scholarly journals In vivo embryonic expression of laminin and its involvement in cell shape change in the sea urchin Sphaerechinus granularis

Development ◽  
1987 ◽  
Vol 101 (4) ◽  
pp. 659-671 ◽  
Author(s):  
R.A. McCarthy ◽  
M.M. Burger
Keyword(s):  
Monoclonal Antibody ◽  
Sea Urchin ◽  
Basal Lamina ◽  
Cell Shape ◽  
Shape Change ◽  
Cell Shape Change ◽  
A Cell ◽  
Mesenchyme Cells ◽  
Embryonic Epithelium

Laminin, a component of the embryonic sea urchin basal lamina, is recognized by monoclonal antibody BL1 (Mab BL1). Our results demonstrate that laminin is secreted into the blastcoel at the early blastula stage at a time when the blastomeres undergo a cell shape change and are organized into an epithelium. Laminin is present on the basal surfaces of ectodermal cells and is absent or reduced on migrating primary mesenchyme cells. Microinjection of a monoclonal antibody directed against laminin induces a morphological change in cell shape and a deformation of the embryonic epithelium. Investigation of selected stages of live embryos suggests that the distribution of laminin may be heterogeneous within the basal lamina during early development. The results implicate laminin as a mediator of cell shape change during early morphogenesis.

scholarly journals Apical Accumulation of Rho in the Neural Plate Is Important for Neural Plate Cell Shape Change and Neural Tube Formation

2008 ◽  
Vol 19 (5) ◽  
pp. 2289-2299 ◽  
Author(s):  
Nagatoki Kinoshita ◽  
Noriaki Sasai ◽  
Kazuyo Misaki ◽  
Shigenobu Yonemura
Keyword(s):  
Neural Tube ◽  
Rho Gtpases ◽  
Cell Shape ◽  
Shape Change ◽  
Myosin Ii ◽  
Tube Formation ◽  
Neural Plate ◽  
Cell Shape Change ◽  
Neural Tube Formation

Although Rho-GTPases are well-known regulators of cytoskeletal reorganization, their in vivo distribution and physiological functions have remained elusive. In this study, we found marked apical accumulation of Rho in developing chick embryos undergoing folding of the neural plate during neural tube formation, with similar accumulation of activated myosin II. The timing of accumulation and biochemical activation of both Rho and myosin II was coincident with the dynamics of neural tube formation. Inhibition of Rho disrupted its apical accumulation and led to defects in neural tube formation, with abnormal morphology of the neural plate. Continuous activation of Rho also altered neural tube formation. These results indicate that correct spatiotemporal regulation of Rho is essential for neural tube morphogenesis. Furthermore, we found that a key morphogenetic signaling pathway, the Wnt/PCP pathway, was implicated in the apical accumulation of Rho and regulation of cell shape in the neural plate, suggesting that this signal may be the spatiotemporal regulator of Rho in neural tube formation.

scholarly journals Triggering a Cell Shape Change by Exploiting Preexisting Actomyosin Contractions

Science ◽  
2012 ◽  
Vol 335 (6073) ◽  
pp. 1232-1235 ◽  
Author(s):  
Minna Roh-Johnson ◽  
Gidi Shemer ◽  
Christopher D. Higgins ◽  
Joseph H. McClellan ◽  
Adam D. Werts ◽  
...  
Keyword(s):  
Cell Shape ◽  
Shape Change ◽  
Cell Shape Change ◽  
A Cell

scholarly journals Dynamic myosin phosphorylation regulates contractile pulses and tissue integrity during epithelial morphogenesis

2014 ◽  
Vol 206 (3) ◽  
pp. 435-450 ◽  
Author(s):  
Claudia G. Vasquez ◽  
Mike Tworoger ◽  
Adam C. Martin
Keyword(s):  
Cell Shape ◽  
Shape Change ◽  
Epithelial Morphogenesis ◽  
Nonmuscle Myosin ◽  
Apical Constriction ◽  
Tissue Integrity ◽  
Cell Shape Change ◽  
Nonmuscle Myosin Ii ◽  
A Cell ◽  
Coupling Dynamic

Apical constriction is a cell shape change that promotes epithelial bending. Activation of nonmuscle myosin II (Myo-II) by kinases such as Rho-associated kinase (Rok) is important to generate contractile force during apical constriction. Cycles of Myo-II assembly and disassembly, or pulses, are associated with apical constriction during Drosophila melanogaster gastrulation. It is not understood whether Myo-II phosphoregulation organizes contractile pulses or whether pulses are important for tissue morphogenesis. Here, we show that Myo-II pulses are associated with pulses of apical Rok. Mutants that mimic Myo-II light chain phosphorylation or depletion of myosin phosphatase inhibit Myo-II contractile pulses, disrupting both actomyosin coalescence into apical foci and cycles of Myo-II assembly/disassembly. Thus, coupling dynamic Myo-II phosphorylation to upstream signals organizes contractile Myo-II pulses in both space and time. Mutants that mimic Myo-II phosphorylation undergo continuous, rather than incremental, apical constriction. These mutants fail to maintain intercellular actomyosin network connections during tissue invagination, suggesting that Myo-II pulses are required for tissue integrity during morphogenesis.

scholarly journals Apical constriction: A cell shape change that can drive morphogenesis

2010 ◽  
Vol 341 (1) ◽  
pp. 5-19 ◽  
Author(s):  
Jacob M. Sawyer ◽  
Jessica R. Harrell ◽  
Gidi Shemer ◽  
Jessica Sullivan-Brown ◽  
Minna Roh-Johnson ◽  
...  
Keyword(s):  
Cell Shape ◽  
Shape Change ◽  
Apical Constriction ◽  
Cell Shape Change ◽  
A Cell

Delamination and tyrosine phosphorylation of SUp62 during early embryogenesis of sea urchin

Zygote ◽  
1999 ◽  
Vol 8 (S1) ◽  
pp. S39-S40
Author(s):  
Hideki Katow
Keyword(s):  
Tyrosine Phosphorylation ◽  
Sea Urchin ◽  
Basal Lamina ◽  
Surface Protein ◽  
Adhesion Protein ◽  
Guidance Cue ◽  
Sea Urchin Embryo ◽  
A Cell ◽  
Mesenchyme Cells ◽  
Migratory Cells

The ingression of primary mesenchyme cells (PMCs) in the sea urchin embryo is initiated with local degradation of the basal lamina at the vegetal plate epithelium (e.g. Katow & Solursh, 1980). The ingressed PMCs encounter pamlin, a cell adhesion protein in the basal lamina (Katow, 1995), which guides PMC migration to a particular embryonic region to form a ring pattern (Katow & Komazaki, 1996; Katow et al, 2000). Thus extracellular matrix (ECM) provides a necessary guidance cue to the migratory cells, and this implicates the occurrence of intracellular signalling to promote not only cell locomotion but also orientation for the migration. Using embryos of the sea urchin, Hemicentrotus pulcherrimus, I report the temporal expression of P35, a PMC surface protein, during the very early stages of PMC ingression that is downregulated with SUp62 protein in the cytoplasm, and tyrosine phosphorylation of SUp62 as a consequence of PMCs encountering pamlin in light of ECM/cell signal transduction.

Sign in / Sign up

Export Citation Format

Share Document