共查询到20条相似文献,搜索用时 15 毫秒
1.
Background
Tight junctions are required for epithelial barrier formation and participate in the regulation of signalling mechanisms that control proliferation and differentiation. ZO-1 is a tight junction-associated adaptor protein that regulates gene expression, junction assembly and epithelial morphogenesis. We have previously demonstrated that the heat shock protein Apg-2 binds ZO-1 and thereby regulates its role in cell proliferation. Here, we addressed the question whether Apg-2 is also important for junction formation and epithelial morphogenesis. 相似文献2.
Background
The Rho-kinases (ROCKs) are major effector targets of the activated Rho GTPase that have been implicated in many of the Rho-mediated effects on cell shape and movement via their ability to affect acto-myosin contractility. The role of ROCKs in cell shape change and motility suggests a potentially important role for Rho-ROCK signaling in tissue morphogenesis during development. Indeed, in Drosophila, a single ROCK ortholog, DRok, has been identified and has been found to be required for establishing planar cell polarity. 相似文献3.
Tina Jaskoll Haiming Chen Yan Min Zhou Dingwen Wu Michael Melnick 《BMC developmental biology》2001,1(1):5-6
Background
The regulation of programmed cell death is critical to developmental homeostasis and normal morphogenesis of embryonic tissues. Survivin, a member of the inhibitors of apoptosis protein (IAP) family primarily expressed in embryonic cells, is both an anti-apoptosis and a pro-survival factor. Since our previous studies have demonstrated the importance of apoptosis during embryonic submandibular salivary gland (SMG) development, we postulated that survivin is a likely mediator of SMG epithelial cell survival. 相似文献4.
Thomas Williamson Jean-Marc Schwartz Douglas B Kell Lubomira Stateva 《BMC systems biology》2009,3(1):70
Background
Cyclic adenosine monophosphate (cAMP) has a key signaling role in all eukaryotic organisms. In Saccharomyces cerevisiae, it is the second messenger in the Ras/PKA pathway which regulates nutrient sensing, stress responses, growth, cell cycle progression, morphogenesis, and cell wall biosynthesis. A stochastic model of the pathway has been reported. 相似文献5.
6.
Tasha S Smith Jaimie M Pineda Alex C Donaghy Cynthia K Damer 《BMC developmental biology》2010,10(1):59
Background
Copines are calcium-dependent phospholipid-binding proteins found in diverse eukaryotic organisms. We are studying the function of copines in Dictyostelium discoideum, a single-celled amoeba that undergoes cell differentiation and morphogenesis to form multicellular fruiting bodies when placed in starvation conditions. Previously, we showed that Dictyostelium cells lacking the copine A (cpnA) gene are not able to complete the developmental cycle, arresting at the slug stage. The aim of this study is to further characterize the developmental defect of the cpnA- cells. 相似文献7.
Background
A key event in plant morphogenesis is the establishment of a division plane. A plant-specific microtubular preprophase band (PPB) accurately predicts the line of cell division, whereas the phragmoplast, another plant-specific array, executes cell division by maintaining this predicted line. Although establishment of these specific arrays apparently involves intracellular repolarization events that focus cellular resources to a division site, it still remains unclear how microtubules position the cell division planes. Here we study GFP-AtEB1 decorated microtubule plus-ends to dissect events at the division plane. 相似文献8.
This study continues our previous experiments intended to elucidate the role of sucrose in a figured wood formation in silver birch (Betula pendula Roth var. carelica). The purpose of the study was the investigation of the role of sucrose in the regulation of cell division in the cambial zone. Using an earlier-developed technique, sucrose solutions of different concentrations have been delivered into trunk tissues of silver birch. A microscopic analysis of samples collected 28 days after the beginning of the experiment has shown that an increased sucrose concentration in an exogenous solution causes an increase in the frequency of anticlinal cell divisions in the cambial zone. In the case of high sucrose concentrations (10 or 20%), the zone of anticlinal divisions is significantly wider than in variants with low sucrose concentrations, since anticlinal divisions are observed on both phloem and xylem sides and at a larger distance from rays. A comparison of the obtained results with the previous experiments shows that the increased frequency of anticlinal divisions in cambial cells observed in the case of application of 10 or 20% sucrose solutions coincides with an increased parenchymatization of tissues. A revealed localization of anticlinal divisions within the cambial zone indicates that, in the case of the exogenous sucrose uptake, the morphogenesis of conductive tissues in silver birch (Betula pendula Roth var. pendula) occurs in the same way as in Karelian birch (Betula pendula Roth var. carelica). Data presented in this paper agree with the earlier hypothesis that the formation of figured wood similar to that of Karelian birch occurs due to increased sucrose content in trunk tissues. 相似文献
9.
Heena Panchal Olivia Wansbury Suzanne Parry Alan Ashworth Beatrice Howard 《BMC developmental biology》2007,7(1):105
Background
The Neuregulin family of ligands and their receptors, the Erbb tyrosine kinases, have important roles in epidermal and mammary gland development as well as during carcinogenesis. Previously, we demonstrated that Neuregulin3 (Nrg3) is a specification signal for mammary placode formation in mice. Nrg3 is a growth factor, which binds and activates Erbb4, a receptor tyrosine kinase that regulates cell proliferation and differentiation. To understand the role of Neuregulin3 in epidermal morphogenesis, we have developed a transgenic mouse model that expresses Nrg3 throughout the basal layer (progenitor/stem cell compartment) of mouse epidermis and the outer root sheath of developing hair follicles. 相似文献10.
Young Chul Kim Rod J Clark Francisco Pelegri Caroline M Alexander 《BMC developmental biology》2009,9(1):55-12
Background
Brisken et al (2000) showed that Wnt4 null mammary glands were deficient in early lobuloalveolar mammary outgrowth during pregnancy, and implicated Wnt4 as an effector for the progesterone-induced mammary growth program. Though ectopic Wnt1 signaling is known to be mitogenic and oncogenic, no endogenously expressed Wnt ligands have ever been directly implicated in mammary growth and morphogenesis. Therefore, we generated conditional transgenic mice to test whether Wnt4 can stimulate mammary epithelial cell growth. 相似文献11.
12.
Background
Involvement of conservative molecular modules and cellular mechanisms in the widely diversified processes of eukaryotic cell morphogenesis leads to the intriguing question: how do similar proteins contribute to dissimilar morphogenetic outputs. Formins (FH2 proteins) play a central part in the control of actin organization and dynamics, providing a good example of evolutionarily versatile use of a conserved protein domain in the context of a variety of lineage-specific structural and signalling interactions. 相似文献13.
Chloroplasts change their intracellular positions in response to their light environment. Under darkness, chloroplasts assume
special positions that are different from those under light conditions. Here, we analyzed chloroplast dark positioning using
Adiantum capillus-veneris gametophyte cells. When chloroplasts were transferred into darkness, during the first 1–5 h, they moved towards the anticlinal
cell walls bordering the adjacent cells rather rapidly. Then, they slowed down and accumulated at the anticlinal walls gradually
over the following 24–36 h. The chloroplast movements could be roughly classified into two different categories: initial rapid
straight movement and later, slow staggering movement. When the chloroplast accumulation response was induced in dark-adapted
cells by partial cell irradiation with a microbeam targeted to the center of the cells, chloroplasts moved towards the beam
spot from the anticlinal walls. However, when the microbeam was switched off, they moved to the nearest anticlinal walls and
not to their original positions if they were not the closest, indicating that they know the direction of the nearest anticlinal
wall and do not have particular areas that they migrate to during dark positioning. 相似文献
14.
Jaime Millán Robert J Cain Natalia Reglero-Real Carolina Bigarella Beatriz Marcos-Ramiro Laura Fernández-Martín Isabel Correas Anne J Ridley 《BMC biology》2010,8(1):11
Background
Endothelial cell-cell junctions maintain endothelial integrity and regulate vascular morphogenesis and homeostasis. Cell-cell junctions are usually depicted with a linear morphology along the boundaries between adjacent cells and in contact with cortical F-actin. However, in the endothelium, cell-cell junctions are highly dynamic and morphologically heterogeneous. 相似文献15.
Juuti-Uusitalo K Klunder LJ Sjollema KA Mackovicova K Ohgaki R Hoekstra D Dekker J van Ijzendoorn SC 《PloS one》2011,6(8):e22967
Background
The cytokines TNF (TNFSF2) and IFNγ are important mediators of inflammatory bowel diseases and contribute to enhanced intestinal epithelial permeability by stimulating apoptosis and/or disrupting tight junctions. Apoptosis and tight junctions are also important for epithelial tissue morphogenesis, but the effect of TNF and IFNγ on the process of intestinal epithelial morphogenesis is unknown.Methods/Principal Findings
We have employed a three-dimensional cell culture system, reproducing in vivo-like multicellular organization of intestinal epithelial cells, to study the effect of TNF on intestinal epithelial morphogenesis and permeability. We show that human intestinal epithelial cells in three-dimensional culture assembled into luminal spheres consisting of a single layer of cells with structural, internal, and planar cell polarity. Exposure of preformed luminal spheres to TNF or IFNγ enhanced paracellular permeability, but via distinctive mechanisms. Thus, while both TNF and IFNγ, albeit in a distinguishable manner, induced the displacement of selected tight junction proteins, only TNF increased paracellular permeability via caspase-driven apoptosis and cell shedding. Infliximab and adalumimab inhibited these effects of TNF. Moreover, we demonstrate that TNF via its stimulatory effect on apoptosis fundamentally alters the process of intestinal epithelial morphogenesis, which contributes to the de novo generation of intestinal epithelial monolayers with increased permeability. Also IFNγ contributes to the de novo formation of monolayers with increased permeability, but in a manner that does not involve apoptosis.Conclusions
Our study provides an optimized 3D model system for the integrated analysis of (real-time) intestinal epithelial paracellular permeability and morphogenesis, and reveals apoptosis as a pivotal mechanism underlying the enhanced permeability and altered morphogenesis in response to TNF, but not IFNγ. 相似文献16.
Background
The polarization of somite-derived sclerotomes into anterior and posterior halves underlies vertebral morphogenesis and spinal nerve segmentation. To characterize the full extent of molecular differences that underlie this polarity, we have undertaken a systematic comparison of gene expression between the two sclerotome halves in the mouse embryo. 相似文献17.
Background
Interaction with the surrounding mesenchyme is necessary for development of endodermal organs, and Fibroblast growth factors have recently emerged as mesenchymal-expressed morphogens that direct endodermal morphogenesis. The fibroblast growth factor 10 (Fgf10) null mouse is characterized by the absence of lung bud development. Previous studies have shown that this requirement for Fgf10 is due in part to its role as a chemotactic factor during branching morphogenesis. In other endodermal organs Fgf10 also plays a role in regulating differentiation. 相似文献18.
Background
Cell polarity genes including Crumbs (Crb) and Par complexes are essential for controlling photoreceptor morphogenesis. Among the Crb and Par complexes, Bazooka (Baz, Par-3 homolog) acts as a nodal component for other cell polarity proteins. Therefore, finding other genes interacting with Baz will help us to understand the cell polarity genes'' role in photoreceptor morphogenesis.Methodology/Principal Findings
Here, we have found a genetic interaction between baz and centrosomin (cnn). Cnn is a core protein for centrosome which is a major microtubule-organizing center. We analyzed the effect of the cnn mutation on developing eyes to determine its role in photoreceptor morphogenesis. We found that Cnn is dispensable for retinal differentiation in eye imaginal discs during the larval stage. However, photoreceptors deficient in Cnn display dramatic morphogenesis defects including the mislocalization of Crumbs (Crb) and Bazooka (Baz) during mid-stage pupal eye development, suggesting that Cnn is specifically required for photoreceptor morphogenesis during pupal eye development. This role of Cnn in apical domain modulation was further supported by Cnn''s gain-of-function phenotype. Cnn overexpression in photoreceptors caused the expansion of the apical Crb membrane domain, Baz and adherens junctions (AJs).Conclusions/Significance
These results strongly suggest that the interaction of Baz and Cnn is essential for apical domain and AJ modulation during photoreceptor morphogenesis, but not for the initial photoreceptor differentiation in the Drosophila photoreceptor. 相似文献19.
Introduction
Transforming growth factor beta (TGFβ) plays a central role in morphogenesis, growth, and cell differentiation. This cytokine is particularly important in cartilage where it regulates cell proliferation and extracellular matrix synthesis. While the action of TGFβ on chondrocyte metabolism has been extensively catalogued, the modulation of specific genes that function as mediators of TGFβ signalling is poorly defined. In the current study, elements of the Smad component of the TGFβ intracellular signalling system and TGFβ receptors were characterised in human chondrocytes upon TGFβ1 treatment. 相似文献20.
Scott H Robertson Chris K Smith Anna L Langhans Sara E McLinden Matthew A Oberhardt Karoly R Jakab Bette Dzamba Douglas W DeSimone Jason A Papin Shayn M Peirce 《BMC systems biology》2007,1(1):46-15