Probe:	Alx4 probe2
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS13: somite	Present		1A
TS13: trunk mesenchyme	Present	Regionally restricted	1A	Expressed in the body wall of the tail region, along the dorsal aorta.
TS13: head mesenchyme	Present	Regionally restricted	1A	Expressed in the cephalic mesenchyme of the prospective craniofacial region.

Structure	Level	Pattern	Image	Note
TS15: face mesenchyme	Present		1B	Strongest expression.
TS15: trunk mesenchyme	Present		1B	Weaker expression in the mesenchyme of the body wall.
TS15: 1st branchial arch	Present		1B
TS15: dorsal aorta	Present		1B
TS15: forelimb bud mesenchyme	Present		1B
TS15: umbilical blood vessel	Present		1B
TS15: somite	Present	Regionally restricted	1B	Expressed in a restricted set of somites (typically somites 5 to 10 in animals with approximately 18-20 somites).

Structure	Level	Pattern	Image	Note
TS15: amnion mesenchyme	Present		5A
TS15: amnion ectoderm	Absent		5A
TS15: yolk sac	Absent		5A

Structure	Level	Pattern	Image	Note
TS15: umbilical cord mesenchyme	Present	Regionally restricted	5B	Expressed in the mesenchymal cells of the umbilical region.