Probe:	Probe 1
Probe preparation:	labelled with S35 RNA

Structure	Level	Pattern	Image	Note
TS15: future spinal cord	Strong	Regionally restricted	7A	Intense expression in neural crests.
TS15: neural tube	Present	Regionally restricted	7A	Less intense expression extended over dorsal half of neural tube.
TS15: embryo mesenchyme	Present	Regionally restricted	7A	Authors report expression in lateral mesoderm.

Structure	Level	Pattern	Image	Note
TS15: future spinal cord	Strong	Regionally restricted	7B	Intense expression in neural crests
TS15: neural tube	Present	Regionally restricted	7B	Less intense expression extended over dorsal half of neural tube.
TS15: embryo mesenchyme	Present	Regionally restricted	7B	Authors report expression in lateral mesoderm.

Structure	Level	Pattern	Image	Note
TS15: branchial arch	Present	Regionally restricted	7C/D	Expression in restricted parts of the visceral arches.
TS15: 1st branchial arch	Present	Regionally restricted	7C/D	Expression in visceral arch mesenchyme in discrete regions: arch I, cleft between arches II and III, putative position of arch IV.
TS15: 2nd branchial arch	Present	Regionally restricted	7C/D	Expression in visceral arch mesenchyme in discrete regions: arch I, cleft between arches II and III, putative position of arch IV.
TS15: 3rd branchial arch	Present	Regionally restricted	7C/D	Expression in visceral arch mesenchyme in discrete regions: arch I, cleft between arches II and III, putative position of arch IV.
TS15: 1st branchial arch maxillary component	Present	Regionally restricted	7C/D	Intense expression in developing facial connective tissue in the prospective maxillary region.

Structure	Level	Pattern	Image	Note
TS15: forelimb bud	Present	Regionally restricted	7E/F	Restricted pattern of expression in the forelimb and hindlimb buds, with peak expression in the distal and posterior mesenchyme.
TS15: forelimb bud mesenchyme	Strong	Regionally restricted	7E/F	Restricted pattern of expression in the forelimb and hindlimb buds, with peak expression in the distal and posterior mesenchyme.
TS15: embryo mesenchyme	Present	Regionally restricted	7E/F	Authors report expression in lateral mesoderm.

Structure	Level	Pattern	Image	Note
TS15: head mesenchyme derived from neural crest	Strong			Intense expression in the frontal mesenchyme of the head.
TS15: hindlimb ridge	Present	Regionally restricted		Restricted pattern of expression in the forelimb and hindlimb buds, with peak expression in the distal and posterior mesenchyme.