scholarly journals Different Patterns of Regulation for the Copper and Cadmium Metallothioneins of the Ectomycorrhizal Fungus Hebeloma cylindrosporum

2009 ◽  
Vol 75 (8) ◽  
pp. 2266-2274 ◽  
Author(s):  
G. Ramesh ◽  
G. K. Podila ◽  
G. Gay ◽  
R. Marmeisse ◽  
M. S. Reddy

ABSTRACT Metallothioneins (MTs) are small cysteine-rich peptides involved in metal homeostasis and detoxification. We have characterized two MT genes, HcMT1 and HcMT2, from the ectomycorrhizal fungus Hebeloma cylindrosporum in this study. Expression of HcMT1 and HcMT2 in H. cylindrosporum under metal stress conditions was studied by competitive reverse transcription-PCR analysis. The full-length cDNAs were used to perform functional complementation in mutant strains of Saccharomyces cerevisiae. As revealed by heterologous complementation assays in yeast, HcMT1 and HcMT2 each encode a functional polypeptide capable of conferring increased tolerance against Cd and Cu, respectively. The expression levels of HcMT1 were observed to be at their maximum at 24 h, and they increased as a function of Cu concentration. HcMT2 was also induced by Cu, but the expression levels were lower than those for HcMT1. The mRNA accumulation of HcMT1 was not influenced by Cd, whereas Cd induced the transcription of HcMT2. Zn, Pb, and Ni did not affect the transcription of HcMT1 or of HcMT2. Southern blot analysis revealed that both of these genes are present as a single copy in H. cylindrosporum. While the promoters of both HcMT1 and HcMT2 contained the standard stress response elements implicated in the metal response, the numbers and varieties of potential regulatory elements were different in these promoters. These results show that ectomycorrhizal fungi encode different MTs and that each of them has a particular pattern of expression, suggesting that they play critical specific roles in improving the survival and growth of ectomycorrhizal trees in ecosystems contaminated by heavy metals.

2008 ◽  
Vol 191 (3) ◽  
pp. 1056-1065 ◽  
Author(s):  
Jiaqin Zhang ◽  
Anirban Banerjee ◽  
Indranil Biswas

ABSTRACT Streptococcus mutans, the primary causative agent of human dental caries, contains a single copy of the gene encoding ClpP, the chief intracellular protease responsible for tolerance to various environmental stresses. To better understand the role of ClpP in stress response, we investigated the regulation of clpP expression in S. mutans. Using semiquantitative reverse transcription-PCR analysis, we observed that, under nonstressed conditions, clpP expression is somewhat constant throughout the growth phases, although it gradually decreases as cells enter the late stationary phase. The half-life of the clpP transcript was found to be less than 1 minute. Sequence analysis of the clpP locus reveals the presence of a 50-bp tandem repeat sequence located immediately upstream of the clpP promoter (PclpP). PCR and DNA sequence analyses suggest that the number of tandem repeat units can vary from as few as two to as many as nine, depending on the particular S. mutans isolate. Further analysis, using a transcriptional reporter fusion consisting of PclpP fused to a promoterless gusA gene, indicates that the presence of the repeat sequence region within PclpP results in an approximately fivefold increase in expression from PclpP compared to the repeat-free transcriptional reporter fusion. CtsR, a transcriptional repressor that negatively regulates clpP expression, has no effect on this repeat-mediated induction of clpP transcription. Furthermore, the repeat sequence is not necessary for the induction of clpP under stress conditions. Database searches indicate that the region containing the tandem repeats is absent in the clpP loci in other bacteria, including other closely related Streptococcus spp., suggesting that the repeat sequences are specific for the induction of clpP expression in S. mutans. We speculate that a host-specific transcriptional activator might be involved in the upregulation of clpP expression in S. mutans.


2005 ◽  
Vol 187 (5) ◽  
pp. 1763-1772 ◽  
Author(s):  
Kunihiko Nishino ◽  
Takeshi Honda ◽  
Akihito Yamaguchi

ABSTRACT The BaeSR two-component regulatory system controls expression of exporter genes conferring drug resistance in Escherichia coli (S. Nagakubo, K. Nishino, T. Hirata, and A. Yamaguchi, J. Bacteriol. 184:4161-4167, 2002; N. Baranova and H. Nikaido, J. Bacteriol. 184:4168-4176, 2002). To understand the whole picture of BaeSR regulation, a DNA microarray analysis of the effect of BaeR overproduction was performed. BaeR overproduction activated 59 genes related to two-component signal transduction, chemotactic responses, flagellar biosynthesis, maltose transport, and multidrug transport, and BaeR overproduction also repressed the expression of the ibpA and ibpB genes. All of the changes in the expression levels were also observed by quantitative real-time reverse transcription-PCR analysis. The expression levels of 15 of the 59 BaeR-activated genes were decreased by deletion of baeSR. Of 11 genes induced by indole (a putative inducer of the BaeSR system), 10 required the BaeSR system for induction. Combination of the expression data sets revealed a BaeR-binding site sequence motif, 5′-TTTTTCTCCATDATTGGC-3′ (where D is G, A, or T). Several genes up-regulated by BaeR overproduction, including genes for maltose transport, chemotactic responses, and flagellar biosynthesis, required an intact PhoBR or CreBC two-component regulatory system for up-regulation. These data indicate that there is cross-regulation among the BaeSR, PhoBR, and CreBC two-component regulatory systems. Such a global analysis should reveal the regulatory network of the BaeSR system.


2006 ◽  
Vol 291 (5) ◽  
pp. E1092-E1099 ◽  
Author(s):  
Hidehiko Kondo ◽  
Yoshihiko Minegishi ◽  
Yumiko Komine ◽  
Takuya Mori ◽  
Ichiro Matsumoto ◽  
...  

The effects of high-fat (HF) feeding on gene expression in the small intestine were examined using obesity-resistant A/J mice and obesity-prone C57BL/6J (B6) mice. Both strains of mice were maintained on low-fat (LF; 5% fat) or HF (30% fat) diets for 2 wk. Quantitative reverse transcription-PCR analysis revealed that lipid metabolism-related genes, including carnitine palmitoyltransferase (CPT) I, liver fatty acid binding protein, pyruvate dehydrogenase kinase-4, and NADP+-dependent cytosolic malic enzyme, were upregulated by HF feeding in both strains of mice. The upregulated gene expression levels were higher in A/J mice than in B6 mice, suggesting more active lipid metabolism in the small intestine of A/J mice. The prominent upregulation of the lipid metabolism-related genes were specific to the small intestine; the expression levels were little or unchanged in the liver, muscle, and white adipose tissue. The increase by HF feeding and predominant expression of the intestinal lipid metabolism-related genes in A/J mice were reflected in the enzyme activities; malic enzyme, CPT, and β-oxidation activities were increased by HF feeding, and the upregulated malic enzyme and CPT activities were significantly higher in obesity-resistant A/J mice compared with those in obesity-prone B6 mice. These findings suggest that intestinal lipid metabolism is associated with susceptibility to obesity.


2003 ◽  
Vol 69 (4) ◽  
pp. 2269-2275 ◽  
Author(s):  
M. E. Corbella ◽  
A. Puyet

ABSTRACT Pseudomonas aeruginosa JB2 can use 2-chlorobenzoate (2-CBa), 3-CBa, 2,3-dichlorobenzoate (2,3-DCBa), and 2,5-DCBa as sole carbon and energy sources, whereas strain 142 can only grow on 2-CBa and 2,4-DCBa. Both strains, however, harbor the same halobenzoate 1,2-dioxygenase (ohbAB) and chlorocatechol (clcABD) degradation genes necessary for the metabolism of ortho-CBas. In addition, the hybABCD operon, encoding a salicylate 5-hydroxylase, is also found in both strains. The expression of ohbAB, hybABCD, and clcABD operons was measured in cultures grown on different CBas as the sole carbon source and also in glucose-grown cells supplemented with CBas as inducers. A method to standardize real-time reverse transcription-PCR experimental data was used that allows the comparison of semiquantitative mRNA accumulation in different strains and culture conditions. In both strains, the ohb and hyb systems were induced in cells grown on 2-CBa or DCBas, whereas clc was induced only by DCBas. Repression by catabolite was observed both on ohb and clc systems in glucose-grown cells. Chlorocatechol 1,2-dioxygenase activity in JB2 was detected even in clc-repressed conditions, confirming the presence of additional isofunctional genes previously detected in P. aeruginosa 142. Although similar levels of induction of ohbAB were observed in strain JB2 grown on either benzoate, monochlorobenzoates, or DCBas, the ohbAB operon of strain 142 was only strongly induced by growth on 2-CBa and, to a lesser extent, on 2,4-DCBa. This observation suggests that regulation of the ohbAB operon may be different in both strains. The concomitant induction of ohb and hyb by CBas may allow the formation of hybrid halobenzoate dioxygenase(s) composed of Ohb/Hyb dioxygenase subunits and Hyb ferredoxin/ferredoxin reductase components.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fan Liu ◽  
Hua Li ◽  
Junwei Wu ◽  
Bin Wang ◽  
Na Tian ◽  
...  

AbstractThe LOX genes have been identified and characterized in many plant species, but studies on the banana LOX genes are very limited. In this study, we respectively identified 18 MaLOX, 11 MbLOX, and 12 MiLOX genes from the Musa acuminata, M. balbisiana and M. itinerans genome data, investigated their gene structures and characterized the physicochemical properties of their encoded proteins. Banana LOXs showed a preference for using and ending with G/C and their encoded proteins can be classified into 9-LOX, Type I 13-LOX and Type II 13-LOX subfamilies. The expansion of the MaLOXs might result from the combined actions of genome-wide, tandem, and segmental duplications. However, tandem and segmental duplications contribute to the expansion of MbLOXs. Transcriptome data based gene expression analysis showed that MaLOX1, 4, and 7 were highly expressed in fruit and their expression levels were significantly regulated by ethylene. And 11, 12 and 7 MaLOXs were found to be low temperature-, high temperature-, and Fusarium oxysporum f. sp. Cubense tropical race 4 (FocTR4)-responsive, respectively. MaLOX8, 9 and 13 are responsive to all the three stresses, MaLOX4 and MaLOX12 are high temperature- and FocTR4-responsive; MaLOX6 and MaLOX17 are significantly induced by low temperature and FocTR4; and the expression of MaLOX7 and MaLOX16 are only affected by high temperature. Quantitative real-time PCR (qRT-PCR) analysis revealed that the expression levels of several MaLOXs are regulated by MeJA and FocTR4, indicating that they can increase the resistance of banana by regulating the JA pathway. Additionally, the weighted gene co-expression network analysis (WGCNA) of MaLOXs revealed 3 models respectively for 5 (MaLOX7-11), 3 (MaLOX6, 13, and 17), and 1 (MaLOX12) MaLOX genes. Our findings can provide valuable information for the characterization, evolution, diversity and functionality of MaLOX, MbLOX and MiLOX genes and are helpful for understanding the roles of LOXs in banana growth and development and adaptations to different stresses.


Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 1202-1212
Author(s):  
Aichun Zhang ◽  
Yangzi Jin

AbstractAllergic rhinitis (AR) is one of the most common chronic diseases. This study examined whether microRNA (miR)-182-5p plays a role in AR by regulating toll-like receptor 4 (TLR4). First, data demonstrated that TLR4 was a target of miR-182-5p. Subsequently, AR mouse model was established to explore the role of miR-182-5p and TLR4 in AR in vivo. Initially, quantitative reverse transcription-PCR (qRT-PCR) analysis indicated that miR-182-5p was downregulated, while TLR4 expression was upregulated in AR mice. Then we found that miR-182-5p mimic reduced the frequency of sneezing and nose rubbing of the AR mice. In addition, miR-182-5p mimic significantly increased ovalbumin (OVA)-specific IgE and leukotriene C4 expression levels in nasal lavage fluid (NLF) and serum of AR mice. miR-182-5p mimic decreased the number of inflammatory cells in NLF of AR mice. It also reduced the levels of inflammatory factors in the serum of AR mice, such as interleukin (IL)-4, IL-5, IL-13, IL-17 and tumor necrosis factor (TNF)-α, while increasing the release of IFN-γ and IL-2. Finally, miR-182-5p mimic inhibited NF-κB signaling pathway activation in AR mice. However, all effects of miR-182-5p mimic on AR mice were reversed by TLR4-plasmid. In conclusion, miR-182-5p/TLR4 axis may represent a novel therapeutic target for AR.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ruifeng Cui ◽  
Xiaoge Wang ◽  
Waqar Afzal Malik ◽  
Xuke Lu ◽  
Xiugui Chen ◽  
...  

Abstract Background The Raffinose synthetase (RAFS) genes superfamily is critical for the synthesis of raffinose, which accumulates in plant leaves under abiotic stress. However, it remains unclear whether RAFS contributes to resistance to abiotic stress in plants, specifically in the Gossypium species. Results In this study, we identified 74 RAFS genes from G. hirsutum, G. barbadense, G. arboreum and G. raimondii by using a series of bioinformatic methods. Phylogenetic analysis showed that the RAFS gene family in the four Gossypium species could be divided into four major clades; the relatively uniform distribution of the gene number in each species ranged from 12 to 25 based on species ploidy, most likely resulting from an ancient whole-genome polyploidization. Gene motif analysis showed that the RAFS gene structure was relatively conservative. Promoter analysis for cis-regulatory elements showed that some RAFS genes might be regulated by gibberellins and abscisic acid, which might influence their expression levels. Moreover, we further examined the functions of RAFS under cold, heat, salt and drought stress conditions, based on the expression profile and co-expression network of RAFS genes in Gossypium species. Transcriptome analysis suggested that RAFS genes in clade III are highly expressed in organs such as seed, root, cotyledon, ovule and fiber, and under abiotic stress in particular, indicating the involvement of genes belonging to clade III in resistance to abiotic stress. Gene co-expressed network analysis showed that GhRFS2A-GhRFS6A, GhRFS6D, GhRFS7D and GhRFS8A-GhRFS11A were key genes, with high expression levels under salt, drought, cold and heat stress. Conclusion The findings may provide insights into the evolutionary relationships and expression patterns of RAFS genes in Gossypium species and a theoretical basis for the identification of stress resistance materials in cotton.


2021 ◽  
Vol 22 (10) ◽  
pp. 5221
Author(s):  
Danqi Zeng ◽  
Jaime A. Teixeira da Silva ◽  
Mingze Zhang ◽  
Zhenming Yu ◽  
Can Si ◽  
...  

The APETALA2 (AP2) transcription factors (TFs) play crucial roles in regulating development in plants. However, a comprehensive analysis of the AP2 family members in a valuable Chinese herbal orchid, Dendrobium officinale, or in other orchids, is limited. In this study, the 14 DoAP2 TFs that were identified from the D. officinale genome and named DoAP2-1 to DoAP2-14 were divided into three clades: euAP2, euANT, and basalANT. The promoters of all DoAP2 genes contained cis-regulatory elements related to plant development and also responsive to plant hormones and stress. qRT-PCR analysis showed the abundant expression of DoAP2-2, DoAP2-5, DoAP2-7, DoAP2-8 and DoAP2-12 genes in protocorm-like bodies (PLBs), while DoAP2-3, DoAP2-4, DoAP2-6, DoAP2-9, DoAP2-10 and DoAP2-11 expression was strong in plantlets. In addition, the expression of some DoAP2 genes was down-regulated during flower development. These results suggest that DoAP2 genes may play roles in plant regeneration and flower development in D. officinale. Four DoAP2 genes (DoAP2-1 from euAP2, DoAP2-2 from euANT, and DoAP2-6 and DoAP2-11 from basal ANT) were selected for further analyses. The transcriptional activation of DoAP2-1, DoAP2-2, DoAP2-6 and DoAP2-11 proteins, which were localized in the nucleus of Arabidopsis thaliana mesophyll protoplasts, was further analyzed by a dual-luciferase reporter gene system in Nicotiana benthamiana leaves. Our data showed that pBD-DoAP2-1, pBD-DoAP2-2, pBD-DoAP2-6 and pBD-DoAP2-11 significantly repressed the expression of the LUC reporter compared with the negative control (pBD), suggesting that these DoAP2 proteins may act as transcriptional repressors in the nucleus of plant cells. Our findings on AP2 genes in D. officinale shed light on the function of AP2 genes in this orchid and other plant species.


2003 ◽  
Vol 69 (11) ◽  
pp. 6541-6549 ◽  
Author(s):  
Gilbert Thierry Lamothe ◽  
Thierry Putallaz ◽  
Han Joosten ◽  
Joey D. Marugg

ABSTRACT A seminested reverse transcription-PCR method coupled to membrane filtration was optimized to investigate the presence of norovirus (NV) RNA sequences in bottled and natural mineral waters. The recovery of viral particles by filtration varied between 28 and 45%, while the limit of detection of the overall method ranged from 6 to 95 viral particles. The assay was broadly reactive, as shown by the successful detection of 27 different viral strains representing 12 common genotypes of NVs. A total of 718 bottled and natural mineral water samples were investigated, including 640 samples of finished, spring, and line products (mostly 1 to 1.5 liters), collected from 36 different water brands of various types and from diverse geographic origins over a 2-year period. In addition, 78 samples of larger volume (10 and 400 to 500 liters) and environmental swabs were investigated. From the 1,436 analyses that were performed for the detection of NVs belonging to genogroups I and II, 34 samples (2.44%) were presumptively positive by seminested RT-PCR. However, confirmation by DNA sequence analysis revealed that all presumptive positive results were either due to nonspecific amplification or to cross-contamination. In conclusion, these results do not provide any evidence for the presence of NV genome sequences in bottled waters.


2021 ◽  
Vol 32 (4) ◽  
pp. 637-644
Author(s):  
Jamal Nasser Saleh Al-maamari ◽  
Mahardian Rahmadi ◽  
Sisca Melani Panggono ◽  
Devita Ardina Prameswari ◽  
Eka Dewi Pratiwi ◽  
...  

Abstract Objectives The study aimed to determine the effect of quercetin on the expression of primary regulator gene involved in lipogenesis and triglycerides synthesis in the liver, and the sterol regulatory binding protein-1c (SREBP-1c) mRNA in non-alcoholic fatty liver disease (NAFLD) with a high-fat diet (HFD) model. Methods Fifty-six Balb/c mice were divided into seven groups: standard feed; HFD; HFD and quercetin 50 mg/kg for 28 days; HFD and quercetin 100 mg/kg BW for 28 days; HFD and quercetin 50 mg/kg for 14 days; HFD and quercetin 100 mg/kg for 14 days; HFD and repaired fed for 14 days. Quercetin was administered intraperitoneally. The animals were sacrificed 24 h after the last treatment; the liver was taken for macroscopic, histopathological staining using hematoxylin–eosin and reverse transcription-PCR analysis sample. Results HFD significantly increased the expression of SREBP-1c mRNA; meanwhile, quercetin and repaired feed significantly reduced the expression of SREBP-1c mRNA in the liver. Quercetin at a dose of 50 mg/kg and 100 mg/kg also improved liver cells’ pathological profile in high-fat diet NAFLD. Conclusions The present study suggests that quercetin has an inhibitory effect on SREBP-1c expression and improved liver pathology in NAFLD mice.


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