|
Gene |
Clone |
Species |
Stages |
Anatomy |
myod1.S
|
|
laevis
|
NF stage 26
|
somite
,
paraxial mesoderm
,
trunk somite
,
trunk
|
myod1.S
|
|
laevis
|
NF stage 28
to
NF stage 29 and 30
|
mesoderm
,
somite
,
paraxial mesoderm
,
trunk somite
|
myod1.S
|
|
laevis
|
NF stage 31
|
somite
,
muscle
,
otic placode
,
lens placode
,
epibranchial placode
,
[+]
|
myod1.S
|
|
laevis
|
NF stage 41
|
somite
,
muscle
,
ventral
,
head
,
hypaxial muscle
|
Display additional annotations [+]
Gene |
Clone |
Species |
Stages |
Anatomy |
pax3
|
|
laevis
|
NF stage 26
|
dorso-lateral
,
trunk somite
,
trigeminal ganglion
|
pax3
|
|
laevis
|
NF stage 28
|
brain
,
notochord
,
somite
,
trunk somite
,
trigeminal ganglion
,
[+]
|
pax3
|
|
laevis
|
NF stage 31
|
brain
,
notochord
,
somite
,
trunk somite
,
trigeminal ganglion
,
[+]
|
pax3
|
|
laevis
|
NF stage 37 and 38
to
NF stage 41
|
brain
,
notochord
,
somite
,
muscle
,
trunk somite
,
[+]
|
myf5
|
|
laevis
|
NF stage 26
to
NF stage 29 and 30
|
somite
,
ventro-lateral
,
trunk
|
myf5
|
|
laevis
|
NF stage 31
|
muscle
,
ventral
,
trunk somite
,
heart primordium
,
trunk
,
[+]
|
myf5
|
|
laevis
|
NF stage 37 and 38
|
somite
,
paraxial mesoderm
,
ventral
,
heart primordium
,
musculature of face
,
[+]
|
myf5
|
|
laevis
|
NF stage 41
|
musculature of face
,
trunk
,
hypaxial muscle
|
|
|
FIG. 2. Expression patterns of the myogenic transcription factors pax3, myf-5, and myoD. Upregulation of pax3 in the dorso-lateral lip of
the anterior trunk somites is apparent at stage 26 (A, arrows). By stage 28/29 pax3-positive cells can be seen leaving the somites and
migrating ventrally (B, arrows). At stage 37/38, pax3 cells can be seen at the front of the migration (D) as they continue to stream out of
the somites (D, arrow head). Stage-41 embryos have faint pax3 expression at the front of the migrating cells (E, arrows). Early myf-5
expression is restricted to the dorso-medial and ventro-lateral lips of the somites, marking the expanding epaxial myotome (F, G). At stage
31 (H, arrows), myf-5-expressing cells can clearly be seen outside of the somitic region migrating ventrally, and continuing to do so through
stages 37/38 (I) and 41 (J, arrows). Expression of myoD is present only in the somitic region (K) until stage 37/38 (N), when it appears
in discrete patches clearly separate from the somites (arrows). By stage 41, there are long stripes of myoD expression corresponding to the
differentiated ventral body wall muscle (O). Expression is greatest in the ventral-most region of the body wall, where skeletal muscle has
most recently differentiated. |
|
Display additional annotations [+]
|
|
FIG. 3. Embryos stained for either pax3 (A) or myoD (E) followed by 12/101 staining. Stage-37 embryos stained for pax3 expression
(A, B) reveal the pax3-expressing cells are just ventral to differentiated muscle (arrow heads), with little overlap, as indicated from a
transverse section (B) of embryo in (A) (arrow). The lack of overlap is more dramatic in stage-41 embryos (C, arrow). (D) A transverse section
of embryo in (C). The arrow shows pax3 expression which does not overlap with 12/101 staining (arrow heads). Stage-37 embryos stained
formyoD (E, F) indicate significant overlap ofmyoD expression and differentiatedmuscle (arrow heads in E, arrow in F). At stage 41, overlap
of myoD expression continues over a broad range of differentiated muscle (G), which can also be seen in (H) (arrows). In (B), (D), (F), and (H),
dorsal is toward the top of the page. |