scholarly journals Ligand-specific, transient interaction between integrins and calreticulin during cell adhesion to extracellular matrix proteins is dependent upon phosphorylation/dephosphorylation events

1999 ◽  
Vol 340 (1) ◽  
pp. 41-50 ◽  
Author(s):  
Marc G. COPPOLINO ◽  
Shoukat DEDHAR
Keyword(s):  
Okadaic Acid ◽  
Cell Attachment ◽  
Specific Interaction ◽  
Cell Types ◽  
Collagen Iv ◽  
Jurkat Cells ◽  
Mitogen Activated Protein Kinase ◽  
Collagen Type Iv ◽  
Type Iv ◽  
Mitogen Activated Protein

As transmembrane heterodimers, integrins bind to both extracellular ligands and intracellular proteins. We are currently investigating the interaction between integrins and the intracellular protein calreticulin. A prostatic carcinoma cell line (PC-3) was used to demonstrate that calreticulin can be found in the α3 immunoprecipitates of cells plated on collagen type IV, but not when plated on vitronectin. Conversely, αv immunoprecipitates contained calreticulin only when cells were plated on vitronectin, i.e. not when plated on collagen IV. The interactions between these integrins and calreticulin were independent of actin cytoskeleton assembly and were transient, being maximal approx. 10-30 min after the cells came into contact with the substrates prior to complete cell spreading and formation of firm adhesive contacts. We demonstrate that okadaic acid, an inhibitor of intracellular serine/threonine protein phosphatases, inhibited the α3β1-mediated adhesion of PC-3 cells to collagen IV and the α2β1-mediated attachment of Jurkat cells to collagen I. This inhibition by okadaic acid was accompanied by inhibition of the ligand-specific interaction of calreticulin with the respective integrins in the two cell types. Additionally, we found that pharmacological inhibition of mitogen-activated protein kinase kinase (MEK) resulted in prolongation of the calreticulin-integrin interaction, and enhancement of PC-3 cell attachment to collagen IV. We conclude that calreticulin interacts transiently with integrins during cell attachment and spreading. This interaction depends on receptor occupation, is ligand-specific, and can be modulated by protein phosphatase and MEK activity.

scholarly journals Serum Anti-Collagen IV IgM and IgG Antibodies as Indicators of Low Vascular Turnover of Collagen IV in Patients with Long-Term Complications of Type 2 Diabetes

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 900
Author(s):  
Krasimir Kostov ◽  
Alexander Blazhev
Keyword(s):  
Type 2 Diabetes ◽  
Serum Levels ◽  
Vascular Wall ◽  
Collagen Iv ◽  
Collagen Type Iv ◽  
Non Invasive ◽  
Type Iv ◽  
Antibody Levels

Thickening of the vascular basement membrane (BM) is a fundamental structural change in the small blood vessels in diabetes. Collagen type IV (CIV) is a major component of the BMs, and monitoring the turnover of this protein in type 2 diabetes (T2D) can provide important information about the mechanisms of vascular damage. The aim of the study was through the use of non-invasive biomarkers of CIV (autoantibodies, derivative peptides, and immune complexes) to investigate vascular turnover of CIV in patients with long-term complications of T2D. We measured serum levels of these biomarkers in 59 T2D patients with micro- and/or macrovascular complications and 20 healthy controls using an ELISA. Matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) were also tested. In the T2D group, significantly lower levels of CIV markers and significantly higher levels of MMP-2 and MMP-9 were found compared to controls. A significant positive correlation was found between IgM antibody levels against CIV and MMP-2. These findings suggest that vascular metabolism of CIV is decreased in T2D with long-term complications and show that a positive linear relationship exists between MMP-2 levels and CIV turnover in the vascular wall.

scholarly journals Selective expression of the scaffold protein JSAP1 in spermatogonia and spermatocytes

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 711-719 ◽  
Author(s):  
Munkhuu Bayarsaikhan ◽  
Akiko Shiratsuchi ◽  
Davaakhuu Gantulga ◽  
Yoshinobu Nakanishi ◽  
Katsuji Yoshioka
Keyword(s):  
Protein Kinase ◽  
Western Blotting ◽  
Cell Types ◽  
Mapk Signaling ◽  
Scaffold Protein ◽  
Mitogen Activated Protein Kinase ◽  
Interacting Protein ◽  
Early Postnatal Development ◽  
Mitogen Activated Protein ◽  
Signaling Modules

Scaffold proteins of mitogen-activated protein kinase (MAPK) intracellular signal transduction pathways mediate the efficient and specific activation of the relevant MAPK signaling modules. Previously, our group and others have identified c-Jun NH2-terminal kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1, also known as JNK-interacting protein 3) as a scaffold protein for JNK MAPK pathways. Although JSAP1 is expressed in the testis in adults, its expression during development has not been investigated. In addition, it is unknown which types of cells in the testis express the scaffold protein. Here, we examined the expression of JSAP1 in the testis of mice aged 14 days, 20 days, 6 weeks, and 12 weeks by immunohistochemistry and Western blotting. The specificity of the anti-JSAP1 antibody was evaluated from its reactivity to exogenously expressed JSAP1 and a structurally related protein, and by antigen-absorption experiments. The immunohistochemical analyses with the specific antibody showed that the JSAP1 protein was selectively expressed in the spermatogonia and spermatocytes, but not in other cell types, including spermatids and somatic cells, during development. However, not all spermatogonia and spermatocytes were immunopositive either, especially in the 12-week-old mouse testis. Furthermore, we found by Western blotting that the expression levels of JSAP1 protein vary during development; there is high expression until 6 weeks after birth, which approximately corresponds to the end of the first wave of spermatogenesis. Collectively, these results suggest that JSAP1 function may be important in spermatogenic cells during early postnatal development.

scholarly journals Chirality-Dependent Anti-Inflammatory Effect of Glutathione after Spinal Cord Injury in an Animal Model

2021 ◽  
Vol 14 (8) ◽  
pp. 792
Author(s):  
Seong-Jun Kim ◽  
Wan-Kyu Ko ◽  
Gong-Ho Han ◽  
Daye Lee ◽  
Yuhan Lee ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Therapeutic Potential ◽  
Specific Interaction ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Secondary Damage ◽  
Cord Injury ◽  
Mitogen Activated Protein ◽  
Pro Inflammatory Cytokines

Neuroinflammation forms a glial scar following a spinal cord injury (SCI). The injured axon cannot regenerate across the scar, suggesting permanent paraplegia. Molecular chirality can show an entirely different bio-function by means of chiral-specific interaction. In this study, we report that d-chiral glutathione (D-GSH) suppresses the inflammatory response after SCI and leads to axon regeneration of the injured spinal cord to a greater extent than l-chiral glutathione (L-GSH). After SCI, axon regrowth in D-GSH-treated rats was significantly increased compared with that in L-GSH-treated rats (*** p < 0.001). Secondary damage and motor function were significantly improved in D-GSH-treated rats compared with those outcomes in L-GSH-treated rats (** p < 0.01). Moreover, D-GSH significantly decreased pro-inflammatory cytokines and glial fibrillary acidic protein (GFAP) via inhibition of the mitogen-activated protein kinase (MAPK) signaling pathway compared with L-GSH (*** p < 0.001). In primary cultured macrophages, we found that D-GSH undergoes more intracellular interaction with activated macrophages than L-GSH (*** p < 0.001). These findings reveal a potential new regenerative function of chiral GSH in SCI and suggest that chiral GSH has therapeutic potential as a treatment of other diseases.

scholarly journals Type IV collagen immunoreactivity of basement membrane in inflammatory-regenerative and dysplastic lesions of the flat colonic mucosa

2003 ◽  
Vol 3 (1) ◽  
pp. 30-35
Author(s):  
Svjetlana Radović ◽  
Ivan Selak ◽  
Mirsad Babić ◽  
Željka Knežević ◽  
Zora Vukobrat-Bijedić
Keyword(s):  
Basement Membrane ◽  
Colon Adenocarcinoma ◽  
Normal Mucosa ◽  
Collagen Iv ◽  
Epithelial Dysplasia ◽  
Collagen Type Iv ◽  
Severe Dysplasia ◽  
Colon Mucosa ◽  
Mild Dysplasia ◽  
Type Iv

The aim of this research is to establish by immunohistochemistry if there is a change in the expression of collagen type IV, as a substitute of basement membrane, in development of epithelial dysplasia in chronically inflamed colon mucosa.Methods. Biopsy specimens from 270 patients were examined: 74 were classified as inflammatory-regenerative and 196 as dysplastic lesions. There were 108 cases of mild dysplasia, 58 cases of moderate and 30 cases severe dysplasia, respectively. Visualisation of collagen IV and its way of expression within basement membrane of glandular crypts was performed by immunohistochemistry and then compared with findings in normal colon mucosa and colon adenocarcinoma tissue.Results. Changes in the expression of collagen IV comprised of its focal irregularities, diffuse thinning and/or thickening, focal interruptions or its complete absence. Significant changes in the expression of collagen IV in relation to normal mucosa already occur in inflammatory-regenerative mucosa. In mild dysplasia, these changes are more intensive in relation to those in inflammatory altered mucosa as well as at severe dysplasia in relation to moderate dysplasia. Changes in the expression of collagen IV in severe dysplasia are significantly more serious than in moderate dysplasia but are identical to those in colon adenocarcinoma tissue.Conclusion. These findings suggest that change in the expression of collagen IV is in correlation to a degree of epithelial dysplasia that developed in flat chronically inflamed colon mucosa.

scholarly journals Expression of collagen type IV in human kidney during prenatal development

2020 ◽  
pp. 111-111
Author(s):  
Vladimir Petrovic ◽  
Ivan Nikolic ◽  
Marko Jovic ◽  
Vladimir Zivkovic ◽  
Miodrag Jocic ◽  
...  
Keyword(s):  
Type Iv Collagen ◽  
Collagen Type ◽  
Kidney Tissue ◽  
Volume Density ◽  
Collagen Iv ◽  
Basement Membranes ◽  
Collagen Type Iv ◽  
Type Iv ◽  
Metanephric Kidney ◽  
Collecting System

Background / Aim. Type IV collagen belongs to the group of non-fibrillar collagens and is an important component of the basement membranes where it accounts for approximately 50% of its structural elements. The aim of the paper was to describe the expression and distribution of collagen type IV in embryonic and fetal metanephric kidney, and to determine the volume density of collagen type IV in kidney tissue in each trimester of development. Methods. The material consisted of 19 human embryos/fetuses, in the gestational age from 8th to 37th week. Kidney tissue specimens were routinely processed to paraffin molds and stained with hematoxylin and eosin and immunohistochemically using polyclonal anti-collagen IV antibody. Stained slides were examined using light microscope and images of the selected areas, under different lens magnification were captured with digital camera. Volume density of collagen type IV was determined by using ImageJ 1.48v and a plugin of the software which inserted a grid system with 336 points. For the data comparison One-Way Analysis of Variance was used. Results. Strong collagen IV immunopositivity was seen in all specimens, with a distribution in the basement membranes of urinary bud, parietal leaf of Bowman?s capsule, glomerular basement membrane, basement membrane of interstitial blood vessels, and basement membranes of nephron tubules and collecting ducts. No statistically significant difference in the volume density of type IV collagen was found between the different trimesters of development. Conclusion. The synthesis and secretion of collagen type IV simultaneously follows the development of nephron structures, collecting system and blood vessels. The volume density of collagen type IV remains constant throughout all the trimesters of metanephric kidney development, indicating that it plays a crucial role in normal development of nephron and collecting system structures, as well as in maintaining the normal kidney function.

Role of integrins in melanocyte attachment and dendricity

1994 ◽  
Vol 107 (10) ◽  
pp. 2739-2748 ◽  
Author(s):  
M. Hara ◽  
M. Yaar ◽  
A. Tang ◽  
M.S. Eller ◽  
W. Reenstra ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Cell Biology ◽  
Type Iv Collagen ◽  
Cell Attachment ◽  
Pigment Cell ◽  
Cell Types ◽  
Dependent Manner ◽  
Flow Cytometry Analysis ◽  
Type Iv ◽  
Alpha V Beta 3

Integrins are a family of proteins known to mediate attachment of cells to extracellular matrix materials. The substratum specificity and cation dependence of specific integrin heterodimers have been extensively characterized, and to a lesser degree specialized roles in cell attachment versus dendricity have been defined in some cell types. In the past decade, melanocyte attachment rate and morphology have been found to have strong substratum dependence, suggesting a major role for integrins in these processes. In order to investigate this aspect of pigment cell biology, human newborn melanocytes were subjected to flow cytometry analysis and plated on a variety of substrata under conditions known to promote or block the binding of specific integrin pairs. Melanocyte attachment to laminin and type IV collagen was promoted by Mg2+ and Mn2+ but not by Ca2+, in the range of concentrations examined. However, dendrite outgrowth from melanocytes already attached on laminin or type IV collagen was promoted by Ca2+ to a far greater degree than by Mg2+, and Mn2+ had no effect on dendrite outgrowth. Flow cytometry analysis revealed that melanocytes expressed beta 1, alpha 2, alpha 3, alpha 5, alpha 6 and alpha v integrin subunits as well as the alpha v beta 3 heterodimer. The influence of substratum on the profile of integrin expression was minimal, but alpha 6 and beta 1 integrins were observed by confocal microscopy to be expressed over the entire cell surface, while alpha 2, alpha 5 and alpha v beta 3 integrins localized along dendritic processes or at their tips. In accordance with the implications of these distribution patterns, anti-beta 1 and anti-alpha 6 integrin monoclonal antibodies blocked melanocyte attachment to laminin, while anti-alpha 2, anti-alpha 5 and anti-alpha v beta 3 inhibited dendrite outgrowth but did not block substratum attachment on either laminin or type IV collagen. On the basis of these data and the known characteristics of integrin molecules, we conclude that melanocyte attachment to laminin is mediated primarily by alpha 6 beta 1 integrin in a Ca(2+)-independent, Mg(2+)- and/or Mn(2+)-dependent manner, while dendrite outgrowth on laminin and type IV collagen requires extracellular Ca2+ and is mediated by alpha v beta 3 as well as alpha 2 and alpha 5 integrins.

Serum enhancement of human endothelial cell attachment to and spreading on collagens I and IV does not require serum fibronectin or vitronectin

1990 ◽  
Vol 95 (2) ◽  
pp. 255-262
Author(s):  
W.D. Norris ◽  
J.G. Steele ◽  
G. Johnson ◽  
P.A. Underwood
Keyword(s):  
Endothelial Cell ◽  
Culture Medium ◽  
Type I Collagen ◽  
Cell Attachment ◽  
Cell Spreading ◽  
Human Endothelial Cell ◽  
Collagen Type Iv ◽  
Type I ◽  
Type Iv ◽  
Endothelial Cell Attachment

The initial attachment and spreading of endothelial cells from human umbilical artery onto type I collagen, type IV collagen or gelatin substrata was shown to be enhanced by inclusion of serum in the culture medium. To test whether this serum effect was mediated by adsorption of serum fibronectin or vitronectin onto the collagen, these adhesive glycoproteins were selectively removed from the serum prior to addition to the culture medium. The stimulatory effect of serum on human endothelial cell spreading on collagens I and IV was also observed with serum from which either fibronectin or vitronectin, or both, had been selectively removed. The stimulatory effect for cell spreading on gelatin was diminished by selective removal of serum fibronectin, but unaffected by removal of vitronectin. Human endothelial cell attachment and spreading onto tissue culture plastic was abolished by removal of vitronectin from the serum in the culture medium. These results emphasize that the native structure of collagens is required for serum-enhancement of human endothelial cell attachment and spreading on native collagen types I and IV, and show that on these substrata the stimulated adhesion and spreading are not dependent upon adsorption of serum fibronectin or vitronectin onto the collagen substratum.

scholarly journals Two Adjacent Docking Sites in the Yeast Hog1 Mitogen-Activated Protein (MAP) Kinase Differentially Interact with the Pbs2 MAP Kinase Kinase and the Ptp2 Protein Tyrosine Phosphatase

2008 ◽  
Vol 28 (7) ◽  
pp. 2481-2494 ◽  
Author(s):  
Yulia Murakami ◽  
Kazuo Tatebayashi ◽  
Haruo Saito
Keyword(s):  
Map Kinase ◽  
Binding Sites ◽  
Tyrosine Phosphatase ◽  
Specific Interaction ◽  
Binding Domain ◽  
Mitogen Activated Protein Kinase ◽  
Protein Map ◽  
Mitogen Activated Protein ◽  
Initial Interaction ◽  
Docking Sites

ABSTRACT Functional interactions between a mitogen-activated protein kinase (MAPK) and its regulators require specific docking interactions. Here, we investigated the mechanism by which the yeast osmoregulatory Hog1 MAPK specifically interacts with its activator, the MAPK kinase Pbs2, and its major inactivator, the protein phosphatase Ptp2. We found, in the N-terminal noncatalytic region of Pbs2, a specific Hog1-binding domain, termed HBD-1. We also defined two adjacent Pbs2-binding sites in Hog1, namely, the common docking (CD) domain and Pbs2-binding domain 2 (PBD-2). The PBD-2 docking site appears to be sterically blocked in the intact Hog1 molecule, but its affinity to Pbs2 is apparent in shorter fragments of Hog1. Both the CD and the PBD-2 docking sites are required for the optimal activation of Hog1 by Pbs2, and in the absence of both sites, Hog1 cannot be activated by Pbs2. These data suggest that the initial interaction of Pbs2 with the CD site might induce a conformational change in Hog1 so that the PBD-2 site becomes accessible. The CD and PBD-2 docking sites are also involved in the specific interaction between Hog1 and Ptp2 and govern the dynamic dephosphorylation of activated Hog1. Thus, the CD and the PBD-2 docking sites play critical roles in both the activation and inactivation of Hog1.

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