Expression of Discoidin Domain Receptor 2 (DDR2) in the Developing Heart

2005 ◽  
Vol 11 (3) ◽  
pp. 260-267 ◽  
Author(s):  
Mary O. Morales ◽  
Robert L. Price ◽  
Edie C. Goldsmith

Interactions between cells and the surrounding extracellular matrix are important for a number of developmental events. In the heart, cardiac fibroblasts produce the majority of extracellular matrix proteins, particularly collagen types I and III. Cells originating from the proepicardial organ migrate over the surface of the heart, invade the underlying myocardium and ultimately give rise to smooth muscle cells, fibroblasts, and coronary endothelium. Although integrin expression in the developing heart has been well characterized, the expression of Discoidin Domain Receptor 2 (DDR2) remains to be defined. Using confocal microscopy, the expression of DDR2 was examined at several points during cardiac development. Initially, DDR2 expression was detected on the epicardial surface of the heart and on endothelial and mesenchymal cells within the cardiac cushions. As development progressed, DDR2 expression increased at localized regions in the apex and atrioventricular sulcus, although this expression decreased from epicardial to endocardial surface. Eventually, DDR2 expression spanned the myocardial free wall and was detected within the septum. Not until postnatal development was DDR2 expression detected uniformly throughout the myocardium and this distribution was maintained in the adult heart. In summary, the data presented demonstrate that the distribution of DDR2-positive cells changes within the heart during development.

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Laura Lacerda Coelho ◽  
Isabela Resende Pereira ◽  
Mirian Claudia de Souza Pereira ◽  
Liliane Mesquita ◽  
Joseli Lannes-Vieira ◽  
...  

2013 ◽  
Vol 135 (7) ◽  
Author(s):  
Kelly Elizabeth Sullivan ◽  
Lauren Deems Black

The extracellular matrix is no longer considered a static support structure for cells but a dynamic signaling network with the power to influence cell, tissue, and whole organ physiology. In the myocardium, cardiac fibroblasts are the primary cell type responsible for the synthesis, deposition, and degradation of matrix proteins, and they therefore play a critical role in the development and maintenance of functional heart tissue. This review will summarize the extensive research conducted in vivo and in vitro, demonstrating the influence of both physical and chemical stimuli on cardiac fibroblasts and how these interactions impact both the extracellular matrix and, by extension, cardiomyocytes. This work is of considerable significance, given that cardiovascular diseases are marked by extensive remodeling of the extracellular matrix, which ultimately impairs the functional capacity of the heart. We seek to summarize the unique role of cardiac fibroblasts in normal cardiac development and the most prevalent cardiac pathologies, including congenital heart defects, hypertension, hypertrophy, and the remodeled heart following myocardial infarction. We will conclude by identifying existing holes in the research that, if answered, have the potential to dramatically improve current therapeutic strategies for the repair and regeneration of damaged myocardium via mechanotransductive signaling.


2000 ◽  
Vol 68 (9) ◽  
pp. 5210-5217 ◽  
Author(s):  
Sreedhar R. Nallapareddy ◽  
Kavindra V. Singh ◽  
Ruay-Wang Duh ◽  
George M. Weinstock ◽  
Barbara E. Murray

ABSTRACT Our previous work reported that most Enterococcus faecalis strains adhered to the extracellular matrix proteins collagen types I and IV and laminin after growth at 46°C, but not 37°C, and we subsequently identified an E. faecalissequence, ace, that encodes a bacterial adhesin similar to the collagen binding protein Cna of Staphylococcus aureus. In this study, we examined the diversity of E. faecalis-specific ace gene sequences among different isolates obtained from various geographic regions as well as from various clinical sources. A comparison of nucleotide and deduced amino acid sequences of Ace from nine E. faecalis strains identified a highly conserved N-terminal A domain, followed by a variable B domain which contains two to five repeats of 47 amino acids in tandem array, preceded by a 20-amino-acid partial repeat. Using 17 other strains collected worldwide, the 5′ region of acethat encodes the A domain was sequenced, and these sequences showed ≥97.5% identity. Among the previously reported five amino acids critical for collagen binding by Cna of S. aureus, four were found to be identical in Ace from all strains tested. Polyclonal immune rabbit serum prepared against recombinant Ace A derived fromE. faecalis strain OG1RF detected Ace in mutanolysin extracts of seven of nine E. faecalis strains after growth at 46°C; Ace was detected in four different molecular sizes that correspond to the variation in the B repeat region. To determine if there was any evidence to indicate that Ace might be produced under physiological conditions, we quantitatively assayed sera collected from patients with enterococcal infections for the presence of anti-Ace A antibodies. Ninety percent of sera (19 of 21) from patients withE. faecalis endocarditis showed reactivity with titers from 1:32 to >1:1,024; the only 2 sera which lacked antibodies to Ace A had considerably lower titers of antibodies to other E. faecalis antigens as well. Human-derived, anti-Ace A immunoglobulins G purified from an E. faecalis endocarditis patient serum inhibited adherence of 46°C-grown E. faecalis OG1RF to collagen types I and IV and laminin. In conclusion, these results show that ace is highly conserved among isolates of E. faecalis, with at least four variants related to the differences in the B domain, is expressed by different strains during infection in humans, and human-derived antibodies can block adherence to these extracellular matrix proteins.


2014 ◽  
Vol 307 (5) ◽  
pp. H773-H781 ◽  
Author(s):  
Randy T. Cowling ◽  
Seon Ju Yeo ◽  
In Jai Kim ◽  
Joong Il Park ◽  
Yusu Gu ◽  
...  

Discoidin domain receptor 2 (DDR2) is a fibrillar collagen receptor that is expressed in mesenchymal cells throughout the body. In the heart, DDR2 is selectively expressed on cardiac fibroblasts. We generated a germline DDR2 knockout mouse and used this mouse to examine the role of DDR2 deletion on heart structure and function. Echocardiographic measurements from null mice were consistent with those from a smaller heart, with reduced left ventricular chamber dimensions and little change in wall thickness. Fractional shortening appeared normal. Left ventricular pressure measurements revealed mild inotropic and lusitropic abnormalities that were accentuated by dobutamine infusion. Both body and heart weights from 10-wk-old male mice were ∼20% smaller in null mice. The reduced heart size was not simply due to reduced body weight, since cardiomyocyte lengths were atypically shorter in null mice. Although normalized cardiac collagen mass (assayed by hydroxyproline content) was not different in null mice, the collagen area fraction was statistically higher, suggesting a reduced collagen density from altered collagen deposition and cross-linking. Cultured cardiac fibroblasts from null mice deposited collagen at a slower rate than wild-type littermates, possibly due to the expression of lower prolyl 4-hydroxylase α-isoform 1 enzyme levels. We conclude that genetic deletion of the DDR2 collagen receptor alters cardiac fibroblast function. The resulting perturbations in collagen deposition can influence the structure and function of mature cardiomyocytes.


2021 ◽  
Vol 22 (17) ◽  
pp. 9343
Author(s):  
Allen Sam Titus ◽  
Harikrishnan Venugopal ◽  
Mereena George Ushakumary ◽  
Mingyi Wang ◽  
Randy T. Cowling ◽  
...  

This study probed the largely unexplored regulation and role of fibronectin in Angiotensin II-stimulated cardiac fibroblasts. Using gene knockdown and overexpression approaches, Western blotting, and promoter pull-down assay, we show that collagen type I-activated Discoidin Domain Receptor 2 (DDR2) mediates Angiotensin II-dependent transcriptional upregulation of fibronectin by Yes-activated Protein in cardiac fibroblasts. Furthermore, siRNA-mediated fibronectin knockdown attenuated Angiotensin II-stimulated expression of collagen type I and anti-apoptotic cIAP2, and enhanced cardiac fibroblast susceptibility to apoptosis. Importantly, an obligate role for fibronectin was observed in Angiotensin II-stimulated expression of AT1R, the Angiotensin II receptor, which would link extracellular matrix (ECM) signaling and Angiotensin II signaling in cardiac fibroblasts. The role of fibronectin in Angiotensin II-stimulated cIAP2, collagen type I, and AT1R expression was mediated by Integrin-β1-integrin-linked kinase signaling. In vivo, we observed modestly reduced basal levels of AT1R in DDR2-null mouse myocardium, which were associated with the previously reported reduction in myocardial Integrin-β1 levels. The role of fibronectin, downstream of DDR2, could be a critical determinant of cardiac fibroblast-mediated wound healing following myocardial injury. In summary, our findings suggest a complex mechanism of regulation of cardiac fibroblast function involving two major ECM proteins, collagen type I and fibronectin, and their receptors, DDR2 and Integrin-β1.


Sign in / Sign up

Export Citation Format

Share Document