Probe:	Tbx4 cDNA3
Probe preparation:	Antisense labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS15: forelimb bud	Weak		1P
TS15: hindlimb ridge	Strong		1P	Strong expression in the hindlimb primordium.

Structure	Level	Pattern	Image	Note
TS17: forelimb bud mesenchyme	Weak		1Q	Authors state that differential expression between Tbx4 and Tbx5 in limb mesenchyme is maintained.
TS17: hindlimb bud mesenchyme	Strong		1Q	Authors state that differential expression between Tbx4 and Tbx5 in limb mesenchyme is maintained.

Structure	Level	Pattern	Image	Note
TS19: forelimb bud mesenchyme	Weak		1R	Authors state that differential expression between Tbx4 and Tbx5 in limb mesenchyme is maintained.
TS19: hindlimb bud mesenchyme	Strong		1R	Expression is maintained in the mesenchyme along the entire proximodistal axis.
TS19: future leg mesenchyme	Very strong	Regionally restricted	1R	Locally intense expression in the region where the tibia and fibula are being specified.

Structure	Level	Pattern	Image	Note
TS20: hindlimb mesenchyme	Present	Regionally restricted	1S	In the hindlimb, expression is maintained in the mesenchyme along the entire proximodistal axis.

Structure	Level	Pattern	Image	Note
TS21: hindlimb mesenchyme	Present	Regionally restricted	1T	In the hindlimb, expression is maintained in the mesenchyme along the entire proximodistal axis.

Structure	Level	Pattern	Image	Note
TS19: hindlimb bud mesenchyme	Strong		2E	Strong mesenchymal expression throughout most of the hindlimb.
TS19: footplate apical ectodermal ridge	Absent		2E
TS19: forelimb bud ectoderm	Present		2E	Expression in the forelimb is predominantly a general epithelial signal, not specifically associated with the AER.

Structure	Level	Pattern	Image	Note
TS14: forelimb bud mesenchyme	Absent		3B	No expression in the lateral plate mesoderm of the prospective forelimb field.
TS14: mesenchyme derived from lateral plate	Absent		3B	No expression in the lateral plate mesoderm of the prospective forelimb field.