scholarly journals Cardiac fibroblasts require focal adhesion kinase for normal proliferation and migration

2009 ◽  
Vol 296 (3) ◽  
pp. H627-H638 ◽  
Author(s):  
Ana Maria Manso ◽  
Seok-Min Kang ◽  
Sergey V. Plotnikov ◽  
Ingo Thievessen ◽  
Jaewon Oh ◽  
...  
Keyword(s):  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Adult Mouse ◽  
Cardiac Fibroblasts ◽  
Focal Adhesions ◽  
Protein Levels ◽  
Tyrosine Kinase 2 ◽  
A Cell ◽  
And Migration ◽  
Proliferation And Migration

Migration and proliferation of cardiac fibroblasts (CFs) play an important role in the myocardial remodeling process. While many factors have been identified that regulate CF growth and migration, less is known about the signaling mechanisms involved in these processes. Here, we utilized Cre-LoxP technology to obtain focal adhesion kinase (FAK)-deficient adult mouse CFs and studied how FAK functioned in modulating cell adhesion, proliferation, and migration of these cells. Treatment of FAKflox/flox CFs with Ad/Cre virus caused over 70% reduction of FAK protein levels within a cell population. FAK-deficient CFs showed no changes in focal adhesions, cell morphology, or protein expression levels of vinculin, talin, or paxillin; proline-rich tyrosine kinase 2 (Pyk2) expression and activity were increased. Knockdown of FAK protein in CFs increased PDGF-BB-induced proliferation, while it reduced PDGF-BB-induced migration. Adhesion to fibronectin was not altered. To distinguish between the function of FAK and Pyk2, FAK function was inhibited via adenoviral-mediated overexpression of the natural FAK inhibitor FAK-related nonkinase (FRNK). Ad/FRNK had no effect on Pyk2 expression, inhibited the PDGF-BB-induced migration, but did not change the PDGF-BB-induced proliferation. FAK deficiency had only modest effects on increasing PDGF-BB activation of p38 and JNK MAPKs, with no alteration in the ERK response vs. control cells. These results demonstrate that FAK is required for the PDGF-BB-induced migratory response of adult mouse CFs and suggest that FAK could play an essential role in the wound-healing response that occurs in numerous cardiac pathologies.

scholarly journals Focal adhesion kinase signaling is decreased in polyamine-depleted IEC-6 cells

2001 ◽  
Vol 281 (2) ◽  
pp. C475-C485 ◽  
Author(s):  
Ramesh M. Ray ◽  
Mary Jane Viar ◽  
Shirley A. McCormack ◽  
Leonard R. Johnson
Keyword(s):  
Extracellular Matrix ◽  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Focal Adhesions ◽  
Stress Fiber ◽  
Fiber Formation ◽  
Integrin Signaling ◽  
Actin Stress Fiber ◽  
Stress Fiber Formation ◽  
And Migration

Polyamines are essential to the migration of epithelial cells in the intestinal mucosa. Cells depleted of polyamines do not attach as rapidly to the extracellular matrix and do not form the actin stress fibers essential for migration. Because both attachment and stress fiber formation depend on integrin signaling and the formation of focal adhesions, we examined these and related processes in polyamine-depleted IEC-6 cells. There was general decreased tyrosine phosphorylation of focal adhesion kinase (FAK), and, specifically, decreased phosphorylation of Tyr-925, the paxillin binding site. In control cells, FAK phosphorylation was rapid after attachment to the extracellular matrix, while attached cells depleted of polyamines had significantly delayed phosphorylation. FAK activity was also significantly inhibited in polyamine-depleted cells as was the phosphorylation of paxillin. Polyamine-depleted cells failed to spread normally after attachment, and immunocytochemistry showed little colocalization of FAK and actin compared with controls. Focal adhesion complex formation was greatly reduced in the absence of polyamines. These data suggest that defective integrin signaling may, at least in part, account for the decreased rates of attachment, actin stress fiber formation, spreading, and migration observed in polyamine-depleted cells.

Expression and characterization of splice variants of PYK2, a focal adhesion kinase-related protein

1998 ◽  
Vol 111 (14) ◽  
pp. 1981-1991 ◽  
Author(s):  
W.C. Xiong ◽  
M. Macklem ◽  
J.T. Parsons
Keyword(s):  
Tyrosine Kinase ◽  
Focal Adhesion Kinase ◽  
Rat Brain ◽  
Functional Diversity ◽  
Focal Adhesion ◽  
Focal Adhesions ◽  
Receptor Protein ◽  
Protein Tyrosine ◽  
Terminal Domain ◽  
Tyrosine Kinase 2

Focal adhesion kinase and the recently identified proline-rich tyrosine kinase 2 (PYK2), also known as cell adhesion kinase β, related adhesion focal tyrosine kinase or calcium-dependent protein tyrosine kinase, define a new family of non-receptor protein tyrosine kinases. Activation of PYK2 has been implicated in multiple signaling events, including modulation of ion channels, T- and B-cell receptor signaling and cell death. Mechanisms underlying the functional diversity of PYK2 are unclear. Here, we provide evidence for two novel alternatively expressed isoforms of PYK2. One isoform, designated PYK2s (PYK2 splice form), appears to be a splice variant of PYK2 lacking 42 amino acids within the C-terminal domain. A second isoform, referred to as PRNK (PYK2-related non-kinase), appears to be specified by mRNAs that encode only part of the C-terminal domain of PYK2. Northern blot analysis indicates that the unspliced PYK2 is expressed at high levels in the brain and poorly expressed in the spleen, whereas PYK2s and PRNK are expressed in the spleen. In situ hybridization studies of rat brain demonstrate that the unspliced PYK2 is selectively expressed at high levels in hippocampus, cerebral cortex and olfactory bulb, whereas PYK2s and PRNK are expressed at low levels in all regions of rat brain examined. Immunofluorescence analysis of ectopically expressed PRNK protein shows that PRNK, in contrast to full-length PYK2, is localized to focal adhesions by sequences within the focal adhesion targeting domain. In addition, PYK2, but not PRNK, interacts with p130(cas)and Graf. These results imply that PRNK may selectively regulate PYK2 function in certain cells by binding to some but not all PYK2 binding partners, and the functional diversity mediated by PYK2 may be due in part to complex alternative splicing.

scholarly journals Glycogen synthase kinase 3β promotes osteosarcoma invasion and migration via regulating PTEN and phosphorylation of focal adhesion kinase

2021 ◽  
Author(s):  
Wei Mai ◽  
Lingyu Kong ◽  
Hongwei Yu ◽  
Junjie Bao ◽  
Chunyu Song ◽  
...  
Keyword(s):  
Focal Adhesion Kinase ◽  
Western Blotting ◽  
Focal Adhesion ◽  
Glycogen Synthase ◽  
Migration And Invasion ◽  
Glycogen Synthase Kinase 3Β ◽  
Sirna Transfection ◽  
Invasion And Migration ◽  
Human Osteosarcoma ◽  
And Migration

Aim: Typical features of human osteosarcoma are highly invasive and migratory capacities. Our study aimed to investigate the roles of glycogen synthase kinase 3β (GSK3β) in human osteosarcoma metastasis. Methods: GSK3β expressions in clinical osteosarcoma tissues with or without metastasis were examined by immunohistochemical staining. The expressions of GSK3β, p-GSK3βSer9, and p-GSK3βTyr216 in human osteoblast cells (hFOB1.19) and human osteosarcoma cells (MG63, SaOS-2 and U2-OS) were detected by western blotting. The GSK3β activity was measured by non-radio isotopic in vitro kinase assay. Migration and invasion abilities of MG-63 cells treated with small-molecular GSK3β inhibitors were respectively examined by monolayer-based wound-healing assay and transwell assay. The mRNA expressions of GSK3β, matrix metalloproteinase-2 (MMP-2), MMP-9, phosphatase with tensin homology (PTEN), and focal adhesion kinase (FAK) were detected after siRNA transfection for 72 h. Meanwhile, protein expressions of GSK3β, FAK, p-FAKY397, PTEN, MMP-2, and MMP-9 were measured by western blotting. Results: Clinical osteosarcoma tissues with metastasis showed higher GSK3β expressions. MG63 and U2-OS cells which were easy to occur metastasis showed significantly higher expressions and activities of GSK3β than SaOS-2 cells. Inhibition of GSK3β with small-molecular GSK3β inhibitors in MG63 cells significantly attenuated cell migration and invasion. These effects were associated with reduced expressions of MMP-2 and MMP-9. Moreover, increased PTEN and decreased p-FAKY397 expressions were observed following GSK3b knock-down by siRNA transfection. Conclusion: GSK3β might promote osteosarcoma invasion and migration via pathways associated with PTEN and phosphorylation of FAK.

scholarly journals hTERT Promotes CRC Proliferation and Migration by Recruiting YBX1 to Increase NRF2 Expression

2021 ◽  
Vol 9 ◽  
Author(s):  
Chunli Gong ◽  
Huan Yang ◽  
Sumin Wang ◽  
Jiao Liu ◽  
Zhibin Li ◽  
...  
Keyword(s):  
Cancer Progression ◽  
Promoter Activity ◽  
Related Factor ◽  
Human Telomerase Reverse Transcriptase ◽  
Protein Levels ◽  
Cellular Reactive Oxygen Species ◽  
And Migration ◽  
Human Telomerase ◽  
Nrf2 Expression ◽  
Proliferation And Migration

High human telomerase reverse transcriptase (hTERT) expression is related to severe Colorectal Cancer (CRC) progression and negatively related to CRC patient survival. Previous studies have revealed that hTERT can reduce cancer cellular reactive oxygen species (ROS) levels and accelerate cancer progression; however, the mechanism remains poorly understood. NFE2-related factor 2 (NRF2) is a molecule that plays a significant role in regulating cellular ROS homeostasis, but whether there is a correlation between hTERT and NRF2 remains unclear. Here, we showed that hTERT increases CRC proliferation and migration by inducing NRF2 upregulation. We further found that hTERT increases NRF2 expression at both the mRNA and protein levels. Our data also revealed that hTERT primarily upregulates NRF2 by increasing NRF2 promoter activity rather than by regulating NRF2 mRNA or protein stability. Using DNA pull-down/MS analysis, we found that hTERT can recruit YBX1 to upregulate NRF2 promoter activity. We also found that hTERT/YBX1 may localize to the P2 region of the NRF2 promoter. Taken together, our results demonstrate that hTERT facilitates CRC proliferation and migration by upregulating NRF2 expression through the recruitment of the transcription factor YBX1 to activate the NRF2 promoter. These results provide a new theoretical basis for CRC treatment.

scholarly journals Characterization of the Roles of Vimentin in Regulating the Proliferation and Migration of HSCs during Hepatic Fibrogenesis

Cells ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1184 ◽  
Author(s):  
Pei-Wen Wang ◽  
Tung-Ho Wu ◽  
Tung-Yi Lin ◽  
Mu-Hong Chen ◽  
Chau-Ting Yeh ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Messenger Rna ◽  
Rho Gtpase ◽  
Focal Adhesions ◽  
Cytoskeletal Proteins ◽  
Nuclear Antigen ◽  
Dependent Manner ◽  
Hepatic Fibrogenesis ◽  
And Migration ◽  
Proliferation And Migration

The activation of hepatic stellate cells (HSCs) manifested as proliferation and migration is the pivotal event involved in liver fibrogenesis. The vimentin network, an intermediate filament (IF) system, is one of the critical cascades by which the cell morphology, growth, and motility are modulated. However, the vimentin-mediated cytoskeletal cross talk, as well as the signaling transduction, which further coordinates the cellular responses during hepatic fibrogenesis, is poorly understood. In the current study, both messenger RNA (mRNA) and the vimentin protein were significantly increased in a time-dependent manner in the dimethylnitrosamine (DMN)-exposed liver. In particular, vimentin was highly expressed in the activated HSCs. Again, the overexpressed vimentin was observed in the plasma samples derived from patients with hepatic fibrosis/cirrhosis, suggesting that vimentin may be a key factor in regulating the progression of liver fibrosis. Meanwhile, vimentin knockdown suppressed the migratory propensity, provoked morphological changes, and disturbed the focal adhesions in the HSCs due to the breakdown of associated cytoskeletal proteins. Western blotting showed that vimentin deletion inhibited proliferating cell nuclear antigen (PCNA) and arrested the Rho GTPase family, thereby impairing the HSCs’ growth as well as motility. The phosphorylated extracellular-signal regulated kinase (ERK) and AKT signals were also notably reduced in response to the silence of vimentin. Inhibitors of selected signaling pathways suppressed the migration and differentiation of activated HSCs by regulating specific serine phosphorylated sites on vimentin. Taken together, these findings revealed a novel mechanism of vimentin through which various signaling pathways controlled the proliferation, differentiation, and movement of the HSCs via the ERK/AKT and Rho cascades.

scholarly journals Contractility modulates cell adhesion strengthening through focal adhesion kinase and assembly of vinculin-containing focal adhesions

2010 ◽  
pp. n/a-n/a ◽  
Author(s):  
David W. Dumbauld ◽  
Heungsoo Shin ◽  
Nathan D. Gallant ◽  
Kristin E. Michael ◽  
Harish Radhakrishna ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Focal Adhesions
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