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Cancer Cell May 2009Transitions between epithelial and mesenchmal phenotypes play critical roles in normal development and cancer progression. In this issue of Cancer Cell, Evdokimova et...
Transitions between epithelial and mesenchmal phenotypes play critical roles in normal development and cancer progression. In this issue of Cancer Cell, Evdokimova et al. demonstrate that YB-1 regulates epithelial-mesenchyme transition (EMT) by inducing cap-independent translation of mRNAs encoding EMT-promoting factors and suppressing cap-dependent translation of mRNAs encoding growth-promoting factors.
Topics: Cell Differentiation; DNA-Binding Proteins; Epithelial Cells; Humans; Mesoderm; Nuclear Proteins; Protein Biosynthesis; RNA Caps; RNA, Messenger; Snail Family Transcription Factors; Transcription Factors; Y-Box-Binding Protein 1
PubMed: 19411064
DOI: 10.1016/j.ccr.2009.04.006 -
The Journal of Experimental Medicine Mar 2000We show that the mesenchymal cells that surround the 12-d mouse embryo thymus are necessary for T cell differentiation. Thus, epithelial lobes with attached mesenchyme...
We show that the mesenchymal cells that surround the 12-d mouse embryo thymus are necessary for T cell differentiation. Thus, epithelial lobes with attached mesenchyme generate all T cell populations in vitro, whereas lobes from which mesenchyme has been removed show poor lymphopoiesis with few cells progressing beyond the CD4(-)CD8(-) stage of development. Interestingly, thymic mesenchyme is derived from neural crest cells, and extirpation of the region of the neural crest involved results in impaired thymic development and craniofacial abnormalities similar to the group of clinical defects found in the DiGeorge syndrome. Previous studies have suggested an inductive effect of mesenchyme on thymic epithelial morphogenesis. However, we have found that mesenchyme-derived fibroblasts are still required for early T cell development in the presence of mature epithelial cells, and hence mesenchyme might have a direct role in lymphopoiesis. We provide an anatomical basis for the role of mesenchyme by showing that mesenchymal cells migrate into the epithelial thymus to establish a network of fibroblasts and associated extracellular matrix. We propose that the latter might be important for T cell development through integrin and/or cytokine interactions with immature thymocytes.
Topics: Animals; Cell Differentiation; Cell Movement; Epithelial Cells; Extracellular Matrix; Hematopoiesis, Extramedullary; Lymphoid Tissue; Mesoderm; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Organ Culture Techniques; Stem Cells; T-Lymphocyte Subsets; T-Lymphocytes; Thymus Gland
PubMed: 10727466
DOI: 10.1084/jem.191.6.1051 -
Mechanisms of Development Feb 2015During fin morphogenesis, several mesenchyme condensations occur to give rise to the dermal skeleton. Although each of them seems to create distinctive and unique... (Review)
Review
During fin morphogenesis, several mesenchyme condensations occur to give rise to the dermal skeleton. Although each of them seems to create distinctive and unique structures, they all follow the premises of the same morphogenetic principle. Holmgren's principle of delamination was first proposed to describe the morphogenesis of skeletal elements of the cranium, but Jarvik extended it to the development of the fin exoskeleton. Since then, some cellular or molecular explanations, such as the "flypaper" model (Thorogood et al.), or the evolutionary description by Moss, have tried to clarify this topic. In this article, we review new data from zebrafish studies to meet these criteria described by Holmgren and other authors. The variety of cell lineages involved in these skeletogenic condensations sheds light on an open discussion of the contributions of mesoderm- versus neural crest-derived cell lineages to the development of the head and trunk skeleton. Moreover, we discuss emerging molecular studies that are disclosing conserved regulatory mechanisms for dermal skeletogenesis and similarities during fin development and regeneration, which may have important implications in the potential use of the zebrafish fin as a model for regenerative medicine.
Topics: Animal Fins; Animals; Humans; Mesoderm; Models, Animal; Morphogenesis; Regeneration; Skull
PubMed: 25460362
DOI: 10.1016/j.mod.2014.11.002 -
Methods in Molecular Biology (Clifton,... 2000
Review
Topics: Animals; Heart; In Vitro Techniques; Mesoderm; Morphogenesis
PubMed: 10840695
DOI: 10.1385/1-59259-065-9:39 -
Genesis (New York, N.Y. : 2000) Mar 2009Brn4/Pou3f4 is a POU-domain transcription factor expressed in the otic mesenchyme that is required for the normal development of the inner ear. In this report, we...
Brn4/Pou3f4 is a POU-domain transcription factor expressed in the otic mesenchyme that is required for the normal development of the inner ear. In this report, we describe the isolation of an otic mesenchyme enhancer in the Brn4 gene. Subsequently, this enhancer was used to drive the expression of Cre recombinase in the otic mesenchyme of transgenic mice. When intercrossed with the ROSA reporter strain, R26R, ss-galactosidase expression is detected in several inner ear structures derived from otic mesenchyme, including the temporal bone, spiral ligament, spiral limbus, and mesenchyme underlying sensory epithelium of the utricle, saccule and semicircular canals. Thus, this Cre pedigree can induce conditional rearrangement of genes in the otic mesenchyme, and will serve as a powerful genetic tool to characterize the function of genes in the mesenchymal tissues of the inner ear.
Topics: Animals; Ear, Inner; Enhancer Elements, Genetic; Gene Expression Regulation, Developmental; Humans; Integrases; Mesoderm; Mice; Mice, Transgenic; Nerve Tissue Proteins; POU Domain Factors; Transgenes
PubMed: 19217071
DOI: 10.1002/dvg.20454 -
Cell Jun 2024Epithelial folding is a fundamental biological process that requires epithelial interactions with the underlying mesenchyme. In this issue of Cell, Huycke et al....
Epithelial folding is a fundamental biological process that requires epithelial interactions with the underlying mesenchyme. In this issue of Cell, Huycke et al. investigate intestinal villus formation. They discover that water-droplet-like behavior of mesenchymal cells drives their coalescence into uniformly patterned aggregates, which generate forces on the epithelium to initiate folding.
Topics: Animals; Humans; Epithelial Cells; Intestinal Mucosa; Mesoderm; Epithelium
PubMed: 38848672
DOI: 10.1016/j.cell.2024.04.045 -
Oncogene Mar 2002The mesenchyme plays a crucial regulatory role in organ formation and maintenance. However, comprehensive molecular characterization of these cells is lacking. We found...
The mesenchyme plays a crucial regulatory role in organ formation and maintenance. However, comprehensive molecular characterization of these cells is lacking. We found unexpectedly that primary mesenchyme, as well as mesenchymal cell clones, express T cell receptor (TCR)alphabeta mRNAs, lacking the variable region. Immunological and genetic evidence support the expression of a corresponding TCRbeta protein. Additionally, mRNAs encoding TCR complex components including CD3 and zeta chain are present. A relatively higher expression of the mesenchymal TCRbeta mRNA by cultured mesenchymal cell clones correlates with fast growth, whereas poorly expressing cells are slow growers and are contact inhibited. The clones that express relatively higher amount of the TCR mRNA exhibit an increased capacity to form tumors in nude mice. However, the expression of this mRNA in the mesenchyme is not per se leading to tumorigenesis, as demonstrated by primary mesenchyme that does not form tumors in mice while expressing moderate amounts of the TCR transcripts. The expression of mesencymal TCRbeta was confined to the G2/M phases of the cell cycle in the MBA-13 mesenchymal cell line. This cell cycle dependent expression, considered together with the correlation between growth properties and the level of TCR expression by cell clones, implies association of mesenchymal TCR with cell growth control.
Topics: Animals; Cell Cycle; Cell Division; Cell Line; Flow Cytometry; Gene Expression Profiling; HeLa Cells; Humans; Male; Mesoderm; Mice; Mice, Inbred C57BL; Mice, Nude; Neoplasm Transplantation; RNA, Messenger; Receptors, Antigen, T-Cell; Receptors, Antigen, T-Cell, alpha-beta; Reverse Transcriptase Polymerase Chain Reaction; Time Factors; Tumor Cells, Cultured
PubMed: 11960375
DOI: 10.1038/sj.onc.1205269 -
Nature Jan 1949
Topics: Extracellular Matrix; Hyaluronoglucosaminidase; Mesoderm
PubMed: 18107589
DOI: 10.1038/163184a0 -
Development, Growth & Differentiation Apr 2016To understand the roles of hesC and gcm during larval mesenchyme specification and differentiation in echinoids, we performed perturbation experiments for these genes in...
To understand the roles of hesC and gcm during larval mesenchyme specification and differentiation in echinoids, we performed perturbation experiments for these genes in two distantly related euechinoids, Hemicentrotus pulcherrimus and Scaphechinus mirabilis. The number of larval mesenchyme cells increased when the translation of hesC was inhibited, thereby suggesting that hesC has a general role in larval mesenchyme development. We confirmed previous results by demonstrating that gcm is involved in pigment cell differentiation. Simultaneous inhibition of the translation of hesC and gcm induced a significant increase in the number of skeletogenic cells, which suggests that gcm functions in skeletogenic fate repression. Based on these observations, we suggest that: (i) hesC participates in some general aspects of mesenchymal cell development; and (ii) gcm is involved in the mechanism responsible for the binary specification of skeletogenic and pigment cell fates.
Topics: Animals; Blastula; Cell Differentiation; Embryo, Nonmammalian; Gene Expression Profiling; Gene Expression Regulation, Developmental; In Situ Hybridization; Larva; Mesoderm; Morphogenesis; Reverse Transcriptase Polymerase Chain Reaction; Sea Urchins; Skeleton; Time Factors
PubMed: 27046223
DOI: 10.1111/dgd.12277 -
Gene Expression Patterns : GEP Mar 2015The molecular mechanism of the larval mesenchyme cell specification in echinoids has been well analyzed. However, most of the data have been provided by studies of a...
The molecular mechanism of the larval mesenchyme cell specification in echinoids has been well analyzed. However, most of the data have been provided by studies of a single group of echinoids, the order Camarodonta. Little is known about this mechanism in other echinoid orders. We examined the expression patterns of mesenchyme specification genes, micro1, hesC, alx1, tbr, ets1, cyp1, and gcm, in the two non-Camarodonta echinoids, Glyptocidaris crenularis and Echinocardium cordatum. We found that the expression patterns of some genes contained characteristics that were unique to one of the species; others were shared by the two species. Some of the shared characteristics of G. crenularis and E. cordatum are not found in the species belonging to Camarodonta, suggesting the derived status of this order. The expression of ets1 in E. cordatum aboral ectoderm is one of the molecular level modifications possibly related to an evolutionarily novel larval structure, the posterior process. Our results suggest that a considerable number of modifications in the mesenchyme specification mechanisms have been introduced during the echinoid evolution.
Topics: Animals; Embryo, Nonmammalian; Evolution, Molecular; Gene Expression Regulation, Developmental; Mesoderm; Proteins; Sea Urchins
PubMed: 25801498
DOI: 10.1016/j.gep.2015.03.003