scholarly journals Iron Requirement for Mn(II) Oxidation by Leptothrix discophora SS-1

2008 ◽  
Vol 75 (5) ◽  
pp. 1229-1235 ◽  
Author(s):  
Iman A. El Gheriany ◽  
Daniela Bocioaga ◽  
Anthony G. Hay ◽  
William C. Ghiorse ◽  
Michael L. Shuler ◽  
...  
Keyword(s):  
Complex Formation ◽  
Temporal Variations ◽  
Iron Limitation ◽  
Gene Transcript ◽  
Cellular Functions ◽  
Transcript Levels ◽  
Leptothrix Discophora ◽  
Geochemical Cycling ◽  
Iron Requirement

ABSTRACT A common form of biocatalysis of Mn(II) oxidation results in the formation of biogenic Mn(III, IV) oxides and is a key reaction in the geochemical cycling of Mn. In this study, we grew the model Mn(II)-oxidizing bacterium Leptothrix discophora SS-1 in media with limited iron (0.1 μM iron/5.8 mM pyruvate) and sufficient iron (0.2 μM iron/5.8 mM pyruvate). The influence of iron on the rate of extracellular Mn(II) oxidation was evaluated. Cultures in which cell growth was limited by iron exhibited reduced abilities to oxidize Mn(II) compared to cultures in medium with sufficient iron. While the extracellular Mn(II)-oxidizing factor (MOF) is thought to be a putative multicopper oxidase, Mn(II) oxidation in the presence of zero added Cu(II) was detected and the decrease in the observed Mn(II) oxidation rate in iron-limited cultures was not relieved when the medium was supplemented with Cu(II). The decline of Mn(II) oxidation under iron-limited conditions was not accompanied by siderophore production and is unlikely to be an artifact of siderophore complex formation with Mn(III). The temporal variations in mofA gene transcript levels under conditions of limited and abundant iron were similar, indicating that iron limitation did not interfere with the transcription of the mofA gene. Our quantitative PCR results provide a step forward in understanding the regulation of Mn(II) oxidation. The mechanistic role of iron in Mn(II) oxidation is uncertain; the data are consistent with a direct requirement for iron as a component of the MOF or an indirect effect of iron resulting from the limitation of one of many cellular functions requiring iron.

scholarly journals The role of hepatocyte nuclear factor 4α in regulating mouse hepatic anticoagulation and fibrinolysis gene transcript levels

2010 ◽  
Vol 8 (12) ◽  
pp. 2839-2841 ◽  
Author(s):  
H. SAFDAR ◽  
Y. INOUE ◽  
G. H. VAN PUIJVELDE ◽  
P. H. REITSMA ◽  
B. J. M. VAN VLIJMEN
Keyword(s):  
Gene Transcript ◽  
Nuclear Factor ◽  
Hepatocyte Nuclear Factor ◽  
Transcript Levels ◽  
Hepatocyte Nuclear Factor 4Α

scholarly journals Potential Role of Circulating Endoglin in Hypertension via the Upregulated Expression of BMP4

Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 988 ◽  
Author(s):  
Eunate Gallardo-Vara ◽  
Luis Gamella-Pozuelo ◽  
Lucía Perez-Roque ◽  
José L. Bartha ◽  
Irene Garcia-Palmero ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cardiovascular Diseases ◽  
Pregnant Women ◽  
Plasma Levels ◽  
Molecular Mechanisms ◽  
Proteolytic Processing ◽  
Gene Transcript ◽  
Multisystem Disorder ◽  
Transcript Levels

Endoglin is a membrane glycoprotein primarily expressed by the vascular endothelium and involved in cardiovascular diseases. Upon the proteolytic processing of the membrane-bound protein, a circulating form of endoglin (soluble endoglin, sEng) can be released, and high levels of sEng have been observed in several endothelial-related pathological conditions, where it appears to contribute to endothelial dysfunction. Preeclampsia is a multisystem disorder of high prevalence in pregnant women characterized by the onset of high blood pressure and associated with increased levels of sEng. Although a pathogenic role for sEng involving hypertension has been reported in several animal models of preeclampsia, the exact molecular mechanisms implicated remain to be identified. To search for sEng-induced mediators of hypertension, we analyzed the protein secretome of human endothelial cells in the presence of sEng. We found that sEng induces the expression of BMP4 in endothelial cells, as evidenced by their proteomic signature, gene transcript levels, and BMP4 promoter activity. A mouse model of preeclampsia with high sEng plasma levels (sEng+) showed increased transcript levels of BMP4 in lungs, stomach, and duodenum, and increased circulating levels of BMP4, compared to those of control animals. In addition, after crossing female wild type with male sEng+ mice, hypertension appeared 18 days after mating, coinciding with the appearance of high plasma levels of BMP4. Also, serum levels of sEng and BMP4 were positively correlated in pregnant women with and without preeclampsia. Interestingly, sEng-induced arterial pressure elevation in sEng+ mice was abolished in the presence of the BMP4 inhibitor noggin, suggesting that BMP4 is a downstream mediator of sEng. These results provide a better understanding on the role of sEng in the physiopathology of preeclampsia and other cardiovascular diseases, where sEng levels are increased.

The role of exon II HTR2A transcript isoforms in the development of mental pathologies and antipsychotic therapy prognosis

2020 ◽  
pp. 24-26
Author(s):  
М.Н. Грунина ◽  
А.М. Заботина ◽  
А.С. Журавлев ◽  
Р.Ф. Насырова ◽  
А.Е. Тараскина
Keyword(s):  
Genetic Variant ◽  
Therapy Outcome ◽  
Gene Transcript ◽  
Antipsychotic Therapy ◽  
Transcript Isoforms ◽  
Alternative Isoforms ◽  
Htr2a Gene

Психические расстройства ассоциированы с нарушением паттерна изоформ транскриптов экзона II гена HTR2A за счет преобладания альтернативной изоформы Е2-. При этом высокий уровень экспрессии изоформы Е2- ассоциирован с благоприятным прогнозом антипсихотической терапии. The aim of the study was to analyze the role of exon II HTR2A gene transcript isoforms and rs6311 genetic variant in the development of mental pathologies and antipsychotic therapy prognosis. Alternative isoforms of exon II HTR2A are associated with the development of mental pathologies and is applicable to predict antipsychotic therapy outcome.

The Role of microRNAs in the Viral Infections

2019 ◽  
Vol 24 (39) ◽  
pp. 4659-4667 ◽  
Author(s):  
Mona Fani ◽  
Milad Zandi ◽  
Majid Rezayi ◽  
Nastaran Khodadad ◽  
Hadis Langari ◽  
...  
Keyword(s):  
Viral Infections ◽  
Rna Viruses ◽  
Regulation Of Gene Expression ◽  
Molecular Structures ◽  
Main Function ◽  
Cellular Functions ◽  
Viral Genes ◽  
Non Coding Rnas ◽  
Post Transcriptional Regulation

MicroRNAs (miRNAs) are non-coding RNAs with 19 to 24 nucleotides which are evolutionally conserved. MicroRNAs play a regulatory role in many cellular functions such as immune mechanisms, apoptosis, and tumorigenesis. The main function of miRNAs is the post-transcriptional regulation of gene expression via mRNA degradation or inhibition of translation. In fact, many of them act as an oncogene or tumor suppressor. These molecular structures participate in many physiological and pathological processes of the cell. The virus can also produce them for developing its pathogenic processes. It was initially thought that viruses without nuclear replication cycle such as Poxviridae and RNA viruses can not code miRNA, but recently, it has been proven that RNA viruses can also produce miRNA. The aim of this articles is to describe viral miRNAs biogenesis and their effects on cellular and viral genes.

MicroRNAs as Biomarker for Breast Cancer

2020 ◽  
Vol 20 (10) ◽  
pp. 1597-1610 ◽  
Author(s):  
Taru Aggarwal ◽  
Ridhima Wadhwa ◽  
Riya Gupta ◽  
Keshav Raj Paudel ◽  
Trudi Collet ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Association Studies ◽  
Large Family ◽  
Breast Cancer Diagnosis ◽  
Cell Multiplication ◽  
Cell Physiology ◽  
Gene Transcript ◽  
Genome Wide Association Studies ◽  
Non Coding Rnas

Regardless of advances in detection and treatment, breast cancer affects about 1.5 million women all over the world. Since the last decade, genome-wide association studies (GWAS) have been extensively conducted for breast cancer to define the role of miRNA as a tool for diagnosis, prognosis and therapeutics. MicroRNAs are small, non-coding RNAs that are associated with the regulation of key cellular processes such as cell multiplication, differentiation, and death. They cause a disturbance in the cell physiology by interfering directly with the translation and stability of a targeted gene transcript. MicroRNAs (miRNAs) constitute a large family of non-coding RNAs, which regulate target gene expression and protein levels that affect several human diseases and are suggested as the novel markers or therapeutic targets, including breast cancer. MicroRNA (miRNA) alterations are not only associated with metastasis, tumor genesis but also used as biomarkers for breast cancer diagnosis or prognosis. These are explained in detail in the following review. This review will also provide an impetus to study the role of microRNAs in breast cancer.

scholarly journals Carcinoma-associated fibroblasts derived exosomes modulate breast cancer cell stemness through exonic circHIF1A by miR-580-5p in hypoxic stress

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yanxia Zhan ◽  
Junxian Du ◽  
Zhihui Min ◽  
Li Ma ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Stem Cell ◽  
Breast Cancer Cells ◽  
Hypoxic Stress ◽  
Cellular Functions ◽  
Breast Cancer Therapy ◽  
Array Analysis ◽  
Cancer Stroma ◽  
Carcinoma Associated Fibroblasts

AbstractHypoxia is a common phenomenon in solid tumors. The roles of exosomes from hypoxic breast cancer stroma are less studied. So, the study was aimed to investigate the role of exosomes from hypoxic cancer-associated fibroblasts (CAFs) cells in breast cancer. The circRNA array analysis was performed to screen differential expressed circRNAs between hypoxic and normoxic CAFs exosomes. Candidate circHIF1A (circ_0032138) was screened out and it was confirmed that circHIF1A was up-regulated in the exosomes from hypoxic CAFs and their exosomes. Through investigating cellular functions including cell proliferation and stem cell features, it was demonstrated that hypoxic CAFs exosomes transferred circHIF1A into breast cancer cells, which played an important role in cancer stem cell properties sponging miR-580-5p by regulating CD44 expression. In a summary, circHIF1A from hypoxic CAFs exosomes played an important role in stem cell properties of breast cancer. CircHIF1A may act as a target molecule of breast cancer therapy.

Enantioselective Effect of Flutriafol on Growth, Deoxynivalenol Production, and TRI Gene Transcript Levels in Fusarium graminearum

2021 ◽  
Vol 69 (5) ◽  
pp. 1684-1692
Author(s):  
Chaofeng Li ◽  
Shuai Fan ◽  
Yan Wen ◽  
Zhenchao Tan ◽  
Chenglan Liu
Keyword(s):  
Fusarium Graminearum ◽  
Gene Transcript ◽  
Transcript Levels

scholarly journals CO2 dynamics and heterogeneity in a cave atmosphere: role of ventilation patterns and airflow pathways

2021 ◽  
Author(s):  
Lovel Kukuljan ◽  
Franci Gabrovšek ◽  
Matthew D. Covington ◽  
Vanessa E. Johnston
Keyword(s):  
Temporal Variations ◽  
Observation Point ◽  
Spatially Distributed ◽  
Combined Action ◽  
Karst Systems ◽  
The Relationship ◽  
Co2 Dynamics ◽  
Global Carbon

AbstractUnderstanding the dynamics and distribution of CO2 in the subsurface atmosphere of carbonate karst massifs provides important insights into dissolution and precipitation processes, the role of karst systems in the global carbon cycle, and the use of speleothems for paleoclimate reconstructions. We discuss long-term microclimatic observations in a passage of Postojna Cave, Slovenia, focusing on high spatial and temporal variations of pCO2. We show (1) that the airflow through the massif is determined by the combined action of the chimney effect and external winds and (2) that the relationship between the direction of the airflow, the geometry of the airflow pathways, and the position of the observation point explains the observed variations of pCO2. Namely, in the terminal chamber of the passage, the pCO2 is low and uniform during updraft, when outside air flows to the site through a system of large open galleries. When the airflow reverses direction to downdraft, the chamber is fed by inlets with diverse flow rates and pCO2, which enter via small conduits and fractures embedded in a CO2-rich vadose zone. If the spatial distribution of inlets and outlets produces minimal mixing between low and high pCO2 inflows, high and persistent gradients in pCO2 are formed. Such is the case in the chamber, where vertical gradients of up to 1000 ppm/m are observed during downdraft. The results presented in this work provide new insights into the dynamics and composition of the subsurface atmosphere and demonstrate the importance of long-term and spatially distributed observations.

scholarly journals The Role of Ceramide Metabolism and Signaling in the Regulation of Mitophagy and Cancer Therapy

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2475
Author(s):  
Megan Sheridan ◽  
Besim Ogretmen
Keyword(s):  
Cancer Therapy ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Cancer Cell Proliferation ◽  
Bioactive Lipids ◽  
Cellular Functions ◽  
Proliferation Response ◽  
Ceramide Synthases

Sphingolipids are bioactive lipids responsible for regulating diverse cellular functions such as proliferation, migration, senescence, and death. These lipids are characterized by a long-chain sphingosine backbone amide-linked to a fatty acyl chain with variable length. The length of the fatty acyl chain is determined by specific ceramide synthases, and this fatty acyl length also determines the sphingolipid’s specialized functions within the cell. One function in particular, the regulation of the selective autophagy of mitochondria, or mitophagy, is closely regulated by ceramide, a key regulatory sphingolipid. Mitophagy alterations have important implications for cancer cell proliferation, response to chemotherapeutics, and mitophagy-mediated cell death. This review will focus on the alterations of ceramide synthases in cancer and sphingolipid regulation of lethal mitophagy, concerning cancer therapy.

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