Probe:	Fgf-5 cDNA1
Probe preparation:	Antisense labelled with S35 RNA
Visualized with:	Autoradiography

Structure	Level	Pattern	Image	Note
TS7: embryo	Absent		1B/C	Authors state that "in one of the embryos removed from the uterus during this period" (i.e. one less advanced in development), Fgf5 mRNA was not detectable.

Structure	Level	Pattern	Image	Note
TS8: epiblast	Strong	Uniform	1E/F	Fgf5 mRNA was readily detectable at uniformly high levels throughout the embryonic ectoderm at this stage.
TS8: extraembryonic component	Present	Regionally restricted	1E/F	Fgf5 mRNA was undetectable in the proximal extraembryonic tissue.
TS8: extraembryonic visceral endoderm	Ambiguous		1E/F	Authors state that it was difficult to determine whether Fgf5 mRNA was expressed in visceral endoderm cells.

Structure	Level	Pattern	Image	Note
TS10: embryo	Present	Regionally restricted	2C/D	Expression of Fgf5 remained restricted to the embryonic portion of the conceptus.
TS10: embryo ectoderm	Strong	Graded	2C/D	Levels of Fgf5 mRNA appeared to be relatively high throughout the embryonic ectoderm, with evidence of differential expression along the proximodistal axis; the signal intensity in the most proximal region was lower than in the most distal region.
TS10: embryo endoderm	Strong	Regionally restricted	2C/D	Observed both Fgf5-expressing (likely definitive endoderm cells) and non-expressing cells in the endodermal cell layer. Distally, Fgf5 mRNA was detected a levels similar to those in adjacent embryonic ectoderm; proximally, no Fgf5 mRNA was detectable
TS10: embryo mesoderm	Strong	Regionally restricted	2C/D	Fgf5 was not detected in cells that had migrated either proximally into the extraembryonic region or proximolaterally between embryonic ectoderm and visceral endoderm. Cells exiting the streak more distally expressed Fgf5 similarly to distal ectoderm.
TS10: primitive streak	Strong	Regionally restricted	2C/D	Fgf5 mRNA levels were relatively high throughout the streak, with differential expression along the proximodistal axis; signal intensity in the most proximal region was 2- to 3-fold lower than in the most distal region.
TS10: extraembryonic component	Absent		2C/D	Fgf5 expression remained restricted to the embryonic portion of the conceptus.

Structure	Level	Pattern	Image	Note
TS11: embryo ectoderm	Strong	Graded	3B/C	Embryonic ectoderm expressed Fgf5 mRNA, with increasingly higher levels detectable towards the distal end.
TS11: embryo endoderm	Strong		3B/C	The endoderm surrounding the embryo, a mixed population of epiblast-derived and primitive endoderm-derived cells, contains levels of Fgf5 mRNA similar to those in adjacent mesoderm.
TS11: embryo mesoderm	Strong	Regionally restricted	3B/C	No expression was detected in proximolateral mesoderm, whereas distal mesoderm was positive (roughly the same levels as in adjacent ectoderm). Head process cells 9cells that have migrated anterior to the distal end of the streak) were also positive.
TS11: allantois mesoderm	Absent		3B/C	No Fgf5 expression was detected in extraembryonic mesoderm.
TS11: amnion mesoderm	Absent		3B/C	No Fgf5 expression was detected in extraembryonic mesoderm.
TS11: chorion mesoderm	Absent		3B/C	No Fgf5 expression was detected in extraembryonic mesoderm.
TS11: yolk sac mesoderm	Absent		3B/C	No Fgf5 expression was detected in extraembryonic mesoderm.

Structure	Level	Pattern	Image	Note
TS11: embryo	Absent		3D/E	Fgf5 mRNA was not detected in embryos at this stage (E7.75), as determined by serial section analysis through the embryo, although it was abundant in embryos from the same litter that were not as advanced in development

Structure	Level	Pattern	Image	Note
TS8: epiblast	Strong	Uniform		Expression was readily detectable at uniformly high levels throughout the embryonic ectoderm at this stage.

Structure	Level	Pattern	Image	Note
TS12: embryo	Absent