scholarly journals Complementary expression and phosphorylation of Cx46 and Cx50 during development and following gene deletion in mouse and in normal and orchitic mink testes

2015 ◽  
Vol 309 (3) ◽  
pp. R255-R276 ◽  
Author(s):  
R.-Marc Pelletier ◽  
Casimir D. Akpovi ◽  
Li Chen ◽  
Nalin M. Kumar ◽  
María L. Vitale
Keyword(s):  
Protein Expression ◽  
Germ Cell ◽  
Gap Junction ◽  
Sertoli Cell ◽  
Cell Communication ◽  
Seminiferous Tubules ◽  
Junction Protein ◽  
Mrna And Protein Expression ◽  
Autoimmune Orchitis ◽  
The Impact

Gap junction-mediated communication helps synchronize interconnected Sertoli cell activities. Besides, coordination of germ cell and Sertoli cell activities depends on gap junction-mediated Sertoli cell–germ cell communication. This report assesses mechanisms underlying the regulation of connexin 46 (Cx46) and Cx50 in mouse testis and those accompanying a “natural” seasonal and a pathological arrest of spermatogenesis, resulting from autoimmune orchitis (AIO) in mink. Furthermore, the impact of deleting Cx46 or Cx50 on the expression, phosphorylation of junction proteins, and spermatogenesis is evaluated. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. During the mink active spermatogenic phase, Cx50 became phosphorylated and localized to the site of the blood-testis barrier. By contrast, Cx46 was dephosphorylated and associated with annular junctions, suggesting phosphorylation/dephosphorylation of Cx46 and Cx50 involvement in the barrier dynamics. Cx46-positive annular junctions in contact with lipid droplets were found. Cx46 and Cx50 expression and localization were altered in mink with AIO. The deletion of Cx46 or Cx50 impacted on other connexin expression and phosphorylation and differently affected tight and adhering junction protein expression. The level of apoptosis, determined by ELISA, and a number of Apostain-labeled spermatocytes and spermatids/tubules were higher in mice lacking Cx46 ( Cx46−/−) than wild-type and Cx50−/− mice, arguing for life-sustaining Cx46 gap junction-mediated exchanges in late-stage germ cells secluded from the blood by the barrier. The data show that expression and phosphorylation of Cx46 and Cx50 are complementary in seminiferous tubules.

scholarly journals Ageratina adenophora Inhibits Spleen Immune Function in Rats via the Loss of the FRC Network and Th1–Th2 Cell Ratio Elevation

Toxins ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 309
Author(s):  
Zhihua Ren ◽  
Pei Gao ◽  
Samuel Kumi Okyere ◽  
Yujing Cui ◽  
Juan Wen ◽  
...  
Keyword(s):  
Protein Expression ◽  
Immune Function ◽  
Tissue Sample ◽  
Th2 Cells ◽  
Sample Collection ◽  
Functional Protein ◽  
Th2 Cell ◽  
Ageratina Adenophora ◽  
Mrna And Protein Expression ◽  
The Impact

The objective of this study was to determine the impact of Ageratina adenophora (A. adenophora) on splenic immune function in a rat model. Rats were fed with 10 g/100 g normal feed and an experimental feed, which was composed of 3:7 A. adenophora powder and normal feed for 60 days. On days 14, 28, and 60, subsets of rats (n = 8 rats/group/time point) were selected for blood and spleen tissue sample collection. The results showed that the proportion of CD3+ T cells in the spleen was decreased at day 60 (vs. control). Also, mRNA and protein expression of chemokines CCL21 and CCL19 and functional protein gp38 in spleen decreased significantly versus the control at day 60. In addition, ER-TR7 antigen protein expression was also decreased at day 60. Levels of T-helper (Th)1 cells significantly increased, whereas those of Th2 cells decreased significantly versus the control at day 60 in spleen. The finding revealed that A. adenophora could affect splenic immune function in rats by altering the fibroblast reticulocyte (FRC) network, as well as by causing an imbalance in Th1/Th2 cell ratios. This research provides new insights into potential mechanisms of spleen immunotoxicity due to exposures to A. Adenophora.

scholarly journals Connexin 43 Gap Junction Protein Expression during Follicular Development in the Porcine Ovary1

1998 ◽  
Vol 58 (2) ◽  
pp. 583-590 ◽  
Author(s):  
Judy A. Lenhart ◽  
Bruce R. Downey ◽  
Carol A. Bagnell
Keyword(s):  
Protein Expression ◽  
Gap Junction ◽  
Connexin 43 ◽  
Follicular Development ◽  
Junction Protein ◽  
Gap Junction Protein

Sertoli Cell-Germ Cell Communication

1989 ◽  
Vol 564 (1 Regulation of) ◽  
pp. 232-242 ◽  
Author(s):  
J. ANTON GROOTEGOED ◽  
PIET J. DEN BOER ◽  
PETRA MACKENBACH
Keyword(s):  
Germ Cell ◽  
Sertoli Cell ◽  
Cell Communication

Analysis of distribution patterns of gap junctions during development of embryonic chick facial primordia and brain

Development ◽  
1991 ◽  
Vol 111 (2) ◽  
pp. 509-522
Author(s):  
R. Minkoff ◽  
S.B. Parker ◽  
E.L. Hertzberg
Keyword(s):  
Gap Junctions ◽  
Gap Junction ◽  
Uniform Distribution ◽  
Rat Liver ◽  
Connexin 43 ◽  
Cell Communication ◽  
Exterior Surface ◽  
Junction Protein ◽  
Primary Palate ◽  
Gap Junction Protein

Gap junction distribution in the facial primordia of chick embryos at the time of primary palate formation was studied employing indirect immunofluorescence localization with antibodies to gap junction proteins initially identified in rat liver (27 × 10(3) Mr, connexin 32) and heart (43 × 10(3) Mr, connexin 43). Immunolocalization with antibodies to the rat liver gap junction protein (27 × 10(3) Mr) demonstrated a ubiquitous and uniform distribution in all regions of the epithelium and mesenchyme except the nasal placode. In the placodal epithelium, a unique non-random distribution was found characterized by two zones: a very heavy concentration of signal in the superficial layer of cells adjacent to the exterior surface and a region devoid of detectable signal in the interior cell layer adjacent to the mesenchyme. This pattern was seen during all stages of placode invagination that were examined. The separation of gap junctions in distinct cell layers was unique to the nasal placode, and was not found in any other region of the developing primary palate. One other tissue was found that exhibited this pattern-the developing neural epithelium of the brain and retina. These observations suggest the presence of region-specific signaling mechanisms and, possibly, an impedance of cell communication among subpopulations of cells in these structures at critical stages of development. Immunolocalization with antibodies to the ‘heart’ 43 × 10(3) Mr gap junction protein also revealed the presence of gap junction protein in facial primordia and neural epithelium. A non-uniform distribution of immunoreactivity was also observed for connexin 43.

Enhancement of liver cell gap junction protein expression by glucocorticoids

1994 ◽  
Vol 15 (9) ◽  
pp. 1807-1813 ◽  
Author(s):  
Ping Ren ◽  
Adriaan W. de Feijter ◽  
David L. Paul ◽  
Randall J. Ruch
Keyword(s):  
Protein Expression ◽  
Gap Junction ◽  
Liver Cell ◽  
Junction Protein ◽  
Gap Junction Protein

scholarly journals The impact of gap junction protein beta-2 (GJB2) heterozygosity on endometrial thickness, embryo transfer outcome and placentation

2018 ◽  
Vol 110 (4) ◽  
pp. e254
Author(s):  
L. Sekhon ◽  
Z. Luscher ◽  
S. Chang ◽  
J. Lee ◽  
L. Grunfeld ◽  
...  
Keyword(s):  
Gap Junction ◽  
Embryo Transfer ◽  
Endometrial Thickness ◽  
Junction Protein ◽  
Gap Junction Protein ◽  
Beta 2 ◽  
The Impact

scholarly journals ERK acts in parallel to PKCδ to mediate the connexin43-dependent potentiation of Runx2 activity by FGF2 in MC3T3 osteoblasts

2012 ◽  
Vol 302 (7) ◽  
pp. C1035-C1044 ◽  
Author(s):  
Corinne Niger ◽  
Atum M. Buo ◽  
Carla Hebert ◽  
Brian T. Duggan ◽  
Mark S. Williams ◽  
...  
Keyword(s):  
Gap Junction ◽  
Cell Communication ◽  
Transcriptional Response ◽  
Luciferase Reporter ◽  
Western Blots ◽  
Erk Activation ◽  
Junctional Communication ◽  
Junction Protein ◽  
Reporter Assays ◽  
Cell Cell

The gap junction protein, connexin43 (Cx43), plays an important role in skeletal biology. Previously, we have shown that Cx43 can enhance the signaling and transcriptional response to fibroblast growth factor 2 (FGF2) in osteoblasts by increasing protein kinase C-δ (PKCδ) activation to affect Runx2 activity. In the present study, we show by luciferase reporter assays that the ERK signaling cascade acts in parallel to PKCδ to modulate Runx2 activity downstream of the Cx43-dependent amplification of FGF2 signaling. The PKCδ-independent activation of ERK by FGF2 was confirmed by Western blotting, as was the Cx43-dependent enhancement of ERK activation. Consistent with our prior observations for PKCδ, flow cytometry analyses show that Cx43 overexpression enhances the percentage of phospho-ERK-positive cells in response to FGF2, supporting the notion that shared signals among gap junction-coupled cells result in the enhanced response to FGF2. Western blots and luciferase reporter assays performed on osteoblasts cultured under low-density and high-density conditions revealed that cell-cell contacts are required for Cx43 to amplify ERK activation and gene transcription. Similarly, inhibition of gap junctional communication with the channel blocker 18β-glycyrrhetinic acid attenuates the Cx43-dependent enhancement of Runx2-transcriptional activity. In total, these data underscore the importance of cell-cell communication and activation of the ERK and PKCδ pathways in the coordination of the osteoblast response to FGF2 among populations of osteoblasts.

Parathyroid hormone stimulates endothelial expression of atherosclerotic parameters through protein kinase pathways

2007 ◽  
Vol 292 (4) ◽  
pp. F1215-F1218 ◽  
Author(s):  
Gloria Rashid ◽  
Jacques Bernheim ◽  
Janice Green ◽  
Sydney Benchetrit
Keyword(s):  
Parathyroid Hormone ◽  
Protein Kinase ◽  
Protein Expression ◽  
Mrna Expression ◽  
Umbilical Vein ◽  
Protein Levels ◽  
Glycation End Products ◽  
Mrna And Protein Expression ◽  
Vascular Structures ◽  
The Impact

Parathyroid hormone (PTH), the major systemic calcium-regulating hormone, has been linked to uremic vascular changes. Considering the possible deleterious action of PTH on vascular structures, it seemed logical to evaluate the impact of PTH on the receptor of advanced glycation end products (RAGE) and interleukin 6 (IL-6) mRNA and protein expression, taking into account that such parameters might be involved in the pathogenesis of vascular calcification, atherosclerosis, and/or arteriolosclerosis. Human umbilical vein cord endothelial cells (HUVEC) were stimulated for 24 h with 10−12–10−10 mol/l PTH. The mRNA expression of RAGE and IL-6 was established by reverse transcriptase/PCR techniques. RAGE protein levels were determined by Western blot and IL-6 secretion was measured by ELISA. The pathways by which PTH may have an effect on HUVEC functions were evaluated. PTH (10−11–10−10mol/l) significantly increased RAGE mRNA and protein expression. PTH also significantly increased IL-6 mRNA expression without changes at protein levels. The addition of protein kinase (PKC or PKA) inhibitors or nitric oxide (NO) synthase inhibitors significantly reduced the RAGE and IL-6 mRNA expression and the RAGE protein expression. PTH stimulates the mRNA expressions of RAGE and IL-6 and the protein expression of RAGE. These stimulatory effects are probably through PKC and PKA pathways and are also NO dependent. Such data may explain the possible impact of PTH on the atherosclerotic and arteriosclerotic progression.

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