scholarly journals Binding of Delta1, Jagged1, and Jagged2 to Notch2 Rapidly Induces Cleavage, Nuclear Translocation, and Hyperphosphorylation of Notch2

2000 ◽  
Vol 20 (18) ◽  
pp. 6913-6922 ◽  
Author(s):  
Kiyoshi Shimizu ◽  
Shigeru Chiba ◽  
Noriko Hosoya ◽  
Keiki Kumano ◽  
Toshiki Saito ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Notch Signaling ◽  
Time Course ◽  
Nuclear Translocation ◽  
Reporter Genes ◽  
Time Dependent ◽  
Dependent Manner ◽  
Notch Receptors ◽  
Notch Protein ◽  
Membrane Spanning

ABSTRACT Delta1, Jagged1, and Jagged2, commonly designated Delta/Serrate/LAG-2 (DSL) proteins, are known to be ligands for Notch1. However, it has been less understood whether they are ligands for Notch receptors other than Notch1. Meanwhile, ligand-induced cleavage and nuclear translocation of the Notch protein are considered to be fundamental for Notch signaling, yet direct observation of the behavior of the Notch molecule after ligand binding, including cleavage and nuclear translocation, has been lacking. In this report, we investigated these issues for Notch2. All of the three DSL proteins bound to endogenous Notch2 on the surface of BaF3 cells, although characteristics of Jagged2 for binding to Notch2 apparently differed from that of Delta1 and Jagged1. After binding, the three DSL proteins induced cleavage of the membrane-spanning subunit of Notch2 (Notch2TM), which occurred within 15 min. In a simultaneous time course, the cleaved fragment of Notch2TMwas translocated into the nucleus. Interestingly, the cleaved Notch2 fragment was hyperphosphorylated also in a time-dependent manner. Finally, binding of DSL proteins to Notch2 also activated the transcription of reporter genes driven by the RBP-Jκ-responsive promoter. Together, these data indicate that all of these DSL proteins function as ligands for Notch2. Moreover, the findings of rapid cleavage, nuclear translocation, and phosphorylation of Notch2 after ligand binding facilitate the understanding of the Notch signaling.

14-Deoxy-11,12-Didehydroandrographolide Ameliorates Glucose Intolerance Enhancing the LKB1/AMPKα/TBC1D1/GLUT4 Signaling Pathway and Inducing GLUT4 Expression in Myotubes and Skeletal Muscle of Obese Mice

2021 ◽  
pp. 1-19
Author(s):  
Chih-Chieh Chen ◽  
Chong-Kuei Lii ◽  
Chia-Wen Lo ◽  
Yi-Hsueh Lin ◽  
Ya-Chen Yang ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Signaling Pathway ◽  
Nuclear Translocation ◽  
Time Dependent ◽  
Antidiabetic Activity ◽  
C2c12 Myotubes ◽  
Dependent Manner ◽  
Compound C

14-Deoxy-11,12-didehydroandrographolide (deAND), a bioactive component of Andrographis paniculata, has antidiabetic activity. AMP-activated protein kinase (AMPK) regulates glucose transport and ameliorates insulin resistance. The aim of the present study was to investigate whether activation of AMPK is involved in the mechanism by which deAND ameliorates insulin resistance in muscles. deAND amounts up to 40 [Formula: see text]M dose-dependently activated phosphorylation of AMPK[Formula: see text] and TBC1D1 in C2C12 myotubes. In addition, deAND significantly activated phosphorylation of LKB1 at 6 h after treatment, and this activation was maintained up to 48 h. deAND increased glucose uptake at 18 h after treatment, and this increase was time dependent up to 72 h. Compound C, an inhibitor of AMPK, suppressed deAND-induced phosphorylation of AMPK[Formula: see text] and TBC1D1 and reversed the effect on glucose uptake. In addition, the expression of GLUT4 mRNA and protein in C2C12 myotubes was up-regulated by deAND in a time-dependent manner. Promotion of GLUT4 gene transcription was verified by a pGL3-GLUT4 (837 bp) reporter assay. deAND also increased the nuclear translocation of MEF-2A and PPAR[Formula: see text]. After 16 weeks of feeding, the high-fat diet (HFD) inhibited phosphorylation of AMPK[Formula: see text] and TBC1D1 in skeletal muscle of obese C57BL/6JNarl mice, and deactivation of AMPK[Formula: see text] and TBC1D1 by the HFD was abolished by deAND supplementation. Supplementation with deAND significantly promoted membrane translocation of GLUT4 compared with the HFD group. Supplementation also significantly increased GLUT4 mRNA and protein expression in skeletal muscle compared with the HFD group. The hypoglycemic effects of deAND are likely associated with activation of the LKB1/AMPK[Formula: see text]/TBC1D1/GLUT4 signaling pathway and stimulation of MEF-2A- and PPAR[Formula: see text]-dependent GLUT4 gene expression, which account for the glucose uptake into skeletal muscle and lower blood glucose levels.

scholarly journals Post-translational alterations in newly synthesized cartilage proteoglycans induced by the glutamine analogue 6-diazo-5-oxo-l-norleucine. Time course of inhibition and recovery

1991 ◽  
Vol 273 (2) ◽  
pp. 283-288 ◽  
Author(s):  
C C Clark ◽  
C F Richards ◽  
R V Iozzo
Keyword(s):  
Time Course ◽  
Chondroitin Sulphate ◽  
Time Dependent ◽  
Dependent Manner ◽  
Cartilage Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan ◽  
Cartilage Proteoglycans ◽  
Matrix Free ◽  
Subsequent Addition

Incorporation of [35S]sulphate by cultures of matrix-free cells from chick embryo sterna in the presence of the glutamine analogue 6-diazo-5-oxo-L-norleucine (0.58 mM) was inhibited in a time-dependent manner to less than 15% of that in control cultures after 2 h. Characterization of the major cartilage proteoglycan synthesized under these conditions showed that it contained few, if any, normal-sized chondroitin sulphate chains and only about half of the normal complement of substituted serine residues. Subsequent addition of D-glucosamine hydrochloride (final concn. 2 mM) resulted in a time-dependent recovery of [35S]sulphate incorporation to 90% of control cultures after 2 h, but restored the chondroitin sulphate chains to normal size within 15 min. On the basis of these results, it is concluded that a 2 h preincubation is necessary to deplete the chondrocytes of the endogenous supply of UDP-N-acetyl-D-glucosamine required for optimal glycoconjugate synthesis, and that this situation results in the synthesis of a chondroitin sulphate proteoglycan with significantly altered properties, owing to the paucity of glycosaminoglycan chains; however, this condition is completely reversible if the D-glucosamine pool is repleted.

scholarly journals Synthesis of a truncated Mr 46,000 mannose 6-phosphate receptor that is secreted and retains ligand binding

1989 ◽  
Vol 260 (1) ◽  
pp. 201-206 ◽  
Author(s):  
M Wendland ◽  
A Hille ◽  
G Nagel ◽  
A Waheed ◽  
K von Figura ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Stop Codon ◽  
Integral Membrane Protein ◽  
Site Directed Mutagenesis ◽  
Dependent Manner ◽  
Truncated Receptor ◽  
Receptor Cdna ◽  
Mannose 6 Phosphate ◽  
Complex Forms ◽  
Membrane Spanning

The Mr 46,000 mannose 6-phosphate receptor is an integral membrane protein with its ligand-binding site in the ectoplasmic domain. By site-directed mutagenesis, a stop codon was introduced in the receptor cDNA at the border between the ectoplasmic and membrane-spanning domain. The truncated receptor was expressed in three different systems, Xenopus oocytes, COS cells and BHK-21 cells. In all three systems the truncated receptor behaved as a soluble protein. In oocytes only small amounts of the truncated receptor were secreted within 48 h after synthesis. Accumulation of endoglucosaminidase H-sensitive forms of the truncated receptor in oocytes suggested that exit from the endoplasmic reticulum was slowed down. In COS and BHK-21 cells, the truncated receptor was secreted and, as for wild-type receptor, most of the N-linked oligosaccharides were processed to complex forms. Both the intracellularly-retained (oocytes) and the secreted (COS and BHK-21 cells) truncated receptors bound to phosphomannan-Sepharose in a mannose-6-phosphate-dependent manner. Using chemical cross-linking, the truncated receptor was shown to be secreted as a homodimer.

scholarly journals Isocudraxanthone K Induces Growth Inhibition and Apoptosis in Oral Cancer Cells via Hypoxia Inducible Factor-1α

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Mee-Ran Shin ◽  
Hwa-Jeong Lee ◽  
Soo-Kyung Kang ◽  
Q-Schick Auh ◽  
Young-Man Lee ◽  
...  
Keyword(s):  
Oral Cancer ◽  
Nuclear Translocation ◽  
Hypoxia Inducible Factor ◽  
Signal Transduction Pathway ◽  
Annexin V ◽  
Time Dependent ◽  
Drug Candidate ◽  
Root Bark ◽  
Dependent Manner ◽  
Antitumor Effects

Isocudraxanthone K (IK) is a novel, natural compound from a methanol extract of the root bark ofCudrania tricuspidata. It has not been shown previously that IK possessed antitumor activity. We investigated the antitumor effects and molecular mechanism of IK and related signal transduction pathway(s) in oral squamous cell carcinoma cells (OSCCCs). The MTT assay revealed that IK had an antiproliferative effect on OSCCCs, in a dose- and time-dependent manner. IK induced apoptosis in OSCCCs, as identified by a cell-cycle analysis, annexin V-FITC and propidium iodide staining, and the nuclear morphology in cell death. IK caused time-dependent phosphorylation of Akt, p38, and ERK (extracellular signal-regulated kinase). In addition, IK increased the cytosolic to nuclear translocation of nuclear factor-κB (NF-κB) p65 and the degradation and phosphorylation of IκB-αin HN4 and HN12 cells. Furthermore, IK treatment downregulated hypoxia-inducible factor 1α(HIF-1α) and its target gene, vascular endothelial growth factor (VEGF). Cobalt chloride (CoCl2), a HIF-1αactivator, attenuated the IK-induced growth-inhibiting and apoptosis-inducing effects, and blocked IK-induced expression of apoptosis regulatory proteins, such as Bax, Bcl-2, caspase-3, caspase-8, and caspase-9, and cytochrome c. Collectively, these data provide the first evidence of antiproliferative and apoptosis-inducing effects of IK as a HIF-1αinhibitor and suggest it may be a drug candidate for chemotherapy against oral cancer.

Effect of external Ca2+ concentration on stretch-augmented natriuretic peptide secretion by rat atria

1991 ◽  
Vol 260 (4) ◽  
pp. C756-C762 ◽  
Author(s):  
E. Page ◽  
J. Upshaw-Earley ◽  
G. E. Goings ◽  
D. A. Hanck
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Natriuretic Peptide ◽  
Time Course ◽  
Rate Coefficient ◽  
Time Dependent ◽  
Dependent Manner ◽  
Dependent Inactivation ◽  
Long Time ◽  
Peptide Secretion

An in vitro noncontracting rat atrial preparation stretched at 37 degrees C by a distending pressure of 5.1 mmHg was used to examine effects of external Ca2+ concentration ([Ca2+]out, 0.05-3.0 mM) on secretion of immunoreactive atrial natriuretic peptide (ANP) in presence of saxitoxin (STX) and in presence or absence of ryanodine. Under these conditions, the time course of the amount (y) of ANP secreted per milligram dry atrium during 44 min could be approximated by a rate coefficient (k) according to the relation y = s[1 - e(-kt)], where s is the maximal amount secreted after a long time (t). Although k, the rate coefficient for stretch-augmented secretion, increased significantly as [Ca2+]out was raised, secretion inactivated progressively in a time- and [Ca2+]out-dependent manner. This time-dependent decrease was not prevented by ryanodine. We conclude that a component of ANP secreted by quiescent atria in vitro is positively modulated by [Ca2+]out and does not require ryanodine-sensitive Ca2+ release from sarcoplasmic reticulum. The [Ca2+]out-sensitive processes underlying time-dependent inactivation of secretion remain undetermined.

scholarly journals NOTCH3 signaling is essential for NF-κB activation in TLR-activated macrophages

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Susana López-López ◽  
Eva María Monsalve ◽  
María José Romero de Ávila ◽  
Julia González-Gómez ◽  
Natalia Hernández de León ◽  
...  
Keyword(s):  
Notch Signaling ◽  
Macrophage Activation ◽  
Notch Signaling Pathway ◽  
P38 Map Kinase ◽  
Notch Receptor ◽  
Dependent Manner ◽  
Activated Macrophages ◽  
Notch Receptors ◽  
Inflammatory Processes ◽  
Tlr4 Activation

Abstract Macrophage activation by Toll receptors is an essential event in the development of the response against pathogens. NOTCH signaling pathway is involved in the control of macrophage activation and the inflammatory processes. In this work, we have characterized NOTCH signaling in macrophages activated by Toll-like receptor (TLR) triggering and determined that DLL1 and DLL4 are the main ligands responsible for NOTCH signaling. We have identified ADAM10 as the main protease implicated in NOTCH processing and activation. We have also observed that furin, which processes NOTCH receptors, is induced by TLR signaling in a NOTCH-dependent manner. NOTCH3 is the only NOTCH receptor expressed in resting macrophages. Its expression increased rapidly in the first hours after TLR4 activation, followed by a gradual decrease, which was coincident with an elevation of the expression of the other NOTCH receptors. All NOTCH1, 2 and 3 contribute to the increased NOTCH signaling detected in activated macrophages. We also observed a crosstalk between NOTCH3 and NOTCH1 during macrophage activation. Finally, our results highlight the relevance of NOTCH3 in the activation of NF-κB, increasing p65 phosphorylation by p38 MAP kinase. Our data identify, for the first time, NOTCH3 as a relevant player in the control of inflammation.

Abnormal 45Ca Fluxes in Dispersed Submandibular Acini of Rats Treated with Reserpine

1987 ◽  
Vol 66 (8) ◽  
pp. 1294-1299 ◽  
Author(s):  
R.M. Müller ◽  
J.R. Martinez
Keyword(s):  
Time Course ◽  
Chronic Treatment ◽  
Tracer Uptake ◽  
Time Dependent ◽  
Coupling Mechanism ◽  
Dependent Manner ◽  
Isotopic Tracer ◽  
Stimulus Response ◽  
Ca Uptake ◽  
Submandibular Acini

The uptake and efflux of the isotopic tracer 45Ca were compared in dispersed submandibular acini of both control rats and rats treated with seven daily doses of reserpine (0.5 mglkg, i.p.). Tracer uptake occurred in a time-dependent manner in both types of acini and reached 8.4 ± 0.2 and 8.0 ± 0.2 pmol/mg protein, respectively, in acini from control and treated animals after 60 min of incubation. Uptake of tracer was 2.35 nmol/mg DNA in control cells and 4 nmol/mg DNA in cells from treated rats at 60 min. 45Ca uptake (per mg protein) was enhanced in control acini 48% by 20 μmol/L epinephrine: 38% by 50 μmol/L carbachol; and 23% by 10 μmol/L isoproterenol. A similar order of potency was observed when uptake was expressed per mg DNA. In acini from reserpine-treated rats, 45Ca uptake (per mg protein) was increased 53% by epinephrine, 39% by isoproterenol, and only 8% by carbachol. The same enhanced effect of isoproterenol and lack of effect of carbachol were observed when uptake was calculated per mg DNA. In the absence of secretagogue, efflux of 45Ca from tracer-pre-loaded acini was larger in acini from reserpine-treated rats (53%) than in control acini (36%). Whether expressed in terms of mg protein or mg DNA, this efflux was increased in control acini 35% by epinephrine, from 25 to 28% by isoproterenol, and 17% by carbachol. In acini of reserpine-treated rats, epinephrine increased 45Ca efflux 20%, isoproterenol from 25 to 28%, and carbachol from 14 to 15%. The time course of epinephrine- and isoproterenol-induced efflux was also different from that in control cells. Thus, chronic treatment with reserpine altered uptake and efflux of 45Ca in rat submandibular acini. This suggests alterations in secretagogue-sensitive Ca++ pools or gating mechanisms and is likely to underlie disturbances in the Ca++-mediated events of the stimulus-response coupling mechanism, such as fluid, electrolyte, and protein secretion.

scholarly journals Temporal Splicing Switches in Elements of the TNF-Pathway Identified by Computational Analysis of Transcriptome Data for Human Cell Lines

2019 ◽  
Vol 20 (5) ◽  
pp. 1182 ◽  
Author(s):  
Nikolai Genov ◽  
Alireza Basti ◽  
Mónica Abreu ◽  
Angela Relógio
Keyword(s):  
Alternative Splicing ◽  
Cell Lines ◽  
Time Course ◽  
Stage Iv ◽  
Time Dependent ◽  
Aberrant Splice ◽  
Dependent Manner ◽  
Sequencing Data ◽  
Cellular Processes ◽  
Hodgkin Lymphoma Cell

Alternative splicing plays an important role in numerous cellular processes and aberrant splice decisions are associated with cancer. Although some studies point to a regulation of alternative splicing and its effector mechanisms in a time-dependent manner, the extent and consequences of such a regulation remains poorly understood. In the present work, we investigated the time-dependent production of isoforms in two Hodgkin lymphoma cell lines of different progression stages (HD-MY-Z, stage IIIb and L-1236, stage IV) compared to a B lymphoblastoid cell line (LCL-HO) with a focus on tumour necrosis factor (TNF) pathway-related elements. For this, we used newly generated time-course RNA-sequencing data from the mentioned cell lines and applied a computational pipeline to identify genes with isoform-switching behaviour in time. We analysed the temporal profiles of the identified events and evaluated in detail the potential functional implications of alterations in isoform expression for the selected top-switching genes. Our data indicate that elements within the TNF pathway undergo a time-dependent variation in isoform production with a putative impact on cell migration, proliferation and apoptosis. These include the genes TRAF1, TNFRSF12A and NFKB2. Our results point to a role of temporal alternative splicing in isoform production, which may alter the outcome of the TNF pathway and impact on tumorigenesis.

scholarly journals Autophagy Protects Renal Tubular Cells Against Ischemia / Reperfusion Injury in a Time-Dependent Manner

2015 ◽  
Vol 36 (1) ◽  
pp. 285-298 ◽  
Author(s):  
Xuejing Guan ◽  
Yingying Qian ◽  
Yue Shen ◽  
Lulu Zhang ◽  
Yi Du ◽  
...  
Keyword(s):  
Cell Apoptosis ◽  
Time Course ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Renal Ischemia ◽  
Time Dependent ◽  
Dependent Manner ◽  
Tubular Cells ◽  
Renal Tubular Cells ◽  
Renal Tubular

Background/Aims: Autophagy is a dynamic catabolic process that maintains cellular homeostasis. Whether it plays a role in promoting cell survival or cell death in the process of renal ischemia/reperfusion (I/R) remains controversial, partly because renal autophagy is usually examined at a certain time point. Therefore, monitoring of the whole time course of autophagy and apoptosis may help better understand the role of autophagy in renal I/R. Methods: Autophagy and apoptosis were detected after mice were subjected to bilateral renal ischemia followed by 0-h to 7-day reperfusion, exposure of TCMK-1 cells to 24-h hypoxia, and 2 to 24-h reoxygenation. The effect of autophagy on apoptosis was assessed in the presence of autophagy inhibitor 3-methyladenine (3-MA) and autophagy activator rapamycin. Results: Earlier than apoptosis, autophagy increased from 2-h reperfusion, reached the maximum at day 2, and then began declining from day 3 when renal damage had nearly recovered to normal. Exposure to 24-h hypoxia induced autophagy markedly, but it decreased drastically after 4 and 8-h reoxygenation, which was accompanied with increased cell apoptosis. Inhibition of autophagy with 3-MA increased the apoptosis of renal tubular cells during I/R in vivo and hypoxia/reoxygenation (H/R) in vitro. In contrast, activation of autophagy by rapamycin significantly alleviated renal tissue damage and tubular cell apoptosis in the two models. Conclusion: Autophagy was induced in a time-dependent manner and occurred earlier than the onset of cell apoptosis as an early response that played a renoprotective role during renal I/R and cell H/R. Up-regulation of autophagy may prove to be a potential strategy for the treatment of acute kidney injury.

Estrogen-induced upregulation of AR expression and enhancement of AR nuclear translocation in mouse fallopian tubes in vivo

2007 ◽  
Vol 292 (2) ◽  
pp. E604-E614 ◽  
Author(s):  
Ruijin Shao ◽  
Karin Ljungström ◽  
Birgitta Weijdegård ◽  
Emil Egecioglu ◽  
Julia Fernandez-Rodriguez ◽  
...  
Keyword(s):  
Fallopian Tube ◽  
Time Course ◽  
Nuclear Translocation ◽  
Immunohistochemical Analysis ◽  
Subsequent Treatment ◽  
Dependent Manner ◽  
Fallopian Tubes ◽  
Testosterone Levels ◽  
17Β Estradiol

Female mice lacking AR display alterations in ovarian and uterine function. However, the biology of AR in the fallopian tube is not fully understood. To gain an insight into potential roles of AR in this tissue, we demonstrated that eCG treatment increased AR expression in a time-dependent manner and subsequent treatment with hCG decreased AR expression in mouse fallopian tubes. This expression pattern was positively associated with 17β-estradiol and testosterone levels in vivo. Immunohistochemical analysis of fallopian tube epithelial cells revealed that nuclear localization of AR increased in parallel with decreased AR in the cytoplasm following eCG treatment. Moreover, we found that treatment with flutamide upregulated AR expression in immature mice in association with a decrease in serum testosterone levels, whereas the same treatment resulted in downregulation of AR expression in gonadotropin-stimulated mice with concomitant decreases in serum 17β-estradiol concentrations, suggesting that androgen differs from estrogen in the regulation of AR expression. Furthermore, we demonstrated that DES increased both AR protein expression and nuclear location over a 48-h time course. DHT had rapid effects, with induction of AR expression and translocation at 6 h after injection, but unlike DES it had prolonged efficacy. In addition, we provided direct in vivo evidence that nuclear protein interaction between AR and p21Cip1, a previously reported AR-regulated gene, was enhanced by gonadotropin stimulation. To our knowledge, this study provides the first demonstration to illustrate that estrogen as a principal regulator may contribute to regulate and activate AR in the fallopian tubes in vivo.

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