Probe:	PN-1 probe1
Probe preparation:	labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS15: neural tube	Present	Regionally restricted	1A	PN-1 transcripts were detected in the ventral neural tube at the met-/mesencephalon junction.
TS15: diencephalon	Present	Regionally restricted	1A	PN-1 mRNA was also observed in the ventral part of the mes- and diencephalon.
TS15: future midbrain	Present	Regionally restricted	1A	PN-1 mRNA was also observed in the ventral part of the mes- and diencephalon.
TS15: otocyst	Present	Regionally restricted	1A	PN-1 mRNA was observed at the surface of the otic vesicle.
TS15: telencephalic vesicle	Absent		1A	Staining in the telencephalic vesicles was considered as an artefact since it could also be observed in control embryos either hybridized with a sense mouse PN-1 riboprobe or without a riboprobe.

Structure	Level	Pattern	Image	Note
TS15: branchial arch	Present	Regionally restricted		PN-1 mRNA was also observed in the posterior, dorsal ectoderm of the paws, in the ectoderm of branchial arches and in the ventral ectodermal ridge of the tail.
TS15: limb	Present	Regionally restricted		PN-1 mRNA was also observed in the posterior, dorsal ectoderm of the paws, in the ectoderm of branchial arches and in the ventral ectodermal ridge of the tail.
TS15: tail	Present	Regionally restricted		PN-1 mRNA was also observed in the posterior, dorsal ectoderm of the paws, in the ectoderm of branchial arches and in the ventral ectodermal ridge of the tail.

Structure	Level	Pattern	Image	Note
TS17: neural tube	Present	Regionally restricted	1B	A band of neuroepithelial cells surrounding the neural tube at the level of the junction between the met- and mesencephalon was observed.
TS17: diencephalon	Present	Regionally restricted	1B	PN-1 mRNA was also observed in the ventral part of the mes- and diencephalon.
TS17: midbrain	Present	Regionally restricted	1B	PN-1 mRNA was also observed in the ventral part of the mes- and diencephalon.

Structure	Level	Pattern	Image	Note
TS19: neural tube	Present	Regionally restricted	1C	PN-1 positive neuroepithelial cells were detected in the neural tube at the mes-/metencephalic junction. In situ hybridization of neighboring sections demonstrated a completely overlapping expression pattern for Fgf8.

Structure	Level	Pattern	Image	Note
TS19: neural tube	Present	Regionally restricted	3F	PN-1 positive neuroepithelial cells were detected in the neural tube at the mes-/metencephalic junction. In situ hybridization of neighboring sections demonstrated a completely overlapping expression pattern for Fgf8.