scholarly journals Axial polarization cues impinge on early mesoderm patterning and specify vertebrate head mesoderm

2017 ◽  
Vol 145 ◽  
pp. S19
Author(s):  
Nitya Nandkishore ◽  
Bhakti Vyas ◽  
Alok Javali ◽  
Ramkumar Sambasivan
Keyword(s):  
Head Mesoderm ◽  
Axial Polarization ◽  
Mesoderm Patterning

scholarly journals Dynamic control of head mesoderm patterning

Development ◽  
2011 ◽  
Vol 138 (13) ◽  
pp. 2807-2821 ◽  
Author(s):  
I. Bothe ◽  
G. Tenin ◽  
A. Oseni ◽  
S. Dietrich
Keyword(s):  
Dynamic Control ◽  
Head Mesoderm ◽  
Mesoderm Patterning

Onset of the segmentation clock in the chick embryo: evidence for oscillations in the somite precursors in the primitive streak

Development ◽  
2002 ◽  
Vol 129 (5) ◽  
pp. 1107-1117 ◽  
Author(s):  
Caroline Jouve ◽  
Tadahiro Iimura ◽  
Olivier Pourquie
Keyword(s):  
Continuous Process ◽  
Notch Pathway ◽  
Primitive Streak ◽  
The Body ◽  
Paraxial Mesoderm ◽  
Segmentation Clock ◽  
Head Mesoderm ◽  
Dynamic Expression ◽  
Mesoderm Formation ◽  
Cyclic Gene

Vertebrate somitogenesis is associated with a molecular oscillator, the segmentation clock, which is defined by the periodic expression of genes related to the Notch pathway such as hairy1 and hairy2 or lunatic fringe (referred to as the cyclic genes) in the presomitic mesoderm (PSM). Whereas earlier studies describing the periodic expression of these genes have essentially focussed on later stages of somitogenesis, we have analysed the onset of the dynamic expression of these genes during chick gastrulation until formation of the first somite. We observed that the onset of the dynamic expression of the cyclic genes in chick correlated with ingression of the paraxial mesoderm territory from the epiblast into the primitive streak. Production of the paraxial mesoderm from the primitive streak is a continuous process starting with head mesoderm formation, while the streak is still extending rostrally, followed by somitic mesoderm production when the streak begins its regression. We show that head mesoderm formation is associated with only two pulses of cyclic gene expression. Because such pulses are associated with segment production at the body level, it suggests the existence of, at most, two segments in the head mesoderm. This is in marked contrast to classical models of head segmentation that propose the existence of more than five segments. Furthermore, oscillations of the cyclic genes are seen in the rostral primitive streak, which contains stem cells from which the entire paraxial mesoderm originates. This indicates that the number of oscillations experienced by somitic cells is correlated with their position along the AP axis.

scholarly journals Charting cell migration dynamics during lateral plate mesoderm patterning in zebrafish using lightsheet microscopy

2017 ◽  
Vol 145 ◽  
pp. S79-S80
Author(s):  
Karin Dorien Prummel ◽  
Christopher Hess ◽  
Eline Brombacher ◽  
Anastasia Felker ◽  
Christian Mosimann
Keyword(s):  
Cell Migration ◽  
Lateral Plate Mesoderm ◽  
Lateral Plate ◽  
Migration Dynamics ◽  
Mesoderm Patterning

Analysis of the Determination of the Olfactory Placode in Amblystoma punctatum

Development ◽  
1956 ◽  
Vol 4 (2) ◽  
pp. 120-138
Author(s):  
Alex J. Haggis
Keyword(s):  
Thin Layer ◽  
Self Determination ◽  
Olfactory Organ ◽  
Preliminary Stage ◽  
Olfactory Placode ◽  
Head Mesoderm ◽  
Olfactory Organs

The analysis of the factors involved in the determination of the olfactory organ or ‘nose’ in amphibians is still in a preliminary stage. Obviously, like all other ectodermal structures, this organ owes its emergence to inductive stimuli derived from adjacent tissues. In the numerous isolation experiments performed on the gastrula ectoderm of different species olfactory organs never occurred. The earliest stage at which the prospective nose ectoderm was found to be capable of self-determination was the early neurula (Carpenter, 1937; Zwilling, 1940). The question arose as to which of the tissues in the immediate environment of the nose represents its inductor. The tip of the forebrain primordium and/or the thin layer of rostral head mesoderm seemed to be worth serious consideration. Evidence in favour of the view that the head mesoderm is directly engaged in nose induction is rather slim and inconclusive.

Expression of an engrailed-related protein is induced in the anterior neural ectoderm of early Xenopus embryos

Development ◽  
1989 ◽  
Vol 106 (3) ◽  
pp. 611-617 ◽  
Author(s):  
A.H. Brivanlou ◽  
R.M. Harland
Keyword(s):  
Nuclear Protein ◽  
Neural Plate ◽  
Brain Cells ◽  
Related Protein ◽  
Anterior Portion ◽  
Head Mesoderm ◽  
C Terminus ◽  
Licl Treatment ◽  
Neural Ectoderm ◽  
Xenopus Laevis Embryos

We have used a monoclonal antibody directed against the C-terminus of the Drosophila invected homeodomain to detect a nuclear protein in brain cells of Xenopus laevis embryos. We refer to this antigen as the Xenopus EN protein. The EN protein is localized at midneurula stage to a band of cells in the anterior portion of the neural plate, on each side of the neural groove. Later in development, the expression coincides with the boundary of the midbrain and hindbrain, and persists at least to the swimming tadpole stage. These properties make the EN protein an excellent molecular marker for anterior neural structures. In embryos where inductive interactions between mesodermal and ectodermal tissues have been perturbed, the expression of the EN protein is altered; in embryos that have been anterodorsalized by LiCl treatment, the region that expresses the EN protein is expanded, but still well organized. In ventralized UV-irradiated embryos, the absence of the protein is correlated with the absence of anterior neural structures. In extreme exogastrulae, where the contacts between head mesoderm and prospective neurectoderm are lost, the EN protein is not expressed.

Sign in / Sign up

Export Citation Format

Share Document