Probe:	Tbx1 probe1
Probe preparation:	Antisense labelled with digoxigenin RNA
Assay notes:	After whole-mount staining, embryos were post-fixed in 4% paraformaldehyde/0.2% glutaraldehyde before sectioning.

Structure	Level	Pattern	Image	Note
TS13: embryo mesenchyme	Present	Regionally restricted	6A	Expression was detected in the branchial area, expressed throughout the prechordal mesenchyme. Expression was detected in the mesenchyme beneath the hindbrain and midbrain.

Structure	Level	Pattern	Image	Note
TS13: otic placode	Present	Non-Uniform	6B	Expression was detected in the otic placode. It was slightly stronger in the caudal half.

Structure	Level	Pattern	Image	Note
TS15: branchial arch mesenchyme	Present	Regionally restricted	6C	Expression was restricted to the mesodermal core of the arches.
TS15: otocyst	Very strong		6C

Structure	Level	Pattern	Image	Note
TS15: otocyst	Very strong	Regionally restricted	6D	Expression was restricted to the latero-posterior areas of the vesicle.

Structure	Level	Pattern	Image	Note
TS15: otocyst	Very strong	Regionally restricted	6E	Expression was restricted to the dorsal areas of the vesicle.

Structure	Level	Pattern	Image	Note
TS17: 2nd branchial arch mesenchyme	Present	Regionally restricted	6F	Expression was detected in the mesodermal core of the second, third and fourth arches.
TS17: 3rd branchial arch mesenchyme	Present	Regionally restricted	6F	Expression was detected in the mesodermal core of the second, third and fourth arches.
TS17: 4th branchial arch mesenchyme	Present	Regionally restricted	6F	Expression was detected in the mesodermal core of the second, third and fourth arches.
TS17: 1st branchial arch mesenchyme derived from neural crest	Absent		6F
TS17: 2nd branchial arch mesenchyme derived from neural crest	Absent		6F
TS17: otocyst	Present	Regionally restricted	6F	Expression was detected in the lateral and posterior areas of the vesicle.

Structure	Level	Pattern	Image	Note
TS17: otocyst	Present	Regionally restricted	6G	Expression was detected in the lateral and posterior areas of the vesicle. The anterior border of expression in the lateral wall is very sharp.

Structure	Level	Pattern	Image	Note
TS17: otocyst	Present	Regionally restricted	6H	Expression was detected in the lateral and dorsal areas of the vesicle. The ventral border of expression in the lateral wall is very sharp.