Antibody:	anti-Shh (H-160; sc9024)
Detection system:	Secondary antibody coupled to horseradish peroxidase
Assay notes:	Embryos were fixed in EFA solution--6 volumes 100% ethanol, 3 volumes 37% formaldehyde, and 1 volumes 100% acetic acid.

Structure	Level	Pattern	Image	Note
TS15: future forebrain floor plate	Present		3A , 3A FB floor plate , 3A HB floor plate
TS15: future hindbrain floor plate	Present		3A , 3A FB floor plate , 3A HB floor plate
TS15: future forebrain lateral wall	Absent		3A FB neural fold , 3A HB neural fold , 3A	There is no expression in the dorso-lateral neural folds.
TS15: future hindbrain lateral wall	Absent		3A FB neural fold , 3A HB neural fold , 3A	There is no expression in the dorso-lateral neural folds.
TS15: head mesenchyme	Absent		3A , 3A FB neural fold , 3A HB neural fold	There is no expression in the mesenchyme adjacent to the neural folds.

Structure	Level	Pattern	Image	Note
TS15: future forebrain floor plate	Present		3B , 3B HB floor plate , 3B FB floor plate	In the exencephalic mutants, expression in the floorplate is enhanced compared to what is seen in wild type.
TS15: future hindbrain floor plate	Present		3B , 3B HB floor plate , 3B FB floor plate	In the exencephalic mutants, expression in the floorplate is enhanced compared to what is seen in wild type.
TS15: future forebrain lateral wall	Present		3B FB neural fold , 3B HB neural fold , 3B	In the exencephalic mutants, there is ectopic expression in the neuroepithelium of the dorsolateral neural folds.
TS15: future hindbrain lateral wall	Present		3B FB neural fold , 3B HB neural fold , 3B	In the exencephalic mutants, there is ectopic expression in the neuroepithelium of the dorsolateral neural folds.
TS15: head mesenchyme	Present	Regionally restricted	3B FB neural fold , 3B HB neural fold , 3B	In the exencephalic mutants, there is ectopic expression in the mesenchyme adjacent to the neural folds.

Structure	Level	Pattern	Image	Note
TS15: future forebrain floor plate	Present		3C HB floor plate , 3C , 3C FB floor plate
TS15: future hindbrain floor plate	Present		3C HB floor plate , 3C , 3C FB floor plate
TS15: future forebrain lateral wall	Absent		3C HB neural fold , 3C FB neural fold	In the non-exencephalic mutants, as in wild type, there is no expression in the neuroepithelium of the dorsolateral neural folds.
TS15: future hindbrain lateral wall	Absent		3C HB neural fold , 3C FB neural fold	In the non-exencephalic mutants, as in wild type, there is no expression in the neuroepithelium of the dorsolateral neural folds.
TS15: head mesenchyme	Absent		3C HB neural fold , 3C FB neural fold	In the non-exencephalic mutants, as in wild type, there is no expression in the mesenchyme adjacent to the neural folds.