Expression of the CT Antigen, SPAN-Xb, Is Regulated through Promoter Methylation.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4285-4285
Author(s):  
Zhiqing Wang ◽  
Yana Zhang ◽  
Jian Zhang ◽  
Seah H. Lim

Abstract SPAN-Xb is a spermatid protein that we have recently identified as a novel Cancer-Testis (CT) antigen in hematologic malignancies. We have also shown that SPAN-Xb expression in tumor cell lines could be upregulated by 5-azacytidine, GM-CSF and IL-7. The ability of 5-azacytidine to increase SPAN-Xb expression suggests that SPAN-Xb gene expression, like the other CT antigens, may be regulated through promoter methylation. On the other hand, the ability of GM-CSF and IL-7 to increase SPAN-Xb expression remained to be determined. In this study, we set out to determine whether or not promoter methylation regulates SPAN-Xb gene expression and the effects of GM-CSF and IL-7 on SPAN-Xb expression is due to their action on the promoter activity. We first isolated and cloned the SPAN-Xb promoter gene into the CAT (chloramphenicol acetyl transferase) reporter system, pCAT*3-Enhancer vector. In vitro methylation was achieved using SssI methylase and the recombinant vectors were transfected into the myeloma cell line, RPMI 8226 cells. CAT activity was assayed in the lysate of the transfectants 48–72 hours after gene transfer. We observed that CAT activitiy in transfectants containining demethylated recombinant pCAT*3-SPAN-Xb promoter vector. In contrast, CAT activity was abrogated once the recombinant vector was methylated in vitro, supporting the role of DNA methylation in the regulation of SPAN-Xb gene expression. CAT activity in the transfectants containing the demethylated vector could be further increased by GM-CSF and IL-7, suggesting that the increase in SPAN-Xb expression we have observed in cells treated with GM-CSF and IL-7 may be the actions of these cytokines on the SPAN-Xb promoter. These cytokines alone, however, were unable to induce CAT activity since transfectants containing the methylated promoter sequence remained negative for the CAT activity even with the addition of GM-CSF or IL-7. To further evaluate the role of DNA methylation on the expression of SPAN-Xb, we carried out the bisulfite conversion assays using genomic DNA from tumor cell lines, normal testis, blood, kidney, pancreas and spleen. Following bisulfite conversion, the modified genomic DNA was subjected to PCR amplification, cloning and sequence analysis. Five clones from each tissues were randomly picked for sequence analysis. A total of 11 CpG islands were identified within the promoter sequence. They were put together into 7 groups according to their positions in the sequence: Group I: −502; Group II: −474; Group III: −450; Group IV: −341; Group V: −311 to −300; Group VI: −226 to −222; Group VII: −184 to −181. Following sequence analysis, we observed that SPAN-Xb expressor (normal testis) was consistently demethylated within Groups V and VI CpG islands. In contrast, SPAN-Xb-negative tissues were consistently methylated at these two CpG islands, localizing the promoter activity of the sequence to these two areas of the promoter. The methylation status at the other CpG island did not predict SPAN-Xb expression. We therefore conclude that: 1. SPAN-Xb expression is regulated by promoter methylation; 2. GM-CSF and IL-7 increase SPAN-Xb expression through their action on the SPAN-Xb promoter, and; 3. The CpG islands between −311 and −300 and −226 and −222 are the regions within the SPAN-Xb promoter sequence that control gene expression.

2012 ◽  
Vol 302 (5) ◽  
pp. L447-L454 ◽  
Author(s):  
Louis R. Standiford ◽  
Theodore J. Standiford ◽  
Michael J. Newstead ◽  
Xianying Zeng ◽  
Megan N. Ballinger ◽  
...  

Toll-like receptors (TLRs) are required for protective host defense against bacterial pathogens. However, the role of TLRs in regulating lung injury during Gram-negative bacterial pneumonia has not been thoroughly investigated. In this study, experiments were performed to evaluate the role of TLR4 in pulmonary responses against Klebsiella pneumoniae (Kp). Compared with wild-type (WT) (Balb/c) mice, mice with defective TLR4 signaling (TLR4lps-d mice) had substantially higher lung bacterial colony-forming units after intratracheal challenge with Kp, which was associated with considerably greater lung permeability and lung cell death. Reduced expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA and protein was noted in lungs and bronchoalveolar lavage fluid of TLR4 mutant mice postintratracheal Kp compared with WT mice, and primary alveolar epithelial cells (AEC) harvested from TLR4lps-d mice produced significantly less GM-CSF in vitro in response to heat-killed Kp compared with WT AEC. TLR4lps-d AEC underwent significantly more apoptosis in response to heat-killed Kp in vitro, and treatment with GM-CSF protected these cells from apoptosis in response to Kp. Finally, intratracheal administration of GM-CSF in TLR4lps-d mice significantly decreased albumin leak, lung cell apoptosis, and bacteremia in Kp-infected mice. Based on these observations, we conclude that TLR4 plays a protective role on lung epithelium during Gram-negative bacterial pneumonia, an effect that is partially mediated by GM-CSF.


Development ◽  
1997 ◽  
Vol 124 (21) ◽  
pp. 4243-4252 ◽  
Author(s):  
S.K. Kim ◽  
M. Hebrok ◽  
D.A. Melton

The role of the notochord in inducing and patterning adjacent neural and mesodermal tissues is well established. We provide evidence that the notochord is also required for one of the earliest known steps in the development of the pancreas, an endodermally derived organ. At a developmental stage in chick embryos when the notochord touches the endoderm, removal of notochord eliminates subsequent expression of several markers of dorsal pancreas bud development, including insulin, glucagon and carboxypeptidase A. Pancreatic gene expression can be initiated and maintained in prepancreatic chick endoderm grown in vitro with notochord. Non-pancreatic endoderm, however, does not express pancreatic genes when recombined with the same notochord. The results suggest that the notochord provides a permissive signal to endoderm to specify pancreatic fate in a stepwise manner.


2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Gwang Sik Kim ◽  
Young Chul Lee

Med6 protein (Med6p) is a hallmark component of evolutionarily conserved Mediator complexes, and the genuine role of Med6p in Mediator functions remains elusive. For the functional analysis ofSaccharomyces cerevisiaeMed6p (scMed6p), we generated a series of scMed6p mutants harboring a small internal deletion. Genetic analysis of these mutants revealed that three regions (amino acids 33–42 (Δ2), 125–134 (Δ5), and 157–166 (Δ6)) of scMed6p are required for cell viability and are located at highly conserved regions of Med6 homologs. Notably, the Med6p-Δ2 mutant was barely detectable in whole-cell extracts and purified Mediator, suggesting a loss of Mediator association and concurrent rapid degradation. Consistent with this, the recombinant forms of Med6p having these mutations partially (Δ2) restore or fail (Δ5 and Δ6) to restore in vitro transcriptional defects caused by temperature-sensitivemed6mutation. In an artificial recruitment assay, Mediator containing a LexA-fused wild-type Med6p or Med6p-Δ5 was recruited to thelexAoperator region with TBP and activated reporter gene expression. However, the recruitment of Mediator containing LexA-Med6p-Δ6 tolexAoperator region resulted in neither TBP recruitment nor reporter gene expression. This result demonstrates a pivotal role of Med6p in the postrecruitment function of Mediator, which is essential for transcriptional activation by Mediator.


2021 ◽  
Author(s):  
Hijam Nonibala ◽  
Braj Bansh Prasad Gupta

Abstract Transcription of arylalkylamine N-acetyltransferase 2 (aanat2) gene leads to formation of AANAT2 - the rate-limiting enzyme in melatonin synthesis pathway in photosensitive fish pineal organ. However, unlike in avian and mammalian pineal gland, there is practically no information on signal transduction pathway(s) involved in regulation of aanat2 gene transcription in the fish pineal organ. Therefore, we investigated the role of important molecular components of signalling via cAMP, cGMP, Ca2+ involving PKA, PKG, PKC, MeK and p38 MAP kinase as well as possible role of serine/threonine phosphatases, CREB and CBP using their specific inhibitors and/or activators in aanat2 gene transcription in the fish pineal organ maintained under in vitro culture-conditions. db-cAMP and db-cGMP stimulated the expression of aanat2 gene. db-cAMP- and cGMP-induced aanat2 gene expression was significantly reduced in the presence of H-89 (specific inhibitor of PKA), KT5823 (specific inhibitor of PKG), chelerythrine chloride (specific inhibitor of PKC), U0126 ethanolate (specific inhibitor of MeK) and SB 202190 monohydrochloride hydrate (specific inhibitor of p38 MAP kinase). Inhibitors of PP1 and PP2A significantly increased aanat2 gene expression as well as significantly reduced cAMP- and cGMP-induced gene transcription, while inhibitor of PP2B had no effect on aanat2 gene expression. Inhibitors of both CREB and CBP-CREB interaction completely blocked cAMP-induced aanat2 gene transcription. Based on these findings, we suggest that cAMP, cGMP and Ca2+ stimulate aanat2 gene transcription via PKA, PKG and PKC, respectively. Further, protein phosphatases and CBP-CREB-CRE pathway are actively involved in regulation of on aanat2 gene expression in the fish pineal organ.


2020 ◽  
Author(s):  
Joanna Houghton ◽  
Angela Rodgers ◽  
Graham Rose ◽  
Kristine B. Arnvig

ABSTRACTAlmost 140 years after the identification of Mycobacterium tuberculosis as the etiological agent of tuberculosis, important aspects of its biology remain poorly described. Little is known about the role of post-transcriptional control of gene expression and RNA biology, including the role of most of the small RNAs (sRNAs) identified to date. We have carried out a detailed investigation of the M. tuberculosis sRNA, F6, and show it to be dependent on SigF for expression and significantly induced during in vitro starvation and in a mouse model of infection. However, we found no evidence of attenuation of a ΔF6 strain within the first 20 weeks of infection. A further exploration of F6 using in vitro models of infection suggests a role for F6 as a highly specific regulator of the heat shock repressor, HrcA. Our results point towards a role for F6 during periods of low metabolic activity similar to cold shock and associated with nutrient starvation such as that found in human granulomas in later stages of infection.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
I Muñoa ◽  
M Araolaza-Lasa ◽  
I Urizar-Arenaza ◽  
M Gianzo Citores ◽  
N Subiran Ciudad

Abstract Study question To elucidate if morphine can alter embryo development. Summary answer Chronic morphine treatment regulates BMP4 growth factor, in terms of gene expression and H3K27me3 enrichment and promotes in-vitro blastocysts development and PGC formation. What is known already BMP4 is a member of the bone morphogenetic protein family, which acts mainly through SMAD dependent pathway, to play an important role in early embryo development. Indeed, BMP4 enhances pluripotency in mouse embryonic stem cells (mESCs) and, specifically, is involved in blastocysts formation and primordial germ cells (PGCs) generation. Although, external morphine influence has been previously reported on the early embryo development, focus on implantation and uterus function, there is a big concern in understanding how environmental factors can cause stable epigenetic changes, which could be maintained during development and lead to health problems. Study design, size, duration First, OCT4-reported mESCs were chronically treated with morphine during 24h, 10–5mM. After morphine removal, mESCs were collected for RNA-seq and H3K27me3 ChIP-seq study. To elucidate the role of morphine in early embryo development, two cell- embryos stage were chronically treated with morphine for 24h and in-vitro cultured up to the blastocyst stage in the absence of morphine. Furthermore, after morphine treatment mESCs were differentiated to PGCs, to elucidate the role of morphine in PGC differentiation. Participants/materials, setting, methods Transcriptomic analyses and H3K27me3 genome wide distribution were carried out by RNA-Sequencing and Chip-Sequencing respectively. Validations were performed by RNA-RT-qPCR and Chip-RT-qPCR. Main results and the role of chance Dynamic transcriptional analyses identified a total of 932 differentially expressed genes (DEGs) after morphine treatment on mESCs, providing strong evidence of a transcriptional epigenetic effect induced by morphine. High-throughput screening approaches showed up Bmp4 as one of the main morphine targets on mESCs. Morphine caused an up-regulation of Bmp4 gene expression together with a decrease of H3K27me3 enrichment at promoter level. However, no significant differences were observed on gene expression and H3K27me3 enrichment on BMP4 signaling pathway components (such as Smad1, Smad4, Smad5, Smad7, Prdm1 and Prmd14) after morphine treatment. On the other hand, the Bmp4 gene expression was also up-regulated in in-vitro morphine treated blastocyst and in-vitro morphine treated PGCs. These results were consistent with the increase in blastocyst rate and PGC transformation rate observed after morphine chronic treatment. Limitations, reasons for caution To perform the in-vitro analysis. Further studies are needed to describe the whole signaling pathways underlying BMP4 epigenetic regulation after morphine treatment. Wider implications of the findings: Our findings confirmed that mESCs and two-cell embryos are able to memorize morphine exposure and promote both blastocyst development and PGCs formation through potentially BMP4 epigenetic regulation. These results provide insights understanding how environmental factors can cause epigenetic changes during the embryo development, leading to alterations and producing health problems/diseases Trial registration number Not applicable


2021 ◽  
Vol 21 ◽  
Author(s):  
Xinwei Huang ◽  
Xiuqing Li ◽  
Lijuan Yang ◽  
Pengfei Wang ◽  
Jingyuan Yan ◽  
...  

Aims: We aim to define parameters affecting the safety and long-term transgene expression of attenuated HSV-1 vectors and optimize the expression cassettes to achieve robust and sustained expression in CNS. Background: Engineered, attenuated Herpes simplex virus (HSV) vectors are promising vehicles for gene delivery to the peripheral and central nervous systems. The virus latent promoter (LAP) is commonly used to drive exogenous gene expression; however, parameters affecting the safety and long-term transgene expression of attenuated HSV-1 vectors have not been fully understood. Objective: This study aimed to construct attenuated HSV-1 vectors using the CRISPR-Cas9 system and examine the influence of transgene cassette construction and insertion site on transgene expression and vector safety. Method: In this study, we used a CRISPR-Cas9 system to accurately and efficiently edit attenuated HSV-1 strain 1716, and constructed two series of recombinant virus LMR and LMRx with different sets of gene cassettes insertion in Exon1(LAP2) and 2.0 kb intron downstream of LAP, respectively. The transgene expression and viral gene transcriptional kinetics were compared in in-vitro cell lines. The reporter gene expression and safety profiles of each vector were further evaluated in the mouse hippocampus gene transduction model. Result: The in-vitro cell line analysis indicated that the insertion of a gene expression cassette would disrupt virus gene transcription. Mouse hippocampus transducing analysis suggested that complete expression cassette insertion at 2.0 kb intron could achieve robust and longtime gene expression than the other constructs. Recombinants with gene expression cassettes lacked Poly (A), which induced significant neuronal inflammation due to persistent viral antigen expression and microglia activation. Conclusion: Our results indicated that the integrity of LAT transcripts was not necessary for the establishment of long-term latent expression. Exogenous strong promoters (like cBh promoter) could remain active during latency when placed in Exon1 or 2.0 Kb Intron of LAT locus, although their transcriptional activity declined with time. Consistent with previous research, the foreign gene expression would last much longer when the gene cassette was located downstream of Exon1, which suggested a role of LAP2 in maintaining promoter activity during latency. Besides, over-transcription of the downstream part of LAT may induce continuous activation of the attenuated vectors, suggesting an important role of LAT in maintaining viral reactivation potential.


2018 ◽  
pp. 1-6
Author(s):  
Neemat M. Kassem ◽  
Alya M. Ayad ◽  
Noha M. El Husseiny ◽  
Doaa M. El-Demerdash ◽  
Hebatallah A. Kassem ◽  
...  

Purpose Granulocyte-macrophage colony-stimulating factor (GM-CSF) cytokine stimulates growth, differentiation, and function of myeloid progenitors. We aimed to study the role of GM-CSF gene expression, its protein, and antibodies in patients with acute myeloid leukemia/myelodysplastic syndromes (AML/MDS) and their correlation to disease behavior and treatment outcome. The study included 50 Egyptian patients with AML/MDS in addition to 20 healthy volunteers as control subjects. Patients and Methods Assessment of GM-CSF gene expression was performed by quantitative real-time polymerase chain reaction. GM-CSF proteins and antibodies were assessed by enzyme-linked immunosorbent assay. Results There was significant decrease in GM-CSF gene expression ( P = .008), increase in serum level of GM-CSF protein ( P = .0001), and increase in anti–GM-CSF antibodies ( P = .001) in patients with AML/MDS compared with healthy control subjects. In addition, there was a significant negative correlation between serum levels of GM-CSF protein and initial peripheral blood blasts, percentage as well as response to therapy. Conclusion Any alteration in GM-CSF gene expression could have implications in leukemogenesis. In addition, GM-CSF protein serum levels could be used to predict outcome of therapy. GM-CSF antibodies may also play a role in the pathogenesis of AML/MDS. The use of these GM-CSF parameters for disease monitoring and as markers of disease activity needs further research.


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