattern	Image	Note
TS17: forelimb bud	Present	Regionally restricted	3F	The Pax-3-expressing cell population segregated into dorsally and ventrally located domains.

Structure	Level	Pattern	Image	Note
TS15: neural tube	Strong		3G
TS15: trunk somite	Strong	Regionally restricted	3G	Pax-3 expression was strong in the dermomyotome of splotch embryos.

Structure	Level	Pattern	Image	Note
TS16: neural tube	Strong		3H
TS16: trunk somite	Strong	Regionally restricted	3H	Pax-3 expression was strong in the dermomyotome of splotch mutants.

Structure	Level	Pattern	Image	Note
TS17: neural tube	Strong		3I
TS17: trunk somite	Strong	Regionally restricted	3I	Pax-3 expression was strong in the dermomyotome of splotch mutants.