Cell proliferation and morphological patterns in the hydroids Tubularia and Hydractinia

Development ◽  
1967 ◽  
Vol 17 (3) ◽  
pp. 607-616
Author(s):  
Richard D. Campbell
Keyword(s):  
Cell Proliferation ◽  
Cell Division ◽  
Normal Growth ◽  
Tissue Growth ◽  
Body Form ◽  
Tissue Form ◽  
Morphological Patterns

Morphogenesis has been extensively studied in many hydroids, both during normal growth (Kühn, 1914; Berrill, 1961) and during regeneration (Tardent, 1963). Less is known about the patterns of cell proliferation underlying changes in tissue form. In several cases where cell division has been studied, surprisingly little direct correlation was found between areas of apparent morphological growth and patterns of cell proliferation (Overton, 1963; Crowell, Wyttenbach & Suddith, 1965; Shostak, Patel & Burnett, 1965; Wyttenbach, 1965; Campbell, 1967a, b). To explore further the relations between tissue growth and body form, I have examined histologically hydroids of two genera, Tubularia and Hydractinia, each of which has morphological pecularities. Tubularia possesses two whorls of tentacles and one whorl of gonophores, and thus has as many distinct hydranth regions as any hydroid. In the Hydractinia colony, four morphologically distinct polyp types are present.

scholarly journals Extracellular-Vesicle-Based Coatings Enhance Bioactivity of Titanium Implants—SurfEV

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1445
Author(s):  
Taisa Nogueira Pansani ◽  
Thanh Huyen Phan ◽  
Qingyu Lei ◽  
Alexey Kondyurin ◽  
Bill Kalionis ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Titanium Surface ◽  
Wound Closure ◽  
Cell Types ◽  
Extracellular Vesicle ◽  
Tissue Growth ◽  
Titanium Implants ◽  
The Body ◽  
High Concentrations ◽  
And Migration

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.

scholarly journals Cell fate clusters in ICM organoids arise from cell fate heredity and division: a modelling approach

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tim Liebisch ◽  
Armin Drusko ◽  
Biena Mathew ◽  
Ernst H. K. Stelzer ◽  
Sabine C. Fischer ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Division ◽  
Cell Fate ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Cell Lineage ◽  
Cell Fate Decision ◽  
Cell Fate Decisions ◽  
Chemical Signalling ◽  
Fate Decision

AbstractDuring the mammalian preimplantation phase, cells undergo two subsequent cell fate decisions. During the first decision, the trophectoderm and the inner cell mass are formed. Subsequently, the inner cell mass segregates into the epiblast and the primitive endoderm. Inner cell mass organoids represent an experimental model system, mimicking the second cell fate decision. It has been shown that cells of the same fate tend to cluster stronger than expected for random cell fate decisions. Three major processes are hypothesised to contribute to the cell fate arrangements: (1) chemical signalling; (2) cell sorting; and (3) cell proliferation. In order to quantify the influence of cell proliferation on the observed cell lineage type clustering, we developed an agent-based model accounting for mechanical cell–cell interaction, i.e. adhesion and repulsion, cell division, stochastic cell fate decision and cell fate heredity. The model supports the hypothesis that initial cell fate acquisition is a stochastically driven process, taking place in the early development of inner cell mass organoids. Further, we show that the observed neighbourhood structures can emerge solely due to cell fate heredity during cell division.

scholarly journals A possible relation between dietary zinc and cAMP in the regulation of tumour cell proliferation in the rat

1988 ◽  
Vol 59 (3) ◽  
pp. 437-442 ◽  
Author(s):  
Noel S. Skeef ◽  
John R. Duncan
Keyword(s):  
Cell Proliferation ◽  
Cell Division ◽  
Cell Line ◽  
Tumour Cell ◽  
Tumour Growth ◽  
Zn Deficiency ◽  
Regenerating Liver ◽  
Small Reduction ◽  
Dietary Zinc ◽  
Camp Concentration

1. The possibility of an effect of zinc on the rate of tumour cell division, mediated through a regulation of cellular cAMP concentration, was investigated in the present study in rats.2. Dietary Zn deficiency (< 1·5 mg Zn/kg) but not Zn excess (500 mg Zn/kg) resulted in an increased cAMP concentration in transplanted hepatoma cells. Neither treatment had any effect on the cAMP concentration in regenerating liver or normal resting liver. Both the deficient and excess Zn diets resulted in a small reduction in tumour growth (not statistically significant).3. The results seem to indicate that the relation investigated in the present study does not apply in the cell line used.

scholarly journals Role of Cell Division Autoantigen 1 (CDA1) in Cell Proliferation and Fibrosis

Genes ◽  
2010 ◽  
Vol 1 (3) ◽  
pp. 335-348 ◽  
Author(s):  
Ban-Hock Toh ◽  
Yugang Tu ◽  
Zemin Cao ◽  
Mark E. Cooper ◽  
Zhonglin Chai
Keyword(s):  
Cell Proliferation ◽  
Cell Division

scholarly journals INTERCELLULAR COMMUNICATION AND TISSUE GROWTH

1967 ◽  
Vol 33 (2) ◽  
pp. 235-242 ◽  
Author(s):  
Werner R. Loewenstein ◽  
Richard D. Penn
Keyword(s):  
Intercellular Communication ◽  
Wound Closure ◽  
Cell Movement ◽  
Normal Growth ◽  
Tissue Growth ◽  
Cellular Communication ◽  
Mechanical Contact ◽  
Cell Systems ◽  
Intact State ◽  
Striking Contrast

Intercellular communication was examined in regenerating rat liver and urodele skin, two tissues of fast but normal growth. In both, cellular communication is in general as good as in their respective normal intact state. This stands in striking contrast to the lack of cellular communication in tissues with cancerous growth. Upon wounding of the urodele skin, the normally permeable junctional membranes of cells near the wound border seal themselves off, thereby insulating the interiors of the communicated cell systems from the exterior. When the cells of two opposing borders make mechanical contact in the course of wound closure, communication between them ensues within 30 min. Within this period all cell movement also ceases ("contact inhibition"). The possible implications of these findings in the control of tissue growth are discussed.

scholarly journals Molecular mechanism of cytokinin-activated cell division in Arabidopsis

Science ◽  
2021 ◽  
Vol 371 (6536) ◽  
pp. 1350-1355
Author(s):  
Weibing Yang ◽  
Sandra Cortijo ◽  
Niklas Korsbo ◽  
Pawel Roszak ◽  
Katharina Schiessl ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Division ◽  
Histidine Kinase ◽  
Feedback Loop ◽  
Apical Meristem ◽  
Nuclear Accumulation ◽  
Cytokinin Signaling ◽  
Positive Feedback Loop ◽  
Nuclear Shuttling ◽  
Stimulate Cell Proliferation

Mitogens trigger cell division in animals. In plants, cytokinins, a group of phytohormones derived from adenine, stimulate cell proliferation. Cytokinin signaling is initiated by membrane-associated histidine kinase receptors and transduced through a phosphorelay system. We show that in the Arabidopsis shoot apical meristem (SAM), cytokinin regulates cell division by promoting nuclear shuttling of Myb-domain protein 3R4 (MYB3R4), a transcription factor that activates mitotic gene expression. Newly synthesized MYB3R4 protein resides predominantly in the cytoplasm. At the G2-to-M transition, rapid nuclear accumulation of MYB3R4—consistent with an associated transient peak in cytokinin concentration—feeds a positive feedback loop involving importins and initiates a transcriptional cascade that drives mitosis and cytokinesis. An engineered nuclear-restricted MYB3R4 mimics the cytokinin effects of enhanced cell proliferation and meristem growth.

scholarly journals Talin mechanosensitivity is modulated by a direct interaction with cyclin-dependent kinase-1

2021 ◽  
Author(s):  
Rosemarie E. Gough ◽  
Matthew C. Jones ◽  
Thomas Zacharchenko ◽  
Shimin Le ◽  
Miao Yu ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Adhesion ◽  
Cell Division ◽  
Mechanical Response ◽  
Direct Interaction ◽  
Cyclin Dependent Kinase ◽  
Cell Cycle Regulator ◽  
Direct Binding

AbstractTalin is a mechanosensitive component of adhesion complexes that directly couples integrins to the actin cytoskeleton. In response to force, talin undergoes switch-like behaviour of its multiple rod domains that modulate interactions with its binding partners. Cyclin-dependent kinase-1 (CDK1) is a key regulator of the cell cycle, exerting its effects through synchronised phosphorylation of a large number of protein targets. CDK1 activity also maintains adhesion during interphase, and its inhibition is a prerequisite for the tightly choreographed changes in cell shape and adhesiveness that are required for successful completion of mitosis. Using a combination of biochemical, structural and cell biological approaches, we demonstrate a direct interaction between talin and CDK1 that occurs at sites of integrin-mediated adhesion. Mutagenesis demonstrated that CDK1 contains a functional talin-binding LD motif, and the binding site within talin was pinpointed to helical bundle R8 through the use of recombinant fragments. Talin also contains a consensus CDK1 phosphorylation motif centred on S1589; a site that was phosphorylated by CDK1in vitro. A phosphomimetic mutant of this site within talin lowered the binding affinity of KANK and weakened the mechanical response of the region, potentially altering downstream mechanotransduction pathways. The direct binding of the master cell cycle regulator, CDK1, to the primary integrin effector, talin, therefore provides a primordial solution for coupling the cell proliferation and cell adhesion machineries, and thereby enables microenvironmental control of cell division in multicellular organisms.SummaryThe direct binding of the master cell cycle regulator, CDK1, to the primary integrin effector, talin, provides a primordial solution for coupling the cell proliferation and cell adhesion machineries, and thereby enables microenvironmental control of cell division.

Expression of engrailed during segmentation in grasshopper and crayfish

Development ◽  
1989 ◽  
Vol 107 (2) ◽  
pp. 201-212 ◽  
Author(s):  
N.H. Patel ◽  
T.B. Kornberg ◽  
C.S. Goodman
Keyword(s):  
Monoclonal Antibody ◽  
Cell Proliferation ◽  
Cell Division ◽  
Embryonic Stage ◽  
Germ Band ◽  
Segmentation Genes ◽  
Pair Rule ◽  
Drosophila Embryos ◽  
The Way

We have used a monoclonal antibody that recognizes engrailed proteins to compare the process of segmentation in grasshopper, crayfish, and Drosophila. Drosophila embryos rapidly generate metameres during an embryonic stage characterized by the absence of cell division. In contrast, many other arthropod embryos, such as those of more primitive insects and crustaceans, generate metameres gradually and sequentially, as cell proliferation causes caudal elongation. In all three organisms, the pattern of engrailed expression at the segmented germ band stage is similar, and the parasegments are the first metameres to form. Nevertheless, the way in which the engrailed pattern is generated differs and reflects the differences in how these organisms generate their metameres. These differences call into question what role homologues of the Drosophila pair-rule segmentation genes might play in other arthropods that generate metameres sequentially.

Reduction of the rate of outgrowth, cell density, and cell division following removal of the apical ectodermal ridge of the chick limb-bud

Development ◽  
1977 ◽  
Vol 40 (1) ◽  
pp. 1-21
Author(s):  
Dennis Summerbell
Keyword(s):  
Cell Proliferation ◽  
Cell Death ◽  
Cell Division ◽  
Cell Density ◽  
Apical Ectodermal Ridge ◽  
Limb Bud ◽  
Short Term ◽  
Density Dependent ◽  
Wing Bud

Removal of the apical ectodermal ridge causes a reduction in the rate of outgrowth of the wing-bud and the loss of distal parts. More specifically it causes a short-term increase in cell density and cell death and a decrease in the rate of cell proliferation. The evidence supports the hypothesis of density-dependent control of cell division and suggests that there may also be a mechanism regulating skeletal length at the time of differentiation. An informal model is presented to explain the observations.

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