Probe:	Hoxb4 cDNA3
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS15: foregut	Present	Regionally restricted	1A b4	Anterior boundary is the fourth branchial arch. Higher levels at the level of the lung buds and caudally.
TS15: midgut	Present	Regionally restricted	1A b4	Expression extends caudially to the region from which the liver develops.

Structure	Level	Pattern	Image	Note
TS17: lung mesenchyme	Present	Uniform	2_E10.5 b4
TS17: main bronchus mesenchyme	Present	Uniform	2_E10.5 b4
TS17: trachea mesenchyme	Present	Uniform	2_E10.5 b4
TS17: lung epithelium	Absent		2_E10.5 b4
TS17: main bronchus epithelium	Absent		2_E10.5 b4
TS17: trachea epithelium	Absent		2_E10.5 b4

Structure	Level	Pattern	Image	Note
TS19: lung mesenchyme	Present	Uniform	2_E11.5 b4
TS19: main bronchus mesenchyme	Present	Uniform	2_E11.5 b4
TS19: trachea mesenchyme	Present	Uniform	2_E11.5 b4
TS19: lung epithelium	Absent		2_E11.5 b4
TS19: main bronchus epithelium	Absent		2_E11.5 b4
TS19: trachea epithelium	Absent		2_E11.5 b4

Structure	Level	Pattern	Image	Note
TS20: carina trachea mesenchyme	Strong		2_E12.5 b4
TS20: trachea	Present		2_E12.5 b4

Structure	Level	Pattern	Image	Note
TS19: lung mesenchyme	Present		3
TS19: lung epithelium	Absent		3

Structure	Level	Pattern	Image	Note
TS22: lung mesenchyme	Present
TS22: lung epithelium	Absent