Higher growth rate and gene expression in male zebra finch embryos are independent of manipulation of maternal steroids in the eggs

2017 ◽  
Vol 254 ◽  
pp. 1-7
Author(s):  
Dorota Lutyk ◽  
Makhsud Tagirov ◽  
Szymon Drobniak ◽  
Joanna Rutkowska
1999 ◽  
Vol 19 (1) ◽  
pp. 899-908 ◽  
Author(s):  
Perry Kannan ◽  
Michael A. Tainsky

ABSTRACT ras oncogene-transformed PA-1 human teratocarcinoma cells have abundant AP-2 mRNA but, paradoxically, little AP-2 transcriptional activity. We have previously shown that overexpression of AP-2 in nontumorigenic variants of PA-1 cells results in inhibition of AP-2 activity and induction of tumorigenicity similar to that caused by ras transformation of PA-1 cells. Evidence indicated the existence of a novel mechanism of inhibition of AP-2 activity involving sequestering of transcriptional coactivators. In this study, we found that PC4 is a positive coactivator of AP-2 and can restore AP-2 activity in ras-transformed PA-1 cells. Relative to vector-transfected ras cell lines,ras cell lines stably transfected with and expressing the PC4 cDNA have a diminished growth rate and exhibit a loss of anchorage-independent growth, and they are unable to induce the formation of tumors in nude mice. These data suggest that a transcriptional coactivator, like a tumor suppressor, can have a growth-suppressive effect on cells. Our experiments are the first to show that ras oncogenes and oncogenic transcription factors can induce transformation through effects on the transcription machinery rather than through specific programs of gene expression.


2004 ◽  
Vol 70 (5) ◽  
pp. 2928-2934 ◽  
Author(s):  
Maria Lövenklev ◽  
Ingrid Artin ◽  
Oskar Hagberg ◽  
Elisabeth Borch ◽  
Elisabet Holst ◽  
...  

ABSTRACT The effects of carbon dioxide, sodium chloride, and sodium nitrite on type B botulinum neurotoxin (BoNT/B) gene (cntB) expression in nonproteolytic Clostridium botulinum were investigated in a tryptone-peptone-yeast extract (TPY) medium. Various concentrations of these selected food preservatives were studied by using a complete factorial design in order to quantitatively study interaction effects, as well as main effects, on the following responses: lag phase duration (LPD), growth rate, relative cntB expression, and extracellular BoNT/B production. Multiple linear regression was used to set up six statistical models to quantify and predict these responses. All combinations of NaCl and NaNO2 in the growth medium resulted in a prolonged lag phase duration and in a reduction in the specific growth rate. In contrast, the relative BoNT/B gene expression was unchanged, as determined by the cntB-specific quantitative reverse transcription-PCR method. This was confirmed when we measured the extracellular BoNT/B concentration by an enzyme-linked immunosorbent assay. CO2 was found to have a major effect on gene expression when the cntB mRNA levels were monitored in the mid-exponential, late exponential, and late stationary growth phases. The expression of cntB relative to the expression of the 16S rRNA gene was stimulated by an elevated CO2 concentration; the cntB mRNA level was fivefold greater in a 70% CO2 atmosphere than in a 10% CO2 atmosphere. These findings were also confirmed when we analyzed the extracellular BoNT/B concentration; we found that the concentrations were 27 ng · ml−1 · unit of optical density−1 in the 10% CO2 atmosphere and 126 ng · ml−1 · unit of optical density−1 in the 70% CO2 atmosphere.


2015 ◽  
Vol 17 (4) ◽  
pp. 785-790 ◽  
Author(s):  
Fuentes-Silva Carlos ◽  
G.M. Soto-Zarazúa ◽  
I. Torres-Pacheco ◽  
R.G. Guevara-González ◽  
J.F. García-Trejo ◽  
...  

Animals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2585
Author(s):  
Fang Jiang ◽  
Yan Lin ◽  
Linghong Miao ◽  
Jingyuan Hao

The ability of bamboo charcoal to reduce the negative effects of high dietary selenium (Se) concentrations was assessed by feeding juvenile blunt snout bream (Megalobrama amblycephala) one of five Se-rich diets (1.5 mg/kg Se; 36% protein, 8.7% lipid) containing graded levels (0–4 g/kg) of bamboo charcoal powder for eight weeks. There were four tanks (350 L) of fish (initial weight 16.0 ± 0.5 g) for each treatment, and the fish were fed to satiation four times each day. At the end of the feeding trial, all of the fish from each tank were weighed to calculate the growth performance. Blood samples were firstly obtained to collect plasma for the biochemical indexes determination. Liver tissues were then collected to determine the antioxidant enzyme activities and gene expression. Dorsal muscles were also collected to determine the nutrient composition. The results show that when the bamboo charcoal content in the Se-rich feed ranged between 0 and 3 g/kg, the weight growth rate (WGR) and specific growth rate (SGR) values increased with the higher dietary bamboo charcoal content, and the maximum WGR and SGR values were achieved when the bamboo charcoal content in the Se-rich feed was 2–3 g/kg (p < 0.05). The Se content in muscle tissues decreased significantly with the increased bamboo charcoal content (p < 0.05) in the Se-rich feed, which ranged from 0 to 4 g/kg. When the bamboo charcoal content in the Se-rich feed was 2–3 g/kg, the levels of glucose (GLU) and albumin (ALB) in plasma reached a maximum (p < 0.05), whereas the level of alkaline phosphatase (ALP) reached a minimum (p < 0.05). Additionally, the activities of catalase (CAT), total superoxide dismutase (T-SOD), total antioxidative capacity (T-AOC), and glutathione peroxidase (GSH-Px) were significantly enhanced (p < 0.05) when the bamboo charcoal content was 3 g/kg. In contrast, the malondialdehyde (MDA) level increased sharply when the bamboo charcoal content in the Se-rich feed was 1 g/kg, compared to the control group and the groups supplemented with 2–3 g/kg bamboo charcoal (p < 0.05). Regarding mRNA-level gene expression, the results show that dietary supplementation with 0 to 3 g/kg of bamboo charcoal increased the expression of keap1 and nrf2, whereas nfkb expression was inhibited (p < 0.05). The mRNA expression of the antioxidant enzymes cat, gpx, and mn-sod was consistently enhanced in the group fed with the 3 g/kg bamboo charcoal diet (p < 0.05). The expression of the pro-inflammatory cytokines tnfα and tgfβ was inhibited in the groups supplemented with 2–3 g/kg bamboo charcoal, whereas the expression of anti-inflammatory cytokines (il10) increased in the bamboo charcoal supplementation groups compared to the control group (p < 0.05). Generally, supplementation with 2–3 g/kg of bamboo charcoal in Se-rich feed improved the growth performance, physiological status, and antioxidant enzyme activities of blunt snout bream. Moreover, bamboo charcoal supplementation in Se-rich diets stimulated the antioxidant system and inhibited the inflammatory response by activating Nrf2-Keap1 and suppressing NF-κB.


2013 ◽  
Vol 46 (23) ◽  
pp. 271-276 ◽  
Author(s):  
Alfonso Carta ◽  
Madalena Chaves ◽  
Jean-Luc Gouzé

2015 ◽  
Vol 27 (1) ◽  
pp. 95
Author(s):  
G. Gamarra ◽  
C. Ponsart ◽  
S. Lacaze ◽  
F. Nuttinck ◽  
P. Mermillod ◽  
...  

Dietary supplementation with propylene glycol (PG) increases the rate of grade 1 embryos produced from feed restricted females (Gamarra et al. 2014 Reprod. Fertil. Dev.). The aim of this study was to evaluate if a PG feeding supplement could modify the expression profile of selected candidate genes that are important for in vitro embryo development and the gene expression patterns of the insulin-like growth factor (IGF) system in oocytes and cumulus cells in feed-restricted heifers. Feed-restricted heifers (n = 16, growth rate of 600 g day–1) received a single daily drench of 400 mL of water (group restricted, R) from Day 1 to Day 9 of a first synchronized oestrous cycle followed by 400 mL of PG from Day 1 to Day 9 of the second synchronized oestrous cycle (group restricted + PG, RPG). Ovum pick-up (OPU) was performed following superovulation, on Day 5 of the oestrous cycle to produce embryos in vitro and on Day 9 without superovulation to obtain oocytes and cumulus cells. The same protocol was used in control animals (n = 6, growth rate of 800 g day–1). Real-time PCR was used to determine the relative abundance of genes involved in lipid metabolism and storage (PLIN2, SCD), energy metabolism (ATP5A1, GLUT1), membrane permeability (AQP3), epigenetic marks (DNMT3a), apoptosis (BAX, TP53), and protein processing (HSPA9B) in grade 1 blastocysts, IGF1, IGF1R, IGFBP2, IGFBP4 in cumulus cells, and IGF1R and IGFBP2 in oocytes. Mann-Whitney nonparametric tests were performed to analyse gene expression results. The expression of PLIN2, ATP5A1, GLUT1, AQP3, DNMT3a, BAX, and HSPA9B were decreased in embryos collected from restricted compared with control animals. The expression levels of these genes were restored when females were supplemented with PG. The expression of TP53 and SCD were not affected. In cumulus cells, the expression levels of IGF1, IGF1R, and IGFBP4 were decreased in restricted compared with control animals. The expression levels of IGF1 and IGF1R were restored with PG supplementation. No differences were observed for the IGFBP2 gene. In the oocytes, no differences were observed for the expression levels of IGF1R and IGFBP2 genes. In conclusion, this work shows for the first time that feed restriction and dietary supplementation by PG in heifers produced changes in gene expression in blastocysts and modified the pattern of the IGF system in cumulus cells. These results suggest the existence of an epigenetic regulation induced by PG during follicular growth, which can regulate the level of gene expression up to the blastocyst stage. In general, PG supplementation of feed-restricted donors restored gene expression at the levels observed after normal feeding.


2005 ◽  
Vol 16 (5) ◽  
pp. 2503-2517 ◽  
Author(s):  
Matthew J. Brauer ◽  
Alok J. Saldanha ◽  
Kara Dolinski ◽  
David Botstein

We studied the physiological response to glucose limitation in batch and steady-state (chemostat) cultures of Saccharomyces cerevisiae by following global patterns of gene expression. Glucose-limited batch cultures of yeast go through two sequential exponential growth phases, beginning with a largely fermentative phase, followed by an essentially completely aerobic use of residual glucose and evolved ethanol. Judging from the patterns of gene expression, the state of the cells growing at steady state in glucose-limited chemostats corresponds most closely with the state of cells in batch cultures just before they undergo this “diauxic shift.” Essentially the same pattern was found between chemostats having a fivefold difference in steady-state growth rate (the lower rate approximating that of the second phase respiratory growth rate in batch cultures). Although in both cases the cells in the chemostat consumed most of the glucose, in neither case did they seem to be metabolizing it primarily through respiration. Although there was some indication of a modest oxidative stress response, the chemostat cultures did not exhibit the massive environmental stress response associated with starvation that also is observed, at least in part, during the diauxic shift in batch cultures. We conclude that despite the theoretical possibility of a switch to fully aerobic metabolism of glucose in the chemostat under conditions of glucose scarcity, homeostatic mechanisms are able to carry out metabolic adjustment as if fermentation of the glucose is the preferred option until the glucose is entirely depleted. These results suggest that some aspect of actual starvation, possibly a component of the stress response, may be required for triggering the metabolic remodeling associated with the diauxic shift.


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