scholarly journals Septins Coordinate with Microtubules and Actin to Initiate Cell Morphogenesis

2019 ◽  
Author(s):  
Diana Bogorodskaya ◽  
Lee A. Ligon
Keyword(s):  
Branching Morphogenesis ◽  
Response To Treatment ◽  
Cell Morphogenesis ◽  
Microtubule Organization ◽  
Basal Surface ◽  
Linear Rate ◽  
Epithelial Sheet ◽  
District Role ◽  
Hepatocyte Growth ◽  
Cytoskeletal System

AbstractMany organs are formed by a process of branching morphogenesis, which begins with the formation of cytoplasmic extensions from the basal surface of polarized cells in an epithelial sheet. To study this process, we used a system of polarized epithelial spheroids, which emit cytoplasmic extensions in response to treatment with hepatocyte growth factor. We found that these extensions contain both actin and microtubules, but also septins, which are localized to microtubule bundles and appear to be important in maintaining microtubule organization. We found that these extensions are highly dynamic and form at a non-linear rate. We also demonstrated that the coordinated activity of microtubules, actin, and septins is necessary for the formation and dynamic behavior of extensions. Each cytoskeletal system plays a district role in this process, with microtubules enabling persistent growth of the extensions, actin enabling extension dynamics, and septins organizing microtubules in the extensions and supporting the extension formation. Together, our data offer insights into the dynamics of early morphogenic extensions and the distinct, but coordinated, roles of cytoskeleton in early morphogenesis.

scholarly journals LIM kinase regulation of cytoskeletal dynamics is required for salivary gland branching morphogenesis

2014 ◽  
Vol 25 (16) ◽  
pp. 2393-2407 ◽  
Author(s):  
Shayoni Ray ◽  
Joseph A. Fanti ◽  
Diego P. Macedo ◽  
Melinda Larsen
Keyword(s):  
Salivary Gland ◽  
Late Stage ◽  
Ex Vivo ◽  
Branching Morphogenesis ◽  
Microtubule Assembly ◽  
Microtubule Organization ◽  
Lim Kinase ◽  
Cytoskeletal Dynamics ◽  
Assembly Factor ◽  
Focal Adhesion Protein

Coordinated actin microfilament and microtubule dynamics is required for salivary gland development, although the mechanisms by which they contribute to branching morphogenesis are not defined. Because LIM kinase (LIMK) regulates both actin and microtubule organization, we investigated the role of LIMK signaling in mouse embryonic submandibular salivary glands using ex vivo organ cultures. Both LIMK 1 and 2 were necessary for branching morphogenesis and functioned to promote epithelial early- and late-stage cleft progression through regulation of both microfilaments and microtubules. LIMK-dependent regulation of these cytoskeletal systems was required to control focal adhesion protein–dependent fibronectin assembly and integrin β1 activation, involving the LIMK effectors cofilin and TPPP/p25, for assembly of the actin- and tubulin-based cytoskeletal systems, respectively. We demonstrate that LIMK regulates the early stages of cleft formation—cleft initiation, stabilization, and progression—via establishment of actin stability. Further, we reveal a novel role for the microtubule assembly factor p25 in regulating stabilization and elongation of late-stage progressing clefts. This study demonstrates the existence of multiple actin- and microtubule-dependent stabilization steps that are controlled by LIMK and are required in cleft progression during branching morphogenesis.

scholarly journals Angiogenesis-Related Cytokines, RANKL, and Osteoprotegerin in Multiple Myeloma Patients in relation to Clinical Features and Response to Treatment

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
K. Sfiridaki ◽  
C. A. Pappa ◽  
G. Tsirakis ◽  
P. Kanellou ◽  
M. Kaparou ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Growth Factor ◽  
Serum Levels ◽  
Response To Treatment ◽  
Disease Stage ◽  
Vascular Endothelial ◽  
Newly Diagnosed ◽  
Plateau Phase ◽  
Endothelial Growth Factor ◽  
Hepatocyte Growth

An essential cytokine system for the osteoclast biology in multiple myeloma (MM) consists of the receptor of activator of NF-κB ligand (RANKL), its receptor (RANK), and the soluble decoy receptor, osteoprotegerin (OPG). Myeloma cells cause imbalance in OPG/RANKL interactions. We measured serum levels of OPG, soluble (s) RANKL, sRANKL/OPG ratio, markers of disease activity [LDH, CRP, interleukin-6 (IL-6),β2-microglobulin (B2M)], and angiogenic factors [hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF)], in 54 newly diagnosed MM patients and in 25 of them in plateau phase. All the above values were higher in MM patients compared to controls and decreased in plateau phase. sRANKL and RANKL/OPG were higher with advancing disease stage and skeletal grade. Significant correlations were found among RANKL and RANKL/OPG with HGF, LDH, VEGF, IL-6, and B2M. In conclusion, RANKL and OPG play significant roles in MM pathophysiology, as regulators of bone turnover and mediators of angiogenesis.

scholarly journals Hepatocyte Growth Factor Activator Inhibitor Type 1 (HAI-1) Is Required for Branching Morphogenesis in the Chorioallantoic Placenta

2005 ◽  
Vol 25 (13) ◽  
pp. 5687-5698 ◽  
Author(s):  
Hiroyuki Tanaka ◽  
Koki Nagaike ◽  
Naoki Takeda ◽  
Hiroshi Itoh ◽  
Kazuyo Kohama ◽  
...  
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Serine Proteinase ◽  
Branching Morphogenesis ◽  
Hepatocyte Growth Factor Activator ◽  
Chorioallantoic Placenta ◽  
Inhibitor Type ◽  
Activator Inhibitor Type ◽  
Hepatocyte Growth

ABSTRACT Hepatocyte growth factor activator inhibitor type 1 (HAI-1) is a membrane-associated Kunitz-type serine proteinase inhibitor that was initially identified as a potent inhibitor of hepatocyte growth factor activator. HAI-1 is also a cognate inhibitor of matriptase, a membrane-associated serine proteinase. HAI-1 is expressed predominantly in epithelial cells in the human body. Its mRNA is also abundant in human placenta, with HAI-1 specifically expressed by villous cytotrophoblasts. In order to address the precise roles of HAI-1 in vivo, we generated HAI-1 mutant mice by homozygous recombination. Heterozygous HAI-1 +/− mice underwent normal organ development. However, homozygous HAI-1 −/− mice experienced embryonic lethality which became evident at embryonic day 10.5 postcoitum (E10.5). As early as E9.5, HAI-1 −/− embryos showed growth retardation that did not reflect impaired cell proliferation but resulted instead from failed placental development and function. Histological analysis revealed severely impaired formation of the labyrinth layer, in contrast all other placental layers, such as the spongiotrophoblast layer and giant cell layer, which were formed. Our results indicate that mouse HAI-1 is essential for branching morphogenesis in the chorioallantoic placenta and lack of HAI-1 function may result in placental failure.

Loss of MDCK cell alpha 2 beta 1 integrin expression results in reduced cyst formation, failure of hepatocyte growth factor/scatter factor-induced branching morphogenesis, and increased apoptosis

1995 ◽  
Vol 108 (11) ◽  
pp. 3531-3540 ◽  
Author(s):  
E.U. Saelman ◽  
P.J. Keely ◽  
S.A. Santoro
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Antisense Rna ◽  
Mdck Cells ◽  
Cyst Formation ◽  
Branching Morphogenesis ◽  
Integrin Subunit ◽  
Scatter Factor ◽  
Beta 1 Integrin ◽  
Hepatocyte Growth

Cellular interactions with collagen in a model of kidney tubulogenesis were investigated using Madin-Darby canine kidney (MDCK) cells in an in vitro morphogenetic system. MDCK cells adhered to collagen types I and IV in a Mg(2+)-dependent manner, typical of the alpha 2 beta 1 integrin. Collagen-Sepharose affinity chromatography and immunoblotting demonstrated the presence and collagen binding activity of the alpha 2 beta 1 integrin on MDCK cells. To assess the function of alpha 2 beta 1 integrin, MDCK cells were transfected with a plasmid pRSV alpha 2′ which allowed the expression of alpha 2-integrin subunit antisense RNA. Three G418-resistant clones showing reduced adhesion to collagen, stable genomic integration of the antisense construct, decreased alpha 2-integrin subunit mRNA and decreased alpha 2-integrin subunit protein expression were selected for analysis in morphogenetic experiments. MDCK cells and plasmid-only control transfectants, cultured in three-dimensional collagen type I gels, showed normal cyst formation, whereas the antisense RNA transfectants showed increased apoptosis and formed small rudimentary cysts. Stimulation with hepatocyte growth factor/scatter factor-containing 3T3 fibroblast-conditioned medium or recombinant hepatocyte growth factor/scatter factor resulted in extensive branching of the preformed control cysts whereas the surviving small cysts formed by antisense expressing cells increased in size but failed to elongate and branch upon stimulation. We conclude that alpha 2 beta 1 integrin collagen interactions play a crucial role in the hepatocyte growth factor/scatter factor-induced tubulogenesis and branching morphogenesis of MDCK cells in collagen gels as well as an important role in cell survival.

scholarly journals Roles of hepatocyte growth factor/scatter factor and the met receptor in the early development of the metanephros.

1995 ◽  
Vol 128 (1) ◽  
pp. 171-184 ◽  
Author(s):  
A S Woolf ◽  
M Kolatsi-Joannou ◽  
P Hardman ◽  
E Andermarcher ◽  
C Moorby ◽  
...  
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Early Development ◽  
Branching Morphogenesis ◽  
Mesenchymal Cells ◽  
T Antigen ◽  
Ureteric Bud ◽  
Scatter Factor ◽  
Hepatocyte Growth

Several lines of evidence suggest that hepatocyte growth factor/scatter factor (HGF/SF), a soluble protein secreted by embryo fibroblasts and several fibroblast lines, may elicit morphogenesis in adjacent epithelial cells. We investigated the role of HGF/SF and its membrane receptor, the product of the c-met protooncogene, in the early development of the metanephric kidney. At the inception of the mouse metanephros at embryonic day 11, HGF/SF was expressed in the mesenchyme, while met was expressed in both the ureteric bud and the mesenchyme, as assessed by reverse transcription PCR, in situ hybridization, and immunohistochemistry. To further investigate the expression of met in renal mesenchyme, we isolated 13 conditionally immortal clonal cell lines from transgenic mice expressing a temperature-sensitive mutant of the SV-40 large T antigen. Five had the HGF/SF+/met+ phenotype and eight had the HGF/SF-/met+ phenotype. None had the HGF/SF+/met- nor the HGF/SF-/met- phenotypes. Thus the renal mesenchyme contains cells that express HGF/SF and met or met alone. When metanephric rudiments were grown in serum-free organ culture, anti-HGF/SF antibodies (a) inhibited the differentiation of metanephric mesenchymal cells into the epithelial precursors of the nephron; (b) increased cell death within the renal mesenchyme; and (c) perturbed branching morphogenesis of the ureteric bud. These data provide the first demonstration for coexpression of the HGF/SF and met genes in mesenchymal cells during embryonic development and also imply an autocrine and/or paracrine role for HGF/SF and met in the survival of the renal mesenchyme and in the mesenchymal-epithelial transition that occurs during nephrogenesis. They also confirm the postulated paracrine role of HGF/SF in the branching of the ureteric bud.

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