Antibody:	Anti-Stella/Dppa3 AF2566
Detection system:	Secondary antibody coupled to DyLight 549

Structure	Level	Pattern	Image	Note
TS11: allantois mesoderm	Present	Regionally restricted	2D , 2B	Expression in Allantoic Core Domain (ACD). All expressing cells co-expressed Oct-3/4 (Pou5f1), but Stella expression was absent in some Oct-3/4-expressing cells.

Structure	Level	Pattern	Image	Note
TS12: allantois mesenchyme	Present	Regionally restricted	2H , 2F	Expression in remnant of Allantoic Core Domain (ACD) distal to invaginating hindgut with cells co-expressing Oct-3/4 (Pou5f1). Expression throughout nucleus, including perinucleus and core. Some expression independent of nucleus.

Structure	Level	Pattern	Image	Note
TS13: allantois mesenchyme	Present	Regionally restricted	2J , 2L	Co-expression with Oct-3/4 (Pou5f1) in cell cluster at midline base of allantois, with expression throughout nucleus, including perinucleus and core. Occasional co-expressing cells moving away from cluster, toward distal region of allantois.

Structure	Level	Pattern	Image	Note
TS11: posterior visceral endoderm	Present	Regionally restricted	3B , 3D	Co-expression with Oct-3/4 (Pou5f1) in cells throughout allantois-associated posterior visceral endoderm (aPVE), with expression throughout nucleus, including perinucleus and core. Some Oct-3/4-expressing cells are absent for Stella (Dppa3) expression.

Structure	Level	Pattern	Image	Note
TS12: posterior visceral endoderm	Present	Regionally restricted		Co-expression with Oct-3/4 (Pou5f1) in cells of allantois-associated posterior endoderm (aPVE)

Structure	Level	Pattern	Image	Note
TS12: hindgut diverticulum endoderm	Present	Regionally restricted	3F , 3H	Co-expression with Oct-3/4 (Pou5f1) in cells of allantois-associated posterior endoderm (aPVE)

Structure	Level	Pattern	Image	Note
TS12: hindgut diverticulum endoderm	Present	Regionally restricted	3L , 3J	Co-expression with Oct-3/4 (Pou5f1) in all expressing cells in ventral hindgut endoderm. Expression throughout nucleus, including perinucleus and core.

Structure	Level	Pattern	Image	Note
TS13: primitive hindgut	Present	Regionally restricted	3P , 3R	Expression in increased numbers of cells co-expressing with Oct-3/4 (Pou5f1) throughout hindgut lip. Co-expressing cells remain clustered within hindgut lip, not in any other visceral endoderm.

Structure	Level	Pattern	Image	Note
TS13: hindgut diverticulum endoderm	Present	Widespread	3T , 3V	Increased numbers of cells co-expressing with Oct-3/4 (Pou5f1) throughout ventral hindgut endoderm, spanning longitudinal extent of hindgut. Expression throughout nucleus, including perinucleus and core.

Structure	Level	Pattern	Image	Note
TS11: allantois mesoderm	Present	Single cells		Rare Allantoic Core Domain cells co-expressed Stella (Dppa3), Oct-3/4 (Pou5f1) and T, but only at the LHF stage.

Structure	Level	Pattern	Image	Note
TS12: foregut diverticulum	Absent			Co-expressing cells not observed within foregut.
TS12: posterior visceral endoderm	Present	Regionally restricted		Co-expressing cells not observed in posterior visceral endoderm anterior to the site of hindgut invagination, through the 12s stage.

Structure	Level	Pattern	Image	Note
TS10: allantois mesoderm	Present	Regionally restricted	4B , 4D	Expression in allantoic bud at extraembryonic primitive streak (XPS)

Structure	Level	Pattern	Image	Note
TS10: allantois mesoderm	Present		4F , 4H	Expression in allantoic bud at extraembryonic primitive streak (XPS). Some co-express T; many do not.

Structure	Level	Pattern	Image	Note
TS11: allantois mesoderm	Present	Regionally restricted	4J , 4L	Expression in Allantoic Core domain (ACD). Co-expression with T in some cells; no T expression in others.

Structure	Level	Pattern	Image	Note
TS11: posterior visceral endoderm	Present	Regionally restricted	4N , 4M	Expression in allantois-associated posterior visceral endoderm (aPVE) in cells distinct from Foxa2-expressing cells.

Structure	Level	Pattern	Image	Note
TS12: posterior visceral endoderm	Present	Regionally restricted	6E , 6G	Expression in allantois-associated posterior visceral endoderm (aPVE) in cells distinct from Foxa2-expressing cells.

Structure	Level	Pattern	Image	Note
TS12: primitive hindgut	Present	Regionally restricted	6K , 6I	Some expressing cells in visceral endoderm of hindgut lip (HGL) co-express Foxa2. Some expressing cells in nearby visceral endoderm exclude Foxa2 expression.

Structure	Level	Pattern	Image	Note
TS12: hindgut diverticulum	Present	Regionally restricted	6M , 6O	Expression in hindgut in cells were distinct from cells expressing Foxa2.

Structure	Level	Pattern	Image	Note
TS12: primitive hindgut	Ambiguous	Regionally restricted	7D , 7B	Expression in hindgut lip. No expression in cell at metaphase/anaphase.

Structure	Level	Pattern	Image	Note
TS12: primitive hindgut	Present	Regionally restricted	7I , 7G	Expression in hindgut lip. Expression in daughter cells at telophase with apparent symmetric expression in daughter cells.

Structure	Level	Pattern	Image	Note
TS12: primitive hindgut	Present	Regionally restricted	7N , 7L	Expression in hindgut lip. Expression in cell at anaphase with apparent symmetric expression in daughter cells.

Structure	Level	Pattern	Image	Note
TS12: primitive hindgut	Present	Regionally restricted	7Q , 7S	Expression in hindgut lip. Expression in cell at telophase with apparent asymmetric expression in one daughter cell.

Structure	Level	Pattern	Image	Note
TS13: hindgut diverticulum	Present	Regionally restricted	8I , 8G	Co-expression with Runx1 within hindgut endoderm, both nuclear and cytoplasmic profiles.

Structure	Level	Pattern	Image	Note
TS13: hindgut diverticulum	Present	Regionally restricted	8M , 8K	Co-expression with Runx1 within hindgut endoderm, both nuclear and cytoplasmic profiles.