Probe:	Cerr1 cDNA3
Probe preparation:	Antisense labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS9: anterior visceral endoderm	Present	Regionally restricted	3A	Expression is present in the anterior visceral endoderm. (The expression domain extends from the extraembryonic-embryonic junction to approximately two thirds of the way down the epiblast.)

Structure	Level	Pattern	Image	Note
TS10: anterior visceral endoderm	Present		3B
TS10: definitive endoderm	Present	Regionally restricted	3B	Expression is present in the defintive endoderm emanating from the anterior portion of the primitive streak.

Structure	Level	Pattern	Image	Note
TS11: embryo	Present	Regionally restricted	3C	Expression is present in the anterior and anterior lateral portion of the embyro. It is not present in the anterior-most lateral region that appears to correspond to the presumptive cardiac region.
TS11: embryo endoderm	Present	Regionally restricted	3C	Expression is present throughout the anterior definitive endoderm, including both the midline and anterior lateral endoderm.

Structure	Level	Pattern	Image	Note
TS11: embryo endoderm	Present	Regionally restricted	3D	Expression is present in the anterior endoderm layer.

Structure	Level	Pattern	Image	Note
TS11: embryo	Present	Regionally restricted	3E	Expression is present in the midline and anterior lateral region but excluded from the presumptive cardiac region.
TS11: embryo endoderm	Present	Regionally restricted	3E	Expression is present throughout the anterior definitive endoderm, including both the midline and anterior lateral endoderm.
TS11: heart	Absent		3E

Structure	Level	Pattern	Image	Note
TS11: embryo endoderm	Present		3F	Expression is localized to the foregut endoderm. It is reduced in the anterior lateral region.

Structure	Level	Pattern	Image	Note
TS13: somite	Present	Regionally restricted	3G	Expression is expressed exclusively in the two most newly-formed somites.

Structure	Level	Pattern	Image	Note
TS14: trunk somite	Present	Regionally restricted	3H	Expression is expressed in the two most newly-formed somites.
TS14: trunk unsegmented mesenchyme	Present	Regionally restricted	3H	Expression is present in the anterior portion of the presomitic mesoderm.

Structure	Level	Pattern	Image	Note
TS10: embryo endoderm	Present		5A left

Structure	Level	Pattern	Image	Note
TS10: anterior visceral endoderm	Absent		5A right	In the vast majority of embryos examined there was no expression (or there was weak expression in a few scattered cells in the presumptive anterior visceral endoderm and the definitive endoderm regions).
TS10: definitive endoderm	Absent		5A right	In the vast majority of embryos examined there was no expression (or there was weak expression in a few scattered cells in the presumptive anterior visceral endoderm and the definitive endoderm regions).

Structure	Level	Pattern	Image	Note
TS10: anterior visceral endoderm	Weak	Single cells		There was weak expression in a few scattered cells in the presumptive anterior visceral endoderm and the definitive endoderm regions (in the central portion of the epiblast and near the distal tip region). (In many cases there was no expression.)
TS10: definitive endoderm	Weak	Single cells		There was weak expression in a few scattered cells in the presumptive anterior visceral endoderm and the definitive endoderm regions (in the central portion of the epiblast and near the distal tip region). (In many cases there was no expression.)

Structure	Level	Pattern	Image	Note
TS10: embryo	Present	Regionally restricted	5B	In two embryos strong expression was seen in a patch of cells just anterior to the primitive streak.