scholarly journals Adult teleost heart expresses two distinct troponin C paralogs: cardiac TnC and a novel and teleost-specific ssTnC in a chamber- and temperature-dependent manner

2013 ◽  
Vol 45 (18) ◽  
pp. 866-875 ◽  
Author(s):  
Christine E. Genge ◽  
William S. Davidson ◽  
Glen F. Tibbits

The teleost-specific whole genome duplication created multiple copies of genes allowing for subfunctionalization of isoforms. In this study, we show that the teleost cardiac Ca2+-binding troponin C (TnC) is the product of two distinct genes: cardiac TnC (cTnC, TnnC1a) and a fish-specific slow skeletal TnC (ssTnC, TnnC1b). The ssTnC gene is novel to teleosts as mammals have a single gene commonly referred as cTnC but which is also expressed in slow skeletal muscle. In teleosts, the data strongly indicate that these are two TnC genes are different paralogs. Because we determined that ssTnC exists across many teleosts but not in basal ray-finned fish (e.g., bichir), we propose that these paralogs are the result of an ancestral tandem gene duplication persisting only in teleosts. Quantification of mRNA levels was used to demonstrate distinct expression localization patterns of the paralogs within the chambers of the heart. In the adult zebrafish acclimated at 28°C, ssTnC mRNA levels are twofold greater than cTnC mRNA levels in the atrium, whereas cTnC mRNA was almost exclusively expressed in the ventricle. Meanwhile, rainbow trout acclimated at 5°C showed cTnC mRNA levels in both chambers significantly greater than ssTnC. Distinct responses to temperature acclimation were also quantified in both adult zebrafish and rainbow trout, with mRNA in both chambers shifting to express higher levels of cTnC in 18°C acclimated zebrafish and 5°C acclimated trout. Possible subfunctionalization of TnC isoforms may provide insight into how teleosts achieve physiological versatility in chamber-specific contractile properties.

2020 ◽  
Vol 21 (21) ◽  
pp. 7986
Author(s):  
Zeeshan Nasim ◽  
Muhammad Fahim ◽  
Katarzyna Gawarecka ◽  
Hendry Susila ◽  
Suhyun Jin ◽  
...  

Nonsense-mediated mRNA decay (NMD) removes aberrant transcripts to avoid the accumulation of truncated proteins. NMD regulates nucleotide-binding, leucine-rich repeat (NLR) genes to prevent autoimmunity; however, the function of a large number of NLRs still remains poorly understood. Here, we show that three NLR genes (AT1G72910, AT1G72940, and ADR1-LIKE 2) are important for NMD-mediated regulation of defense signaling at lower temperatures. At 16 °C, the NMD-compromised up-frameshift protein1 (upf1) upf3 mutants showed growth arrest that can be rescued by the artificial miRNA-mediated knockdown of the three NLR genes. mRNA levels of these NLRs are induced by Pseudomonas syringae inoculation and exogenous SA treatment. Mutations in AT1G72910, AT1G72940, and ADR1-LIKE 2 genes resulted in increased susceptibility to Pseudomonas syringae, whereas their overexpression resulted in severely stunted growth, which was dependent on basal disease resistance genes. The NMD-deficient upf1 upf3 mutants accumulated higher levels of NMD signature-containing transcripts from these NLR genes at 16 °C. Furthermore, mRNA degradation kinetics showed that these NMD signature-containing transcripts were more stable in upf1 upf3 mutants. Based on these findings, we propose that AT1G72910, AT1G72940, and ADR1-LIKE 2 are directly regulated by NMD in a temperature-dependent manner and play an important role in modulating plant immunity at lower temperatures.


1993 ◽  
Vol 70 (05) ◽  
pp. 800-806 ◽  
Author(s):  
C Ternisien ◽  
M Ramani ◽  
V Ollivier ◽  
F Khechai ◽  
T Vu ◽  
...  

SummaryTissue factor (TF) is a transmembrane receptor which, in association with factors VII and Vila, activates factor IX and X, thereby activating the coagulation protease cascades. In response to bacterial lipopolysaccharide (LPS) monocytes transcribe, synthesize and express TF on their surface. We investigated whether LPS-induced TF in human monocytes is mediated by protein kinase C (PKC) activation. The PKC agonists phorbol 12- myristate 13-acetate (PMA) and phorbol 12, 13 dibutyrate (PdBu) were both potent inducers of TF in human monocytes, whereas 4 alpha-12, 13 didecanoate (4 a-Pdd) had no such effect. Both LPS- and PMA-induced TF activity were inhibited, in a concentration dependent manner, by three different PKC inhibitors: H7, staurosporine and calphostin C. TF antigen determination confirmed that LPS-induced cell-surface TF protein levels decreased in parallel to TF functional activity under staurosporine treatment. Moreover, Northern blot analysis of total RNA from LPS- or PMA-stimulated monocytes showed a concentration-dependent decrease in TF mRNA levels in response to H7 and staurosporine. The decay rate of LPS-induced TF mRNA evaluated after the arrest of transcription by actinomycin D was not affected by the addition of staurosporine, suggesting that its inhibitory effect occurred at a transcriptional level. We conclude that LPS-induced production of TF and its mRNA by human monocytes are dependent on PKC activation.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 555d-555
Author(s):  
J.L. Olsen ◽  
S.A. Mehlenbacher ◽  
A.N. Azarenko

Hazelnuts are wind-pollinated, monoecious, mostly dichogamous, and self-incompatible of the sporophytic type. About 90% of the cultivars studied are protandrous. Anthesis of the pistillate flower is temperature-dependent and occurs from December through February, with its peak in January. Stigmatic surfaces may remain receptive for up to 3 months. Four to 5 months separate pollination and fertilization of the ovule, which usually occurs between mid-May and the end of June in Oregon. A 10% pollinizer density has been the standard, with a recommended distance of <20 m between the main cultivar and the nearest pollinizer. Two or three different pollinizer varieties with different times of pollen shed are recommended. The Oregon hazelnut industry is presently combating the fungal disease, Eastern Filbert Blight, Anisogramma anomala. Part of the current management recommendations are to reduce the susceptible pollinizer varieties to a density of around 5%, and then gradually replace those left with immune or more-resistant genotypes. Recent research by S.A. Mehlenbacher refined methods of using fluorescense microscopy to quickly determine genotype compatibility. The self-incompatiblity is controlled by a single gene with multiple alleles. The biochemical, physiological, and molecular aspects of sporophytic self-incompatiblity are being research by A.N. Azarenko.


2019 ◽  
Vol 18 (4) ◽  
pp. 334-341 ◽  
Author(s):  
Kun Fu ◽  
Liqiang Chen ◽  
Lifeng Miao ◽  
Yan Guo ◽  
Wei Zhang ◽  
...  

Background/Objective: Grape seed proanthocyanidins (GSPs) are a group of polyphenolic bioflavonoids, which possess a variety of biological functions and pharmacological properties. We studied the neuroprotective effects of GSP against oxygen-glucose deprivation/reoxygenation (OGD/R) injury and the potential mechanisms in mouse neuroblastoma N2a cells. Methods: OGD/R was conducted in N2a cells. Cell viability was evaluated by CCK-8 and LDH release assay. Apoptosis was assessed by TUNEL staining and flow cytometry. Protein levels of cleaved caspase-3, Bax and Bcl-2 were detected by Western blotting. CHOP, GRP78 and caspase-12 mRNA levels were assessed by real-time PCR. JC-1 dying was used to detect mitochondrial membrane potential. ROS levels, activities of endogenous antioxidant enzymes and ATP production were examined to evaluate mitochondrial function. Results: GSP increased cell viability after OGD/R injury in a dose-dependent manner. Furthermore, GSP inhibited cell apoptosis, reduced the mRNA levels of CHOP, GRP78 and caspase-12 (ER stressassociated genes), restored mitochondrial membrane potential and ATP generation, improved activities of endogenous anti-oxidant ability (T-AOC, GXH-Px, and SOD), and decreased ROS level. Conclusion: Our findings suggest that GSP can protect N2a cells from OGD/R insult. The mechanism of anti-apoptotic effects of GSP may involve attenuating ER stress and mitochondrial dysfunction.


2021 ◽  
Vol 9 (1) ◽  
pp. e001905
Author(s):  
Jung-Hee Hong ◽  
Dae-Hee Kim ◽  
Moon-Kyu Lee

IntroductionThe concept of glucolipotoxicity refers to the combined, deleterious effects of elevated glucose and/or fatty acid levels.Research design and methodsTo investigate the effects of chronic glucolipotoxicity on glucagon-like peptide-1-(7-36) amide (GLP-1) secretion, we generated glucolipotoxic conditions in human NCI-H716 enteroendocrine cells using either 5 or 25 mM glucose with or without 500 µM palmitate for 72 hours. For in vivo study, we have established a chronic nutrient infusion model in the rat. Serial blood samples were collected for 2 hours after the consumption of a mixed meal to evaluate insulin sensitivity and β-cell function.ResultsChronic glucolipotoxic conditions decreased GLP-1 secretion and the expressions of pCREB, pGSK3β, β-catenin, and TCF7L2 in NCI-H716 cells. Glucolipotoxicity conditions reduced glucose transporter expression, glucose uptake, and nicotinamide-adenine dinucleotide phosphate (NADPH) levels in L-cells, and increased triglyceride accumulation. In contrast, PPARα and ATP levels were reduced, which correlated well with decreased levels of SUR1 and Kir6.2, cAMP contents and expressions of pCAMK2, EPAC and PKA. We also observed an increase in reactive oxygen species production, UCP2 expression and Complex I activity. Simultaneous treatment with insulin restored the GLP-1 secretion. Glucolipotoxic conditions decreased insulin secretion in a time-dependent manner in INS-1 cells, which was recovered with exendin-4 cotreatment. Glucose and SMOFlipid infusion for 6 hours decreased GLP-1 secretion and proglucagon mRNA levels as well as impaired the glucose tolerance, insulin and C-peptide secretion in rats.ConclusionThese results provide evidence for the first time that glucolipotoxicity could affect GLP-1 secretion through changes in glucose and lipid metabolism, gene expressions, and proglucagon biosynthesis and suggest the interrelationship between glucolipotoxicities of L-cells and β-cells which develops earlier than that of L-cells.


Biomedicines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 861
Author(s):  
James Hentig ◽  
Kaylee Cloghessy ◽  
Manuela Lahne ◽  
Yoo Jin Jung ◽  
Rebecca A. Petersen ◽  
...  

Blunt-force traumatic brain injury (TBI) affects an increasing number of people worldwide as the range of injury severity and heterogeneity of injury pathologies have been recognized. Most current damage models utilize non-regenerative organisms, less common TBI mechanisms (penetrating, chemical, blast), and are limited in scalability of injury severity. We describe a scalable blunt-force TBI model that exhibits a wide range of human clinical pathologies and allows for the study of both injury pathology/progression and mechanisms of regenerative recovery. We modified the Marmarou weight drop model for adult zebrafish, which delivers a scalable injury spanning mild, moderate, and severe phenotypes. Following injury, zebrafish display a wide range of severity-dependent, injury-induced pathologies, including seizures, blood–brain barrier disruption, neuroinflammation, edema, vascular injury, decreased recovery rate, neuronal cell death, sensorimotor difficulties, and cognitive deficits. Injury-induced pathologies rapidly dissipate 4–7 days post-injury as robust cell proliferation is observed across the neuroaxis. In the cerebellum, proliferating nestin:GFP-positive cells originated from the cerebellar crest by 60 h post-injury, which then infiltrated into the granule cell layer and differentiated into neurons. Shh pathway genes increased in expression shortly following injury. Injection of the Shh agonist purmorphamine in undamaged fish induced a significant proliferative response, while the proliferative response was inhibited in injured fish treated with cyclopamine, a Shh antagonist. Collectively, these data demonstrate that a scalable blunt-force TBI to adult zebrafish results in many pathologies similar to human TBI, followed by recovery, and neuronal regeneration in a Shh-dependent manner.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lizhen Liu ◽  
Kaimin Hu ◽  
Jingjing Feng ◽  
Huafang Wang ◽  
Shan Fu ◽  
...  

Abstract Background Isocitrate dehydrogenase (IDH1/2) gene mutations are the most frequently observed mutations in cartilaginous tumors. The mutant IDH causes elevation in the levels of R-enantiomer of 2-hydroxylglutarate (R-2HG). Mesenchymal stromal cells (MSCs) are reasonable precursor cell candidates of cartilaginous tumors. This study aimed to investigate the effect of oncometabolite R-2HG on MSCs. Methods Human bone marrow MSCs treated with or without R-2HG at concentrations 0.1 to 1.5 mM were used for experiments. Cell Counting Kit-8 was used to detect the proliferation of MSCs. To determine the effects of R-2HG on MSC differentiation, cells were cultured in osteogenic, chondrogenic and adipogenic medium. Specific staining approaches were performed and differentiation-related genes were quantified. Furthermore, DNA methylation status was explored by Illumina array-based arrays. Real-time PCR was applied to examine the signaling component mRNAs involved in. Results R-2HG showed no influence on the proliferation of human MSCs. R-2HG blocked osteogenic differentiation, whereas promoted adipogenic differentiation of MSCs in a dose-dependent manner. R-2HG inhibited chondrogenic differentiation of MSCs, but increased the expression of genes related to chondrocyte hypertrophy in a lower concentration (1.0 mM). Moreover, R-2HG induced a pronounced DNA hypermethylation state of MSC. R-2HG also improved promotor methylation of lineage-specific genes during osteogenic and chondrogenic differentiation. In addition, R-2HG induced hypermethylation and decreased the mRNA levels of SHH, GLI1and GLI2, indicating Sonic Hedgehog (Shh) signaling inhibition. Conclusions The oncometabolite R-2HG dysregulated the chondrogenic and osteogenic differentiation of MSCs possibly via induction of DNA hypermethylation, improving the role of R-2HG in cartilaginous tumor development.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Tuo Deng ◽  
Wenwen Zhang ◽  
Yanling Zhang ◽  
Mengqi Zhang ◽  
Zhikun Huan ◽  
...  

Abstract Background As the incidence of secretory osteoporosis has increased, bone loss, osteoporosis and their relationships with thyroid-stimulating hormone (TSH) have received increased attention. In this study, the role of TSH in bone metabolism and its possible underlying mechanisms were investigated. Methods We analyzed the serum levels of free triiodothyronine (FT3), free thyroxine (FT4), and TSH and the bone mineral density (BMD) levels of 114 men with normal thyroid function. In addition, osteoblasts from rat calvarial samples were treated with different doses of TSH for different lengths of time. The related gene and protein expression levels were investigated. Results A comparison of the BMD between the high-level and low-level serum TSH groups showed that the TSH serum concentration was positively correlated with BMD. TSH at concentrations of 10 mU/mL and 100 mU/mL significantly increased the mRNA levels of ALP, COI1 and Runx2 compared with those of the control (P < 0.05, P < 0.01). Bone morphogenetic protein (BMP)2 activity was enhanced with both increased TSH concentration and increased time. The protein levels of Runx2 and osterix were increased in a dose-dependent manner. Conclusions The circulating concentrations of TSH and BMD were positively correlated with normal thyroid function in males. TSH promoted osteoblast proliferation and differentiation in rat primary osteoblasts.


1994 ◽  
Vol 267 (3) ◽  
pp. G380-G386 ◽  
Author(s):  
C. M. Rabergh ◽  
K. Ziegler ◽  
B. Isomaa ◽  
M. M. Lipsky ◽  
J. E. Eriksson

The uptake of the bile acids cholate (CHA) and taurocholate (TCHA) was studied in isolated hepatocytes from rainbow trout (Oncorhynchus mykiss). Both CHA and TCHA were taken up in a concentration- and temperature-dependent manner with optimum temperature at 15 degrees C and a strikingly efficient uptake even at low temperatures (0-5 degrees C). The total uptake was a combination of a saturable [Michaelis-Menten constant (Km) for CHA, 20 microM; Km for TCHA, 19 microM] and a nonsaturable component. The maximal uptake rate of the saturable component was 416 and 805 pmol.mg protein-1.min-1 for CHA and TCHA, respectively. The uptake of both bile acids was shown to be energy dependent, since it was inhibited by the metabolic inhibitors antimycin A, oligomycin and carbonyl cyanide m-chlorophenylhydrazone. The uptake was clearly Na+ independent, since isosmotic replacement of extracellular Na+ by Li+, choline, or K+ did not inhibit the uptake. Furthermore, it seemed to be independent of the presence of extracellular Cl-, since it was not inhibited by replacement of Cl- with sodium gluconate. On the whole, our results show that the hepatocellular uptake of bile acids in rainbow trout is mediated by a Na(+)-independent carrier system, with characteristics resembling the corresponding transport component in mammalian hepatocytes, but with high efficiency even at low temperatures.


Endocrinology ◽  
2004 ◽  
Vol 145 (12) ◽  
pp. 5525-5531 ◽  
Author(s):  
Gary M. Leong ◽  
Sofia Moverare ◽  
Jesena Brce ◽  
Nathan Doyle ◽  
Klara Sjögren ◽  
...  

Abstract Suppressors of cytokine signaling (SOCS) are important negative regulators of cytokine action. We recently reported that estrogen stimulates SOCS-2 expression and inhibits GH signaling in kidney cells. The effects of estrogen on SOCS expression in other tissues are unclear. The aim of this study was to investigate in vivo and in vitro whether estrogen affected SOCS expression in the liver, a major target organ of GH. The in vivo hepatic effects of estrogen on ovariectomized mice lacking estrogen receptor (ER)-α, ERβ, or both and their wild-type littermates were examined by DNA microarray analysis. In vitro, the effects of estrogen on SOCS expression in human hepatoma cells were examined by reverse transcription quantitative PCR. Long-term (3 wk) estrogen treatment induced a 2- to 3-fold increase in hepatic expression of SOCS-2 and -3 in wild-type and ERβ knockout mice but not in those lacking ERα or both ER subtypes. Short-term treatment (at 24 h) increased the mRNA level of SOCS-3 but not SOCS-2. In cultured hepatoma cells, estrogen increased SOCS-2 and -3 mRNA levels by 2-fold in a time- and dose-dependent manner (P &lt; 0.05). Estrogen induced murine SOCS-3 promoter activity by 2-fold (P &lt; 0.05) in constructs containing a region between nucleotides −1862 and −855. Moreover, estrogen and GH had additive effects on the SOCS-3 promoter activity. In summary, estrogen, via ERα, up-regulated hepatic expression of SOCS-2 and -3, probably through transcriptional activation. This indicates a novel mechanism of estrogen regulation of cytokine action.


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