Antibody:	Dkk-1 Antibody (AF1765)
Detection system:	Secondary antibody

Structure	Level	Pattern	Image	Note
TS7: epiblast	Weak		4B1-1

Structure	Level	Pattern	Image	Note
TS7: epiblast	Weak		4B2-1	Similar as in the wild-type.

Structure	Level	Pattern	Image	Note
TS8: anterior visceral endoderm	Present	Regionally restricted	4B1-2	Expressed in the leading edge of the proximally migrating anterior visceral endoderm.
TS8: epiblast	Present	Regionally restricted	4B1-2	Expressed in the distal part at a lower level.

Structure	Level	Pattern	Image	Note
TS8: epiblast	Strong	Widespread	4B2-2

Structure	Level	Pattern	Image	Note
TS8: anterior visceral endoderm	Present	Regionally restricted	4B1-3	Expressed in the leading edge of the proximally migrating anterior visceral endoderm.
TS8: epiblast	Present	Regionally restricted	4B1-3	Expressed in the distal part at a lower level.

Structure	Level	Pattern	Image	Note
TS8: epiblast	Strong	Widespread	4B2-3

Structure	Level	Pattern	Image	Note
TS9: anterior visceral endoderm	Strong	Regionally restricted	4B1-4	Expressed at the leading edge of the presumptive anterior visceral endoderm, exhibiting a horseshoe-like pattern.

Structure	Level	Pattern	Image	Note
TS9: anterior visceral endoderm	Strong		4B2-4	Expression was more abundant, with an expanded region.

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4C upper left

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4C upper right

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4C lower left

Structure	Level	Pattern	Image	Note
TS9: embryo ectoderm	Strong		4C lower right
TS9: primitive endoderm	Strong		4C lower right

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4D upper left

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4D upper right

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		4D lower left	A significant amount of expression had accumulated in the extracellular space.

Structure	Level	Pattern	Image	Note
TS9: embryo ectoderm	Present		4D lower right	A significant amount of expression had accumulated in the extracellular space.
TS9: primitive endoderm	Present		4D lower right	A significant amount of expression had accumulated in the extracellular space.

Structure	Level	Pattern	Image	Note
TS8: primitive endoderm	Present		5A1-1 , 5A1-3 , 5A1-2 , 5A1-4	Intracellular expressed in early endosomes, coexpressed with Snx1.

Structure	Level	Pattern	Image	Note
TS8: primitive endoderm	Present		5A2-4 , 5A2-2 , 5A2-1 , 5A2-3	Accumulate outside the basal membrane, not coexpressed with Snx1.

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		5B1-2 , 5B1-1 , 5B1-3	Some internalized Dkk1 at the apical side were positive for immunoglobulins.

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		5B2-2 , 5B2-3 , 5B2-1	Some internalized Dkk1 at the apical side were positive for Lamp2.

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		S3upper left , S3upper right , S3upper middle	Existed in close proximity with Rab4a, which expressed in a resident of subdomains of early endosomes.

Structure	Level	Pattern	Image	Note
TS9: primitive endoderm	Present		S3lower left , S3lower right , S3lower middle	Existed separately with Rab4a, which expressed in a resident of subdomains of early endosomes.