Active role of embryonic facial epithelium: New evidence of cellular events in morphogenesis

Development ◽  
1981 ◽  
Vol 63 (1) ◽  
pp. 53-66
Author(s):  
Guillermo Millicovsky ◽  
Malcolm C. Johnston
Keyword(s):  
Epithelial Cells ◽  
Mouse Embryo ◽  
Cleft Lip ◽  
Normal Development ◽  
Active Role ◽  
Temporal Sequence ◽  
Cellular Events ◽  
Sequence Of Events ◽  
New Evidence

Epithelial cells of the C57B1/6J mouse embryo participate in a temporal sequence of events associated with the approximation, fusion and consolidation of components of the facial primordia into a definitive structure. These cells lose their surface microvilli, and after a brief period of quiescence they begin to fill the grooves separating facial constituents by producing a series of surface projections that increase in size and complexity as the process of fusion nears termination. Cessation of surface activity and the restoration of epithelial microvilli indicate the end of the temporal sequence. Significantly, the epithelial cells of rimary palates of embryos with genetically- and phenytoin-induced cleft lip remain unchanged and do not participate in fusion. This epithelial sequence has not been described previously and we suggest that all of its steps may be critical to the normal development of the mammalian face.

Cellular Samurai: katanin and the severing of microtubules

2000 ◽  
Vol 113 (16) ◽  
pp. 2821-2827 ◽  
Author(s):  
L. Quarmby
Keyword(s):  
Epithelial Cells ◽  
Essential Role ◽  
Aaa Atpase ◽  
C Elegans ◽  
Microtubule Severing ◽  
Biochemical Studies ◽  
New Evidence

Recent biochemical studies of the AAA ATPase, katanin, provide a foundation for understanding how microtubules might be severed along their length. These in vitro studies are complemented by a series of recent reports of direct in vivo observation of microtubule breakage, which indicate that the in vitro phenomenon of catalysed microtubule severing is likely to be physiological. There is also new evidence that microtubule severing by katanin is important for the production of non-centrosomal microtubules in cells such as neurons and epithelial cells. Although it has been difficult to establish the role of katanin in mitosis, new genetic evidence indicates that a katanin-like protein, MEI-1, plays an essential role in meiosis in C. elegans. Finally, new proteins involved in the severing of axonemal microtubules have been discovered in the deflagellation system of Chlamydomonas.

scholarly journals Role of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Epithelial–Mesenchymal Transition

2019 ◽  
Vol 20 (19) ◽  
pp. 4813 ◽  
Author(s):  
Sevindzh Kletukhina ◽  
Olga Neustroeva ◽  
Victoria James ◽  
Albert Rizvanov ◽  
Marina Gomzikova
Keyword(s):  
Epithelial Cells ◽  
Extracellular Vesicles ◽  
Intercellular Communication ◽  
Epithelial Mesenchymal Transition ◽  
Genetic Material ◽  
Biologically Active ◽  
Target Cells ◽  
Mesenchymal Transition ◽  
New Evidence

Epithelial–mesenchymal transition (EMT) is a process that takes place during embryonic development, wound healing, and under some pathological processes, including fibrosis and tumor progression. The molecular changes occurring within epithelial cells during transformation to a mesenchymal phenotype have been well studied. However, to date, the mechanism of EMT induction remains to be fully elucidated. Recent findings in the field of intercellular communication have shed new light on this process and indicate the need for further studies into this important mechanism. New evidence supports the hypothesis that intercellular communication between mesenchymal stroma/stem cells (MSCs) and resident epithelial cells plays an important role in EMT induction. Besides direct interactions between cells, indirect paracrine interactions by soluble factors and extracellular vesicles also occur. Extracellular vesicles (EVs) are important mediators of intercellular communication, through the transfer of biologically active molecules, genetic material (mRNA, microRNA, siRNA, DNA), and EMT inducers to the target cells, which are capable of reprogramming recipient cells. In this review, we discuss the role of intercellular communication by EVs to induce EMT and the acquisition of stemness properties by normal and tumor epithelial cells.

scholarly journals Expression and Secretion of CXCL-8 and CXCL-10 FromMycobacterium BovisBCG-Infected Human Epithelial Cells: Role of IL-4

2006 ◽  
Vol 2006 ◽  
pp. 1-6 ◽  
Author(s):  
Patricia Méndez-Samperio ◽  
Elena Miranda ◽  
Abraham Vázquez
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Mrna Level ◽  
Neutralizing Antibody ◽  
Active Role ◽  
Polymerase Chain Reaction Method ◽  
Enzyme Linked Immunosorbent Assay ◽  
Chemokine Production ◽  
Human Epithelial Cells

CXC chemokine release can be modulated by Th2-derived cytokines. Interleukin(IL)-4 is one of the cytokines that are the hallmark of the Th-2 response, and plays an important role in human tuberculosis. In the current study, we investigated the effect of IL-4 on chemokine production by human epithelial cells infected withMycobacterium bovisbacillus calmette-guérin (BCG). Gene expression of CXCL-8 and CXCL-10 was determined by the reverse transcription (RT)-polymerase chain reaction method. The levels of immunoreactive CXCL-8 and CXCL-10 were determined by enzyme-linked immunosorbent assay. We found that, althoughM. bovisBCG induced gene expression of CXCL-8 and CXCL-10 inM. bovisBCG-infected human epithelial cells, CXCL-8 mRNA level was significantly reduced by IL-4, whereas no significant effect of IL-4 was observed on CXCL10 mRNA level. In addition, IL-4 decreased CXCL-8 (in a graded and significant manner) but not CXCL-10 secretion. These results were further confirmed, since a significant reversion was obtained with a neutralizing antibody to human IL-4, whereas an isotype-matched control antibody had no significant effect on CXCL-8 secretion. Furthermore, we found a similar effect of IL-4 onM. bovisBCG-induced CXCL-8 and CXCL-10 secretion by using other human epithelial A549 cell line. Collectively, these data demonstrate thatM. bovisBCG-infected human epithelial cells can have an active role in a local inflammatory immune response via the secretion of CXC chemokines which can be selectively regulated by Th2-derived cytokines.

scholarly journals Disrupted IRF6-NME1/2 Complexes as a Cause of Cleft Lip/Palate

2017 ◽  
Vol 96 (11) ◽  
pp. 1330-1338 ◽  
Author(s):  
M.T. Parada-Sanchez ◽  
E.Y. Chu ◽  
L.L. Cox ◽  
S.S. Undurty ◽  
J.M. Standley ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cleft Lip ◽  
Missense Mutations ◽  
C Terminus ◽  
Interferon Regulatory Factor 6 ◽  
Cleft Lip Palate ◽  
Bona Fide ◽  
Partner Proteins

Mutations and common polymorphisms in interferon regulatory factor 6 ( IRF6) are associated with both syndromic and nonsyndromic forms of cleft lip/palate (CLP). To date, much of the focus on this transcription factor has been on identifying its direct targets and the gene regulatory network in which it operates. Notably, however, IRF6 is found predominantly in the cytoplasm, with its import into the nucleus tightly regulated like other members of the IRF family. To provide further insight into the role of IRF6 in the pathogenesis of CLP, we sought to identify direct IRF6 protein interactors using a combination of yeast 2-hybrid screens and co-immunoprecipitation assays. Using this approach, we identified NME1 and NME2, well-known regulators of Rho-type GTPases, E-cadherin endocytosis, and epithelial junctional remodeling, as bona fide IRF6 partner proteins. The NME proteins co-localize with IRF6 in the cytoplasm of primary palatal epithelial cells in vivo, and their interaction with IRF6 is significantly enhanced by phosphorylation of key serine residues in the IRF6 C-terminus. Furthermore, CLP associated IRF6 missense mutations disrupt the ability of IRF6 to bind the NME proteins and result in elevated activation of Rac1 and RhoA, compared to wild-type IRF6, when ectopically expressed in 293T epithelial cells. Significantly, we also report the identification of 2 unique missense mutations in the NME proteins in patients with CLP (NME1 R18Q in an IRF6 and GRHL3 mutation-negative patient with van der Woude syndrome and NME2 G71V in a patient with nonsyndromic CLP). Both variants disrupted the ability of the respective proteins to interact with IRF6. The data presented suggest an important role for cytoplasmic IRF6 in regulating the availability or localization of the NME1/2 complex and thus the dynamic behavior of epithelia during lip/palate development.

Involvement of programmed cell death in morphogenesis of the vertebrate inner ear

Development ◽  
1997 ◽  
Vol 124 (12) ◽  
pp. 2451-2461 ◽  
Author(s):  
D.M. Fekete ◽  
S.A. Homburger ◽  
M.T. Waring ◽  
A.E. Riedl ◽  
L.F. Garcia
Keyword(s):  
Cell Death ◽  
Epithelial Cells ◽  
Programmed Cell Death ◽  
Inner Ear ◽  
Three Dimensional ◽  
Semicircular Canals ◽  
Otic Vesicle ◽  
New Evidence

An outstanding challenge in developmental biology is to reveal the mechanisms underlying the morphogenesis of complex organs. A striking example is the developing inner ear of the vertebrate, which acquires a precise three-dimensional arrangement of its constituent epithelial cells to form three semicircular canals, a central vestibule and a coiled cochlea (in mammals). In generating a semicircular canal, epithelial cells seem to ‘disappear’ from the center of each canal. This phenomenon has been variously explained as (i) transdifferentiation of epithelium into mesenchyme, (ii) absorption of cells into the expanding canal or (iii) programmed cell death. In this study, an in situ DNA-end labeling technique (the TUNEL protocol) was used to map regions of cell death during inner ear morphogenesis in the chicken embryo from embryonic days 3.5-10. Regions of cell death previously identified in vertebrate ears have been confirmed, including the ventromedial otic vesicle, the base of the endolymphatic duct and the fusion plates of the semicircular canals. New regions of cell death are also described in and around the sensory organs. Reducing normal death using retrovirus-mediated overexpression of human bcl-2 causes abnormalities in ear morphogenesis: hollowing of the center of each canal is either delayed or fails entirely. These data provide new evidence to explain the role of cell death in morphogenesis of the semicircular canals.

scholarly journals Melatonin and Myo-Inositol: Supporting Reproduction from the Oocyte to Birth

2021 ◽  
Vol 22 (16) ◽  
pp. 8433
Author(s):  
Michele Russo ◽  
Gianpiero Forte ◽  
Mario Montanino Oliva ◽  
Antonio Simone Laganà ◽  
Vittorio Unfer
Keyword(s):  
Fertilization Rate ◽  
Cellular Events ◽  
Sequence Of Events ◽  
Embryo Formation ◽  
New Birth ◽  
Reproduction Process ◽  
Human Reproductive ◽  
Representative Member ◽  
Molecular Crosstalk

Human pregnancy is a sequence of events finely tuned by several molecular interactions that come with a new birth. The precise interlocking of these events affecting the reproductive system guarantees safe embryo formation and fetal development. In this scenario, melatonin and myo-inositol seem to be pivotal not only in the physiology of the reproduction process, but also in the promotion of positive gestational outcomes. Evidence demonstrates that melatonin, beyond the role of circadian rhythm management, is a key controller of human reproductive functions. Similarly, as the most representative member of the inositol’s family, myo-inositol is essential in ensuring correct advancing of reproductive cellular events. The molecular crosstalk mediated by these two species is directly regulated by their availability in the human body. To date, biological implications of unbalanced amounts of melatonin and myo-inositol in each pregnancy step are growing the idea that these molecules actively contribute to reduce negative outcomes and improve the fertilization rate. Clinical data suggest that melatonin and myo-inositol may constitute an optimal dietary supplementation to sustain safe human gestation and a new potential way to prevent pregnancy-associated pathologies.

The role of cell adhesion in the synchronization and orientation of polarization in 8-cell mouse blastomeres

Development ◽  
1986 ◽  
Vol 93 (1) ◽  
pp. 239-255
Author(s):  
Martin H. Johnson ◽  
Bernard Maro ◽  
Masatoshi Takeichi
Keyword(s):  
Cell Adhesion ◽  
Mouse Embryo ◽  
Normal Development ◽  
Early Event ◽  
Early Mouse Embryo ◽  
Adhesion System ◽  
Dependent Cell ◽  
Temporal And Spatial ◽  
Early Mouse

A detailed investigation into the activity of the homotypic, Ca2+-dependent cell-cell adhesion system (CDS) in the early mouse embryo has revealed its involvement in (i) the synchronizing of the time of polarization of 8-cell blastomeres, and (ii) the orienting of the axis of polarization. Since polarization marks an important and early event in the process of cell diversification in the mouse embryo, it is concluded that the CDS provides an important component of the system by which the temporal and spatial elements of normal development are integrated.

New evidence for the role of cystathionine beta-synthase in non-syndromic cleft lip with or without cleft palate

2011 ◽  
Vol 119 (3) ◽  
pp. 193-197 ◽  
Author(s):  
Marcella Martinelli ◽  
Elena Masiero ◽  
Francesco Carinci ◽  
Paolo G. Morselli ◽  
Furio Pezzetti ◽  
...  
Keyword(s):  
Cleft Palate ◽  
Cleft Lip ◽  
Cystathionine Beta Synthase ◽  
New Evidence

Effect of Calcium on the Growth and Differentiation of Cultured Rat Esophageal Epithelial Cells

1982 ◽  
Vol 40 ◽  
pp. 132-133
Author(s):  
W.T. Gunning ◽  
M.R. Marino ◽  
M.S. Babcock ◽  
G.D. Stoner
Keyword(s):  
Epithelial Cells ◽  
Cell Types ◽  
Replication Rate ◽  
Enzymatic Dissociation ◽  
Growth Assay ◽  
Epidermal Growth ◽  
Fetal Bovine ◽  
Esophageal Epithelial Cells ◽  
Cellular Replication

The role of calcium in modulating cellular replication and differentiation has been described for various cell types. In the present study, the effects of Ca++ on the growth and differentiation of cultured rat esophageal epithelial cells was investigated.Epithelial cells were isolated from esophagi taken from 8 week-old male CDF rats by the enzymatic dissociation method of Kaighn. The cells were cultured in PFMR-4 medium supplemented with 0.25 mg/ml dialyzed fetal bovine serum, 5 ng/ml epidermal growth factor, 10-6 M hydrocortisone 10-6 M phosphoethanolamine, 10-6 M ethanolamine, 5 pg/ml insulin, 5 ng/ml transferrin, 10 ng/ml cholera toxin and 50 ng/ml garamycin at 36.5°C in a humidified atmosphere of 3% CO2 in air. At weekly intervals, the cells were subcultured with a solution containing 1% polyvinylpyrrolidone, 0.01% EGTA, and 0.05% trypsin. After various passages, the replication rate of the cells in PFMR-4 medium containing from 10-6 M to 10-3 M Ca++ was determined using a clonal growth assay.

Role of spectrin in membrane fusion and in shape change of human erythrocyte ghost

1978 ◽  
Vol 36 (2) ◽  
pp. 328-329
Author(s):  
Hideo Hayashi ◽  
Yoshikazu Hirai ◽  
John T. Penniston
Keyword(s):  
Conformational Changes ◽  
Human Erythrocyte ◽  
Shape Change ◽  
Membrane Surface ◽  
Slight Modification ◽  
Active Role ◽  
Main Role ◽  
Bank Blood ◽  
Human Erythrocyte Ghost

Spectrin is a membrane associated protein most of which properties have been tentatively elucidated. A main role of the protein has been assumed to give a supporting structure to inside of the membrane. As reported previously, however, the isolated spectrin molecule underwent self assemble to form such as fibrous, meshwork, dispersed or aggregated arrangements depending upon the buffer suspended and was suggested to play an active role in the membrane conformational changes. In this study, the role of spectrin and actin was examined in terms of the molecular arrangements on the erythrocyte membrane surface with correlation to the functional states of the ghosts.Human erythrocyte ghosts were prepared from either freshly drawn or stocked bank blood by the method of Dodge et al with a slight modification as described before. Anti-spectrin antibody was raised against rabbit by injection of purified spectrin and partially purified.

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