scholarly journals TaWRKY13-A Serves as a Mediator of Jasmonic Acid-Related Leaf Senescence by Modulating Jasmonic Acid Biosynthesis

2021 ◽  
Vol 12 ◽  
Author(s):  
Hualiang Qiao ◽  
Yongwei Liu ◽  
Lingling Cheng ◽  
Xuelin Gu ◽  
Pengcheng Yin ◽  
...  
Keyword(s):  
Jasmonic Acid ◽  
Leaf Senescence ◽  
Brachypodium Distachyon ◽  
Wrky Transcription Factor ◽  
Luciferase Reporter ◽  
Virus Induced Gene Silencing ◽  
Reporter System ◽  
Mobility Shift ◽  
Yield And Quality ◽  
Mobility Shift Assay

Leaf senescence is crucial for crop yield and quality. Transcriptional regulation is a key step for integrating various senescence-related signals into the nucleus. However, few regulators of senescence implicating transcriptional events have been functionally characterized in wheat. Based on our RNA-seq data, we identified a WRKY transcription factor, TaWRKY13-A, that predominately expresses at senescent stages. By using the virus-induced gene silencing (VIGS) method, we manifested impaired transcription of TaWRKY13-A leading to a delayed leaf senescence phenotype in wheat. Moreover, the overexpression (OE) of TaWRKY13-A accelerated the onset of leaf senescence under both natural growth condition and darkness in Brachypodium distachyon and Arabidopsis thaliana. Furthermore, by physiological and molecular investigations, we verified that TaWRKY13-A participates in the regulation of leaf senescence via jasmonic acid (JA) pathway. The expression of JA biosynthetic genes, including AtLOX6, was altered in TaWRKY13-A-overexpressing Arabidopsis. We also demonstrated that TaWRKY13-A can interact with the promoter of AtLOX6 and TaLOX6 by using the electrophoretic mobility shift assay (EMSA) and luciferase reporter system. Consistently, we detected a higher JA level in TaWRKY13-A-overexpressing lines than that in Col-0. Moreover, our data suggested that TaWRKY13-A is partially functional conserved with AtWRKY53 in age-dependent leaf senescence. Collectively, this study manifests TaWRKY13-A as a positive regulator of JA-related leaf senescence, which could be a new clue for molecular breeding in wheat.

Abstract 1384: Osteogenic Transcription Factor Runx2 Regulates Expression of RANKL during VSMC Calcification

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Chang Hyun Byon ◽  
Jay McDonald ◽  
Yabing Chen
Keyword(s):  
Oxidative Stress ◽  
Transcription Factor ◽  
Molecular Mechanism ◽  
Luciferase Reporter ◽  
Rankl Expression ◽  
Reporter System ◽  
Mobility Shift ◽  
Atherosclerotic Lesions ◽  
Flanking Region

The expression of receptor activator of nuclear factor κ B (RANKL) is up-regulated in calcified atherosclerotic lesions, whereas it is frequently undetectable in normal vessels. The underlying molecular mechanism of increased expression of RANKL in calcified vessels is not known. We have previously demonstrated that oxidative stress induces calcification of vascular smooth muscle cells (VSMC) in vitro . Therefore, we determined whether oxidative stress regulates RANKL expression in VSMC and the underlying molecular mechanism. Consistent with previous observations in vivo , we found that the expression of RANKL in VSMC isolated from mouse. However, hydrogen peroxide (H 2 O 2 ), which induces VSMC calcification, induced a 33-fold increase in the transcripts of RANKL as determined by real-time PCR. Increased expression of RANKL protein was further confirmed by ELISA. Using flow cytometry, we demonstrated that membrane-bound RANKL was increased by oxidative stress. To characterize the molecular mechanism underlying H 2 O 2 -induced RANKL expression, we employed the luciferase reporter system with a series of deletion mutants of the RANKL 5′-flanking region. The H 2 O 2 responsive region is located between −200 to −400 in the 5′-flanking region of RANKL gene. Analyses of the sequence of this region identified multiple binding sites for the key osteogenic transcription factor, Runx2, which we previously reported to be an essential regulator of VSMC calcification. Electrophoretic mobility shift analyses demonstrated increased binding of Runx2 on the RANKL promoter sequence in nuclear extracts from VSMC exposed to H 2 O 2 . To further determine the role of Runx2 in regulating RANKL expression, we generated stable Runx2 knockdown VSMC with the use of lentivirus-carrying shRNA for Runx2 gene. H 2 O 2 -induced RANKL expression was abrogated in VSMC with Runx2 knockdown. In addition, adenovirus-mediated overexpression of Runx2 in VSMC induced the expression of RANKL. In summary, we have demonstrated that H 2 O 2 induces the expression of RANKL in VSMC, which is regulated by the osteogenic transcription factor Runx2. These observations provide novel molecular insights into the regulation of RANKL and its role on the pathogenesis of calcified atherosclerotic lesions.

Identification and characterization of the regulatory elements of the inducible acetamidase operon from Mycobacterium smegmatis

2007 ◽  
Vol 53 (5) ◽  
pp. 599-606 ◽  
Author(s):  
Selvakumar Subbian ◽  
Sujatha Narayanan
Keyword(s):  
Mycobacterium Smegmatis ◽  
Regulatory Elements ◽  
Growth Conditions ◽  
Open Reading Frames ◽  
Reporter System ◽  
Mobility Shift ◽  
Crude Cell Lysate ◽  
Multiple Promoters ◽  
Promoter Probe ◽  
Mobility Shift Assay

The highly inducible acetamidase promoter from Mycobacterium smegmatis has been used as a tool in the study of mycobacterial genetics. The 4.2 kb acetamidase operon contains four putative open reading frames (ORFs) (amiC, amiA, amiD, and amiS) upstream of the 1.2 kb acetamidase ORF (amiE). In this article, using electrophoretic mobility shift assay and promoter probe analyses with a lacZ reporter system, we show the position of three putative operators within the acetamidase operon in M. smegmatis. Results from these studies reinforce previous findings about the involvement of multiple promoters in the regulation of acetamidase gene expression. Each of the identified operators are positioned upstream of the respective promoter reported in previous studies. We also found that the crude cell lysate of M. smegmatis containing potential regulators, obtained from bacteria grown under inducing or noninducing conditions, binds to specific operators. The binding affinity of each operator with its cognate regulator is significantly different from the other. This supports not only the previous model of acetamidase gene regulation in M. smegmatis but also explains the role of these operators in controlling the expression of respective promoters under different growth conditions.

scholarly journals Downregulation of PU.1 Leads to Decreased Expression of Dectin-1 in Alveolar Macrophages during Pneumocystis Pneumonia

2010 ◽  
Vol 78 (3) ◽  
pp. 1058-1065 ◽  
Author(s):  
Chen Zhang ◽  
Shao-Hung Wang ◽  
Chung-Ping Liao ◽  
Shoujin Shao ◽  
Mark E. Lasbury ◽  
...  
Keyword(s):  
Alveolar Macrophages ◽  
Mrna Level ◽  
Gene Promoter ◽  
Pneumocystis Pneumonia ◽  
Luciferase Reporter ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Luciferase Reporter Gene ◽  
Mobility Shift ◽  
Mobility Shift Assay

ABSTRACT Dectin-1 is an important macrophage phagocytic receptor recognizing fungal β-glucans. In this study, the mRNA levels of the Dectin-1 gene were found to be decreased by 61% in alveolar macrophages (AMs) from Pneumocystis-infected mice. The expression of Dectin-1 protein on the surface of these cells was also significantly decreased. By fluorescence in situ hybridization, mRNA expression levels of the transcription factor PU.1 were also found to be significantly reduced in AMs from Pneumocystis-infected mice. Electrophoretic mobility shift assay showed that PU.1 protein bound Dectin-1 gene promoter. With a luciferase reporter gene driven by the Dectin-1 gene promoter, the expression of the PU.1 gene in NIH 3T3 cells was found to enhance the luciferase activity in a dose-dependent manner. PU.1 expression knockdown by small interfering RNA (siRNA) caused a 63% decrease in Dectin-1 mRNA level and 40% decrease in protein level in AMs. Results of this study indicate that downregulation of PU.1 during Pneumocystis pneumonia leads to decreased expression of Dectin-1 in AMs.

scholarly journals TLR4 promoter rs1927914 variant contributes to the susceptibility of esophageal squamous cell carcinoma in the Chinese population

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10754
Author(s):  
Jiaying Li ◽  
Hongjiao Wu ◽  
Hui Gao ◽  
Ruihuan Kou ◽  
Yuning Xie ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Statistical Significance ◽  
Nuclear Extract ◽  
Taqman Probe ◽  
Luciferase Reporter ◽  
Mobility Shift ◽  
Link Type ◽  
Pcr Rflp ◽  
Dna Protein Interaction ◽  
Mobility Shift Assay

Background Toll-like receptor 4 (TLR4), as a key regulator of both innate and acquired immunity, has been linked with the development of various cancers, including esophageal cancer. This study aims to analyze the association of potential functional genetic polymorphisms in TLR4 with the risk of esophageal cancer. Methods This case-control study involved in 480 ESCC patients and 480 health controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to genotype TLR4 rs1927914 polymorphism. Taqman probe method was used to determine the genotypes of TLR4 rs11536891 and rs7873784 variants. The relationship between TLR4 genetic variation and ESCC risk was analyzed by Logistic regression model by calculating the odds ratio (OR) and 95% confidence interval (95% CI). Results Compared with TLR4 rs1927914 AA genotype carriers, GG carriers had a lower ESCC risk (OR = 0.59, 95% CI [0.38–0.93], P = 0.023). Stratification analysis by age showed that TLR4 rs1927914 GG could affect the risk of ESCC in elderly people (OR = 0.59, 95% CI [0.36–0.97]). Smoking stratification analysis indicated that rs1927914 GG carriers were related to ESCC susceptibility among non-smokers (OR = 0.36, 95% CI [0.18–0.73]). Dual luciferase reporter assay suggested that rs1927914 G-containing TLR4 promoter displayed a 1.76-fold higher luciferase activity than rs1927914 A-containing counterpart in KYSE30 cells. Electrophoretic mobility shift assay (EMSA) showed the KYSE30 cell nuclear extract was able to bind the probe with rs1927914 G allele and this DNA-protein interaction could be eliminated by competition assays with unlabeled rs1927914 G probe, which indicating that the binding is sequence-specific. Our results also showed that TLR4 rs7873784 (G>C) and rs11536891 (T>C) conformed to complete genetic linkage. The genotype distributions of TLR4 rs11536891 variant among ESCC patients and normal controls have no statistical significance. Conclusion The TLR4 rs1927914 variant contributes to the ESCC risk by effecting the promoter activity.

scholarly journals Activation of the Transcription of BrGA20ox3 by a BrTCP21 Transcription Factor Is Associated with Gibberellin-Delayed Leaf Senescence in Chinese Flowering Cabbage during Storage

2019 ◽  
Vol 20 (16) ◽  
pp. 3860
Author(s):  
Xian-mei Xiao ◽  
Yan-mei Xu ◽  
Ze-xiang Zeng ◽  
Xiao-li Tan ◽  
Zong-li Liu ◽  
...  
Keyword(s):  
Transient Expression ◽  
Leaf Senescence ◽  
Biosynthetic Pathway ◽  
Transcript Level ◽  
Mobility Shift ◽  
Transient Expression Assay ◽  
Catabolic Genes ◽  
Mobility Shift Assay ◽  
Psii Quantum Yield ◽  
Senescence Associated Genes

Several lines of evidence have implicated the involvement of the phytohormone gibberellin (GA) in modulating leaf senescence in plants. However, upstream transcription factors (TFs) that regulate GA biosynthesis in association with GA-mediated leaf senescence remain elusive. In the current study, we report the possible involvement of a TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) TF BrTCP21 in GA-delayed leaf senescence in Chinese flowering cabbage. Exogenous GA3 treatment maintained a higher value of maximum PSII quantum yield (Fv/Fm) and total chlorophyll content, accompanied by the repression of the expression of senescence-associated genes and chlorophyll catabolic genes, which led to the delay of leaf senescence. A class I member of TCP TFs BrTCP21, was further isolated and characterized. The transcript level of BrTCP21 was low in senescing leaves, and decreased following leaf senescence, while GA3 could keep a higher expression level of BrTCP21. BrTCP21 was further found to be a nuclear protein and exhibit trans-activation ability through transient-expression analysis in tobacco leaves. Intriguingly, the electrophoretic mobility shift assay (EMSA) and transient expression assay illustrated that BrTCP21 bound to the promoter region of a GA biosynthetic gene BrGA20ox3, and activated its transcription. Collectively, these observations reveal that BrTCP21 is associated with GA-delayed leaf senescence, at least partly through the activation of the GA biosynthetic pathway. These findings expand our knowledge on the transcriptional mechanism of GA-mediated leaf senescence.

scholarly journals CCAAT Displacement Protein (CDP/cut) Recognizes a Silencer Element Within the Lactoferrin Gene Promoter

Blood ◽  
1997 ◽  
Vol 90 (7) ◽  
pp. 2784-2795 ◽  
Author(s):  
Arati Khanna-Gupta ◽  
Theresa Zibello ◽  
Sarah Kolla ◽  
Ellis J. Neufeld ◽  
Nancy Berliner
Keyword(s):  
Luciferase Activity ◽  
Gene Promoter ◽  
Luciferase Reporter ◽  
Transcriptional Level ◽  
Luciferase Reporter Gene ◽  
Mobility Shift ◽  
Ccaat Displacement Protein ◽  
Lactoferrin Gene ◽  
Mobility Shift Assay ◽  
Silencer Element

Abstract Expression of neutrophil secondary granule protein (SGP) genes is coordinately regulated at the transcriptional level, and is disrupted in specific granule deficiency and leukemia. We analyzed the regulation of SGP gene expression by luciferase reporter gene assays using the lactoferrin (LF) promoter. Reporter plasmids were transiently transfected into non–LF-expressing hematopoietic cell lines. Luciferase activity was detected from reporter plasmids containing basepair (bp) −387 to bp −726 of the LF promoter, but not in a −916-bp plasmid. Transfection of a −916-bp plasmid into a LF-expressing cell line resulted in abrogation of the silencing effect. Sequence analysis of this region revealed three eight-bp repetitive elements, the deletion of which restored wild-type levels of luciferase activity to the −916-bp reporter plasmid. Electrophoretic mobility shift assay and UV cross-linking analysis identified a protein of approximately 180 kD that binds to this region in non–LF-expressing cells but not in LF-expressing cells. This protein was identified to be the CCAAT displacement protein (CDP/cut). CDP/cut has been shown to downregulate expression of gp91-phox, a gene expressed relatively early in the myeloid lineage. Our observations suggest that the binding of CDP/cut to the LF silencer element serves to suppress basal promoter activity of the LF gene in non–LF-expressing cells. Furthermore, overexpression of CDP/cut in cultured myeloid stem cells blocks LF expression upon granulocyte colony-stimulating factor–induced neutrophil maturation without blocking phenotypic maturation. This block in LF expression may be due, in part, to the persistence of CDP/cut binding to the LF silencer element.

A WRKY transcription factor, TaWRKY40‐D, promotes leaf senescence associated with jasmonic acid and abscisic acid pathways in wheat

Plant Biology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 1072-1085
Author(s):  
L. Zhao ◽  
W. Zhang ◽  
Q. Song ◽  
Y. Xuan ◽  
K. Li ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Abscisic Acid ◽  
Jasmonic Acid ◽  
Leaf Senescence ◽  
Wrky Transcription Factor

scholarly journals A Cysteine-Rich Receptor-Like Protein Kinase CaCKR5 Contributes to Immune Defense Against Ralstonia Solanacearum in Pepper

2020 ◽  
Author(s):  
Shaoliang Mou ◽  
Feng Gao ◽  
Tingting Zhang ◽  
Weihong He ◽  
Qianqian Meng ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Green Fluorescence Protein ◽  
Immune Defense ◽  
Bimolecular Fluorescence Complementation ◽  
Pcr Analysis ◽  
Virus Induced Gene Silencing ◽  
Mobility Shift ◽  
Positive Role ◽  
Physiological Processes ◽  
Mobility Shift Assay

Abstract Background: Cysteine-rich receptor-like kinases (CRKs) represent a large subfamily of receptor-like kinases and have important roles in numerous different physiological processes in plants. Results: CaCRK5 transcripts were observed to accumulate after the inoculation of R. solanacearum and treatment with salicylic acid. The fusion between CaCRK5 and the green fluorescence protein was targeted to the plasma membrane. Suppression of CaCRK5 via virus-induced gene silencing made pepper plants significantly susceptible to R. solanacearum infection, which was accompanied by decreased expression of defense related genes CaPR1, CaSAR8.2, CaDEF1 and CaACO1. Overexpression of CaCRK5 in tobacco conferred increased resistance against R. solanacearum. Furthermore, electrophoretic mobility shift assay and chromatin immunoprecipitation with quantitative real-time PCR analysis verified that a homeodomain zipper I protein CaHDZ27 can bind to the CaCRK5 promoter, and directly active its expression. Yeast two-hybrid and bimolecular fluorescence complementation analyses suggested that CaCRK5 could heterodimerize with the homologous member CaCRK6 in the plasma membrane. Conclusions: Our data indicated that CaCRK5 played a positive role in pepper resistance against R. solanacearum infection.

scholarly journals A detailed and radioisotope-free protocol for electrophoretic mobility shift assay (EMSA)

2021 ◽  
Author(s):  
NGUYEN HOAI NGUYEN
Keyword(s):  
Transcription Factor ◽  
Electrophoretic Mobility Shift Assay ◽  
Electrophoretic Mobility ◽  
Chromatin Immunoprecipitation ◽  
Direct Interaction ◽  
Luciferase Reporter ◽  
Mobility Shift ◽  
Dna Fragment ◽  
Mobility Shift Assay

Abstract To comprehensively characterize the functions of a transcription factor (TF), it is required to analyze the interaction of this TF with its targeted loci. Several methods such as β-glucuronidase (GUS) or luciferase reporter, yeast one-hybrid (Y1H), chromatin-immunoprecipitation (ChIP), and electrophoretic mobility shift assay (EMSA) assays have been developed. Of these, EMSA is an in vitro method which can prove the direct interaction between TF and targeted DNA fragment. This protocol is to provide a detailed procedure for a safe EMSA assay (without using any radioisotope).

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