scholarly journals Vernalization-triggered expression of the antisense transcript COOLAIR is mediated by CBF genes

2021 ◽  
Author(s):  
Myeongjune Jeon ◽  
Goowon Jeong ◽  
Youbong Hyun ◽  
Ilha Lee

Many plants undergo vernalization, a long-term winter-triggered acceleration of flowering, to align their flowering time with spring. In Arabidopsis thaliana, this is achieved by silencing a floral repressor, FLOWERING LOCUS C (FLC). COOLAIR, an antisense noncoding RNA expressed at the FLC locus, is induced during the early phase of vernalization, preceding FLC suppression. However, the mechanism by which long-term cold induces COOLAIR is not well understood. Here, we showed that C-repeat (CRT)/dehydration-responsive elements (DREs) at the 3′-end of FLC and CRT/DRE-binding factors (CBFs) are required for vernalization-induced COOLAIR activation. The CBFs bind to CRT/DREs at the 3′-end of FLC, both in vitro and in vivo, and the CBFs levels increased gradually during vernalization. Additionally, vernalization-induced COOLAIR expression was highly suppressed in the cbfs mutant, in which all CBFs were knocked-out. Contrastingly, CBF-overexpressing plants showed COOLAIR upregulation, even at warm temperatures. We propose that COOLAIR is induced by CBFs in the early phase of vernalization but is downregulated as CBFs are evicted from closed FLC chromatin during the late vernalization phase. We also demonstrated that cbfs and COOLAIR mutants have a normal vernalization response, although they show defects in vernalization-induced COOLAIR activation, indicating that COOLAIR is not necessary for this process.

2021 ◽  
Vol 22 (23) ◽  
pp. 12678
Author(s):  
Eveline A. C. Goossens ◽  
Licheng Zhang ◽  
Margreet R. de Vries ◽  
J. Wouter Jukema ◽  
Paul H. A. Quax ◽  
...  

Inhibition of the 14q32 microRNAs, miR-329-3p and miR-495-3p, improves post-ischemic neovascularization. Cold-inducible RNA-binding protein (CIRBP) facilitates maturation of these microRNAs. We hypothesized that CIRBP deficiency improves post-ischemic angiogenesis via downregulation of 14q32 microRNA expression. We investigated these regulatory mechanisms both in vitro and in vivo. We induced hindlimb ischemia in Cirp−/− and C57Bl/6-J mice, monitored blood flow recovery with laser Doppler perfusion imaging, and assessed neovascularization via immunohistochemistry. Post-ischemic angiogenesis was enhanced in Cirp−/− mice by 34.3% with no effects on arteriogenesis. In vivo at day 7, miR-329-3p and miR-495-3p expression were downregulated in Cirp−/− mice by 40.6% and 36.2%. In HUVECs, CIRBP expression was upregulated under hypothermia, while miR-329-3p and miR-495-3p expression remained unaffected. siRNA-mediated CIRBP knockdown led to the downregulation of CIRBP-splice-variant-1 (CIRBP-SV1), CIRBP antisense long noncoding RNA (lncRNA-CIRBP-AS1), and miR-495-3p with no effects on the expression of CIRBP-SV2-4 or miR-329-3p. siRNA-mediated CIRBP knockdown improved HUVEC migration and tube formation. SiRNA-mediated lncRNA-CIRBP-AS1 knockdown had similar long-term effects. After short incubation times, however, only CIRBP knockdown affected angiogenesis, indicating that the effects of lncRNA-CIRBP-AS1 knockdown were secondary to CIRBP-SV1 downregulation. CIRBP is a negative regulator of angiogenesis in vitro and in vivo and acts, at least in part, through the regulation of miR-329-3p and miR-495-3p.


1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.


2018 ◽  
Vol 8 (3) ◽  
pp. 36-41
Author(s):  
Diep Do Thi Hong ◽  
Duong Le Phuoc ◽  
Hoai Nguyen Thi ◽  
Serra Pier Andrea ◽  
Rocchitta Gaia

Background: The first biosensor was constructed more than fifty years ago. It was composed of the biorecognition element and transducer. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples Glutamate is important biochemicals involved in energetic metabolism and neurotransmission. Therefore, biosensors requires the development a new approach exhibiting high sensibility, good reproducibility and longterm stability. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples. The aims of this work: To find out which concentration of polyethylenimine (PEI) exhibiting the most high sensibility, good reproducibility and long-term stability. Methods: We designed and developed glutamate biosensor using different concentration of PEI ranging from 0% to 5% at Day 1 and Day 8. Results: After Glutamate biosensors in-vitro characterization, several PEI concentrations, ranging from 0.5% to 1% seem to be the best in terms of VMAX, the KM; while PEI content ranging from 0.5% to 1% resulted stable, PEI 1% displayed an excellent stability. Conclusions: In the result, PEI 1% perfomed high sensibility, good stability and blocking interference. Furthermore, we expect to develop and characterize an implantable biosensor capable of detecting glutamate, glucose in vivo. Key words: Glutamate biosensors, PEi (Polyethylenimine) enhances glutamate oxidase, glutamate oxidase biosensors


Author(s):  
Fatima Aerts-Kaya

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marisa Nacke ◽  
Emma Sandilands ◽  
Konstantina Nikolatou ◽  
Álvaro Román-Fernández ◽  
Susan Mason ◽  
...  

AbstractThe signalling pathways underpinning cell growth and invasion use overlapping components, yet how mutually exclusive cellular responses occur is unclear. Here, we report development of 3-Dimensional culture analyses to separately quantify growth and invasion. We identify that alternate variants of IQSEC1, an ARF GTPase Exchange Factor, act as switches to promote invasion over growth by controlling phosphoinositide metabolism. All IQSEC1 variants activate ARF5- and ARF6-dependent PIP5-kinase to promote PI(3,4,5)P3-AKT signalling and growth. In contrast, select pro-invasive IQSEC1 variants promote PI(3,4,5)P3 production to form invasion-driving protrusions. Inhibition of IQSEC1 attenuates invasion in vitro and metastasis in vivo. Induction of pro-invasive IQSEC1 variants and elevated IQSEC1 expression occurs in a number of tumour types and is associated with higher-grade metastatic cancer, activation of PI(3,4,5)P3 signalling, and predicts long-term poor outcome across multiple cancers. IQSEC1-regulated phosphoinositide metabolism therefore is a switch to induce invasion over growth in response to the same external signal. Targeting IQSEC1 as the central regulator of this switch may represent a therapeutic vulnerability to stop metastasis.


Author(s):  
Zhibin Liao ◽  
Hongwei Zhang ◽  
Chen Su ◽  
Furong Liu ◽  
Yachong Liu ◽  
...  

Abstract Background Aberrant expressions of long noncoding RNAs (lncRNAs) have been demonstrated to be related to the progress of HCC. The mechanisms that SNHG14 has participated in the development of HCC are obscure. Methods Quantitative real-time PCR (qRT-PCR) was used to measure the lncRNA, microRNA and mRNA expression level. Cell migration, invasion and proliferation ability were evaluated by transwell and CCK8 assays. The ceRNA regulatory mechanism of SNHG14 was evaluated by RNA immunoprecipitation (RIP) and dual luciferase reporter assay. Tumorigenesis mouse model was used to explore the roles of miR-876-5p in vivo. The protein levels of SSR2 were measured by western blot assay. Results In this study, we demonstrated that SNHG14 was highly expressed in HCC tissues, meanwhile, the elevated expression of SNHG14 predicted poor prognosis in patients with HCC. SNHG14 promoted proliferation and metastasis of HCC cells. We further revealed that SNHG14 functioned as a competing endogenous RNA (ceRNA) for miR-876-5p and that SSR2 was a downstream target of miR-876-5p in HCC. Transwell, CCK8 and animal experiments exhibited miR-876-5p inhibited HCC progression in vitro and in vivo. By conducting rescue experiments, we found the overexpression of SSR2 or knocking down the level of miR-876-5p could reverse the suppressive roles of SNHG14 depletion in HCC. Conclusion SNHG14 promotes HCC progress by acting as a sponge of miR-876-5p to regulate the expression of SSR2 in HCC.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1210
Author(s):  
Xieguo Yan ◽  
Shiqiang Wang ◽  
Kaoxiang Sun

Schizophrenia, a psychiatric disorder, requires long-term treatment; however, large fluctuations in blood drug concentration increase the risk of adverse reactions. We prepared a long-term risperidone (RIS) implantation system that can stabilize RIS release and established in-vitro and in-vivo evaluation systems. Cumulative release, drug loading, and entrapment efficiency were used as evaluation indicators to evaluate the effects of different pore formers, polymer ratios, porogen concentrations, and oil–water ratios on a RIS implant (RIS-IM). We also built a mathematical model to identify the optimized formulation by stepwise regression. We also assessed the crystalline changes, residual solvents, solubility and stability after sterilization, in-vivo polymer degradation, pharmacokinetics, and tissue inflammation in the case of the optimized formulation. The surface of the optimized RIS microspheres was small and hollow with 134.4 ± 3.5 µm particle size, 1.60 SPAN, 46.7% ± 2.3% implant drug loading, and 93.4% entrapment efficiency. The in-vitro dissolution behavior of RIS-IM had zero-order kinetics and stable blood concentration; no lag time was released for over three months. Furthermore, the RIS-IM was not only non-irritating to tissues but also had good biocompatibility and product stability. Long-acting RIS-IMs with microspheres and film coatings can provide a new avenue for treating schizophrenia.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Jia ◽  
Junfeng Dao ◽  
Jiusong Han ◽  
Zhijie Huang ◽  
Xiang Sun ◽  
...  

Abstract Background Tongue squamous cell carcinoma (TSCC) is one of the most common oral tumors. Recently, long intergenic noncoding RNA 00958 (LINC00958) has been identified as an oncogene in human cancers. Nevertheless, the role of LINC00958 and its downstream mechanisms in TSCC is still unknown. Methods The effect of LINC00958 on TSCC cells proliferation and growth were assessed by CCK-8, colony formation, 5-Ethynyl-2′-deoxyuridline (EdU) assay and flow cytometry assays in vitro and tumor xenograft model in vivo. Bioinformatics analysis was used to predict the target of LINC00958 in TSCC, which was verified by RNA immunoprecipitation and luciferase reporter assays. Results LINC00958 was increased in TSCC tissues, and patients with high LINC00958 expression had a shorter overall survival. LINC00958 knockdown significantly decreased the growth rate of TSCC cells both in vitro and in vivo. In mechanism, LINC00958 acted as a ceRNA by competitively sponging miR-211-5p. In addition, we identified CENPK as a direct target gene of miR-211-5p, which was higher in TSCC tissues than that in adjacent normal tissues. Up-regulated miR-211-5p or down-regulated CENPK could abolish LINC00958-induced proliferation promotion in TSCC cells. Furthermore, The overexpression of CENPK promoted the expression of oncogenic cell cycle regulators and activated the JAK/STAT3 signaling. Conclusions Our findings suggested that LINC00958 is a potential prognostic biomarker in TSCC.


2021 ◽  
Vol 22 (13) ◽  
pp. 6663
Author(s):  
Maurycy Jankowski ◽  
Mariusz Kaczmarek ◽  
Grzegorz Wąsiatycz ◽  
Claudia Dompe ◽  
Paul Mozdziak ◽  
...  

Next-generation sequencing (RNAseq) analysis of gene expression changes during the long-term in vitro culture and osteogenic differentiation of ASCs remains to be important, as the analysis provides important clues toward employing stem cells as a therapeutic intervention. In this study, the cells were isolated from adipose tissue obtained during routine surgical procedures and subjected to 14-day in vitro culture and differentiation. The mRNA transcript levels were evaluated using the Illumina platform, resulting in the detection of 19,856 gene transcripts. The most differentially expressed genes (fold change >|2|, adjusted p value < 0.05), between day 1, day 14 and differentiated cell cultures were extracted and subjected to bioinformatical analysis based on the R programming language. The results of this study provide molecular insight into the processes that occur during long-term in vitro culture and osteogenic differentiation of ASCs, allowing the re-evaluation of the roles of some genes in MSC progression towards a range of lineages. The results improve the knowledge of the molecular mechanisms associated with long-term in vitro culture and differentiation of ASCs, as well as providing a point of reference for potential in vivo and clinical studies regarding these cells’ application in regenerative medicine.


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