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Display additional annotations [+]
Gene |
Clone |
Species |
Stages |
Anatomy |
tpm1
|
|
laevis
|
NF stage 24
|
notochord
,
somite
,
paraxial mesoderm
|
tpm1
|
|
laevis
|
NF stage 26
to
NF stage 28
|
myocardium
,
heart primordium
|
tpm1
|
|
laevis
|
NF stage 31
|
heart
,
myocardium
,
cardiovascular system
,
muscle
,
heart primordium
|
fbn2
|
|
laevis
|
NF stage 24
|
head mesoderm
,
notochord
,
presomitic mesoderm
,
prechordal plate
,
axial mesoderm
|
fbn2
|
|
laevis
|
NF stage 26
to
NF stage 28
|
cement gland primordium
,
myocardium
,
muscle
,
heart primordium
|
|
|
FIG. 3. Milestones of early cardiac development in Xenopus visualized by confocal images of double-immunostained embryos. Embryos selected to represent a chronology of stages were double labeled with anti-tropomyosin (CH1) (red) and anti-fibrillin (JB3) (green) and optically sectioned. For each stage, the set of optical sections (28 to 40 sections, 4 to 6 um thick) was digitally compiled in increments of 4 to 6 sections. Resulting optical thick sections that aid in the visualization of Xenopus heart development are presented. The order of presentation for stages with m ore than one image is ventral to dorsal. Image A is a parasagittal view of a stage 24 hemisectioned embryo. The stage 26 embryo in B is shown from the left lateral view. Images of stages 28 (C and D) and 31 (E) are ventral views of heart regions with the anterior of the em bryos placed at the top. At stage 24, the heart anlage is present but not immunohistochemically active. By stage 26, the first presence of antibody reactivity is noted near the ventral midline (ventral midline lies between arrowheads). At stage 28 (C and D), differentiation of the heart anlage is clear; the pericardial cavity can be discerned. Stage 31 (E)he heart region extends ventrally beyond the pericardial cavity and is slightly bent laterally to the embryo right; the myocardial wall does not yet close. Scale bars as denoted. |
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Display additional annotations [+]
Gene |
Clone |
Species |
Stages |
Anatomy |
tnnt2
|
|
laevis
|
NF stage 35 and 36
|
heart
,
myocardium
,
muscle
,
cardiac ventricle
|
tnnt2
|
|
laevis
|
NF stage 41
|
heart
,
myocardium
,
muscle
,
left atrium
,
right atrium
,
[+]
|
tnnt2
|
|
laevis
|
NF stage 44
|
heart
,
myocardium
,
muscle
,
left atrium
,
right atrium
,
[+]
|
fbn2
|
|
laevis
|
NF stage 41
|
heart
,
left atrium
,
right atrium
,
cardiac ventricle
|
|
|
FIG. 4. Milestones of early cardiac development in Xenopus (continued). Embryos were double labeled with anti-cardiac troponin T (CT3) (red) and anti-fibrillin (JB3) (green) and optically sectioned. For each stage, the set of optical sections (35 to 53 sections 5 to 7 um thick) was digitally compiled in increments of 6 to 9 sections. Resulting ventral views of optical thick sections are presented. By stage 35 (A and B) the myocardial wall is closed and the heart tube has become twisted in a S shape; the chambers are now distinct. Stage 41 (C and D) The myocardium thickens and develops trabeculae; the atrium is posterior to the ventricle. At stage 44 (E and F) the single atrium begins to be partitioned by the forming septum and is pushed slightly anterior to the ventricle. Scale bar, 100um. |