scholarly journals Medicago truncatula Natural Resistance-Associated Macrophage Protein1 Is Required for Iron Uptake by Rhizobia-Infected Nodule Cells

2015 ◽  
Vol 168 (1) ◽  
pp. 258-272 ◽  
Author(s):  
Manuel Tejada-Jiménez ◽  
Rosario Castro-Rodríguez ◽  
Igor Kryvoruchko ◽  
M. Mercedes Lucas ◽  
Michael Udvardi ◽  
...  
Keyword(s):  
Medicago Truncatula ◽  
Iron Uptake ◽  
Natural Resistance ◽  
Infected Nodule

Solute carrier 11a1 (Slc11a1; formerly Nramp1) regulates metabolism and release of iron acquired by phagocytic, but not transferrin-receptor-mediated, iron uptake

2002 ◽  
Vol 363 (1) ◽  
pp. 89-94 ◽  
Author(s):  
Victoriano MULERO ◽  
Susan SEARLE ◽  
Jenefer M. BLACKWELL ◽  
Jeremy H. BROCK
Keyword(s):  
Iron Uptake ◽  
Interferon Γ ◽  
Natural Resistance ◽  
Null Alleles ◽  
Iron Release ◽  
Wild Type ◽  
Bivalent Cation ◽  
Insoluble Form ◽  
Solute Carrier ◽  
Macrophage Protein

Solute carrier 11a1 (Slc11a1; formerly Nramp1; where Nramp stands for natural-resistance-associated macrophage protein) is a proton/bivalent cation antiporter that localizes to late endosomes/lysosomes and controls resistance to pathogens. In the present study the role of Slc11a1 in iron turnover is examined in macrophages transfected with Slc11a1Gly169 (wild-type) or Slc11a1Asp169 (mutant = functional null) alleles. Following direct acquisition of transferrin (Tf)-bound iron via the Tf receptor, iron uptake and release was equivalent in wild-type and mutant macrophages and was not influenced by interferon-γ/lipopolysaccharide activation. Following phagocytosis of [59Fe]Tf—anti-Tf immune complexes, iron uptake was equivalent and up-regulated similarly with activation, but intracellular distribution was markedly different. In wild-type macrophages most iron was in the soluble (60%) rather than insoluble (12%) fraction, with 28% ferritin (Ft)-bound. With activation, the soluble component increased to 82% at the expense of Ft-bound iron (< 5%). In mutant macrophages, 40–50% of iron was in insoluble form, 50–60% was soluble and < 5% was Ft-bound. Western-blot analysis confirmed failure of mutant macrophages to degrade complexes 24h after phagocytic uptake. Confocal microscopy showed that complexes were within lysosome-associated membrane protein 1-positive vesicles in wild-type and mutant macrophages at 30min and 24h, implying failure in the degradative process in mature phagosomes in mutant macrophages. NO-mediated iron release was 2.4-fold higher in activated wild-type macrophages compared with mutant macrophages. Overall, our data suggest that iron acquired by phagocytosis and degradation is retained within the phagosomal compartment in wild-type macrophages, and that NO triggers iron release by direct secretion of phagosomal contents rather than via the cytoplasm.

scholarly journals Transcription of ENOD8 in Medicago truncatula Nodules Directs ENOD8 Esterase to Developing and Mature Symbiosomes

2008 ◽  
Vol 21 (4) ◽  
pp. 404-410 ◽  
Author(s):  
Laurent Coque ◽  
Purnima Neogi ◽  
Catalina Pislariu ◽  
Kimberly A. Wilson ◽  
Christina Catalano ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Medicago Truncatula ◽  
Sinorhizobium Meliloti ◽  
Immunoblot Analysis ◽  
Nodule Formation ◽  
Nitrogenous Compounds ◽  
Symbiosome Membrane ◽  
The Matrix ◽  
And Function ◽  
Infected Nodule

In Medicago truncatula nodules, the soil bacterium Sinorhizobium meliloti reduces atmospheric dinitrogen into nitrogenous compounds that the legume uses for its own growth. In nitrogen-fixing nodules, each infected cell contains symbiosomes, which include the rhizobial cell, the symbiosome membrane surrounding it, and the matrix between the bacterium and the symbiosome membrane, termed the symbiosome space. Here, we describe the localization of ENOD8, a nodule-specific esterase. The onset of ENOD8 expression occurs at 4 to 5 days postinoculation, before the genes that support the nitrogen fixation capabilities of the nodule. Expression of an ENOD8 promoter–gusA fusion in nodulated hairy roots of composite transformed M. truncatula plants indicated that ENOD8 is expressed from the proximal end of interzone II to III to the proximal end of the nodules. Confocal immunomicroscopy using an ENOD8-specific antibody showed that the ENOD8 protein was detected in the same zones. ENOD8 protein was localized in the symbiosome membrane or symbiosome space around the bacteroids in the infected nodule cells. Immunoblot analysis of fractionated symbiosomes strongly suggested that ENOD8 protein was found in the symbiosome membrane and symbiosome space, but not in the bacteroid. Determining the localization of ENOD8 protein in the symbiosome is a first step in understanding its role in symbiosome membrane and space during nodule formation and function.

Heterologous expression, functional characterization and localization of two isoforms of the monkey iron transporter Nramp2

2000 ◽  
Vol 349 (1) ◽  
pp. 289-297 ◽  
Author(s):  
Li ZHANG ◽  
Timothy LEE ◽  
Yue WANG ◽  
Tuck W. SOONG
Keyword(s):  
Amino Acid ◽  
Subcellular Localization ◽  
Tissue Distribution ◽  
Iron Uptake ◽  
Functional Characterization ◽  
Amino Acid Level ◽  
Natural Resistance ◽  
C Terminus ◽  
Macrophage Protein ◽  
Responsive Element

Natural resistance-associated macrophage protein 2 (Nramp2) has been suggested to be involved in transferrin-independent iron uptake. Two isoforms of the Nramp2 gene generated by alternative splicing of the 3ʹ exons were identified in mouse, rat and human, but it is unclear if they perform distinct functions. To rationalize our previous work, which indicated an increase in iron deposition in a Parkinsonian monkey brain, two monkey Nramp2 isoforms were isolated for a comparative study to assess their relative iron-uptake abilities, tissue distribution and subcellular localization. The monkey Nramp2 isoforms, 2a and 2b, exhibit approx. 98% identity at the amino acid level when compared with the human homologues. The Nramp2a transcript contains a canonical iron-responsive element (IRE), whereas that of Nramp2b lacks the IRE motif in the 3ʹ untranslated region. By reverse transcriptase (RT)-PCR, the mRNAs of both isoforms were detected in all tissues examined. The amino acid differences at the C-terminus neither affected the protein expression levels in HEK-293T and COS-7 cells nor altered the subcellular localization and tissue distribution of the isoforms. Similar levels of iron uptake were detected in the HEK-293T cells transfected with either the Nramp2a or 2b gene, and a reduction of iron from the ferric (Fe3+) to the ferrous (Fe2+) state is necessary before transport can take place. However, this transferrin-independent uptake of iron into the cells is not a Ca2+-dependent process.

The Natural Resistance-Associated Macrophage Protein from the Protozoan ParasitePerkinsus marinusMediates Iron Uptake

Biochemistry ◽  
2011 ◽  
Vol 50 (29) ◽  
pp. 6340-6355 ◽  
Author(s):  
Zhuoer Lin ◽  
José-Antonio Fernández-Robledo ◽  
Mathieu F. M. Cellier ◽  
Gerardo R. Vasta
Keyword(s):  
Iron Uptake ◽  
Natural Resistance ◽  
Macrophage Protein

scholarly journals Iron uptake and Nramp2/DMT1/DCT1 in human bronchial epithelial cells

2002 ◽  
Vol 282 (5) ◽  
pp. L987-L995 ◽  
Author(s):  
Xinchao Wang ◽  
Andrew J. Ghio ◽  
Funmei Yang ◽  
Kevin G. Dolan ◽  
Michael D. Garrick ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Iron Uptake ◽  
Airway Epithelial Cells ◽  
Natural Resistance ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Metal Exposure ◽  
Airway Epithelial ◽  
Divalent Metal Transporter 1 ◽  
Peripheral Tissues

The capacity of natural resistance-associated macrophage protein-2 [Nramp2; also called divalent metal transporter-1 (DMT1) and divalent cation transporter-1 (DCT1)] to transport iron and its ubiquitous expression make it a likely candidate for transferrin-independent uptake of iron in peripheral tissues. We tested the hypothesis that non-transferrin-bound iron uptake by airway epithelial cells is associated with Nramp2/DMT1/DCT1 and that exposure to iron can increase Nramp2/DMT1/DCT1 mRNA and protein expression and transport of this metal. Exposure of BEAS-2B cells to ferric ammonium citrate (FAC) resulted in a decrease in Fe3+concentration in the supernatant that was dependent on time and initial iron concentration. In the presence of internalized calcein, FAC quenched the fluorescent signal, indicating intracellular transport of the metal. The Nramp2/DMT1/DCT1 mRNA isoform without an iron-response element (IRE) increased with exposure of BEAS-2B cells to FAC. RT-PCR demonstrated no change in the mRNA for the isoform with an IRE. Similarly, Western blot analysis for the isoform without an IRE confirmed an increased expression of this protein after FAC exposure, whereas the isoform with an IRE exhibited no change. Finally, immunohistochemistry revealed an increase in the isoform without an IRE in the rat lung epithelium after instillation of FAC. Comparable to mRNA and protein increases, iron transport was elevated after pretreatment of BEAS-2B cells with iron-containing compounds. We conclude that airway epithelial cells increase mRNA and expression of the Nramp2/DMT1/DCT1 without an IRE after exposure to iron. The increase results in an elevated transport of iron and its probable detoxification by these cells.

Medicago truncatula increases its iron-uptake mechanisms in response to volatile organic compounds produced by Sinorhizobium meliloti

2013 ◽  
Vol 58 (6) ◽  
pp. 579-585 ◽  
Author(s):  
Ma. del Carmen Orozco-Mosqueda ◽  
Lourdes I. Macías-Rodríguez ◽  
Gustavo Santoyo ◽  
Rodolfo Farías-Rodríguez ◽  
Eduardo Valencia-Cantero
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Medicago Truncatula ◽  
Iron Uptake ◽  
Sinorhizobium Meliloti ◽  
Volatile Organic ◽  
Uptake Mechanisms

Isolation of Multiple Types of Plasminogen Activator Inhibitors from Vascular Smooth Muscle Cells

1989 ◽  
Vol 61 (03) ◽  
pp. 517-521 ◽  
Author(s):  
Walter E Laug ◽  
Ruedi Aebersold ◽  
Ambrose Jong ◽  
Willian Rideout ◽  
Barbara L Bergman ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Affinity Purification ◽  
Muscle Cells ◽  
Exchange Chromatography ◽  
Natural Resistance ◽  
Protease Nexin ◽  
Pai 1

SummaryLarge arteries have a natural resistance to tumor cell invasion thought to be due to the production of protease inhibitors. Vascular smooth muscle cells (VSMC) representing the major cellular part of arteries were isolated from human aortas and grown in tissue culture. These cells were found to produce large amounts of inhibitors of plasminogen activators (PA). Fractionation of VSMC-conditioned medium by heparin-affigel chromatography separated three immunologically and functionally distinct PA inhibitors (PAI), namely PAI-1, PAI-2 and protease-nexin I. The three inhibitors were characterized by functional assays and immunoblotting. PA inhibitor 2 (PAI-2) had little affinity for heparin, whereas PA inhibitor 1 (PAI-l) bound to heparin and was eluted from the column at NaCl concentrations of 0. 1 to 0.35 M. Protease-nexin I, eluted at NaCl concentrations of 0.5 M and higher. Most of the PAI-1 was present in the latent, inactive form. PAI-1 was further purified by ion exchange chromatography on a Mono-Q column. Partial sequencing of the purified PAI-1 confirmed its nature by matching completely with the sequence deduced from the cDNA nucleotide sequence of endothelial cell PAI-1. Thus, human VSMC produce all three presently known PAI and these can be separated in a single heparin affinity purification step.

Evaluation of clinical efficacy of Derinat® in form of spray in practice of district therapist

2019 ◽  
Vol 1 (9) ◽  
pp. 38-46
Author(s):  
A. P. Babkin ◽  
A. A. Zuikova ◽  
O. N. Krasnorutskaya ◽  
Yu. A. Kotova ◽  
D. Yu. Bugrimov ◽  
...  
Keyword(s):  
Clinical Efficacy ◽  
Respiratory Diseases ◽  
Viral Infections ◽  
Pharmacological Action ◽  
The Body ◽  
Natural Resistance ◽  
Acute Respiratory Diseases ◽  
T Helpers ◽  
T Killers ◽  
Stimulation Of

The widespread worldwide spread of acute respiratory diseases is an urgent problem in health care. Expressed polyetiology of respiratory diseases does not allow to limit the use of specific vaccine preparations and dictates the need to use to combat them a variety of non-specific means that stimulate the natural resistance of the human body. The main pharmacological action of sodium deoxyribonucleate is the stimulation of phagocytic activity of T-helpers and T-killers, increasing the functional activity of neutrophils and monocytes/ macrophages, providing regeneration and repair processes in the epithelial component of antiviral protection of the body. Based on the above, the study of the clinical efficacy of Derinat® in the form of spray in the treatment of acute respiratory viral infections is relevant.

Evaluasi Awal Ketahanan Beberapa Kultivar Talas Terhadap Serangan Kumbang Talas, Papuana spp. (Coleoptera : Scarabaeidae)

Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Alexander Yaku
Keyword(s):  
South Pacific ◽  
Insect Behavior ◽  
Natural Resistance ◽  
The South ◽  
White Colour ◽  
Selection Of

Taro beetles, Papuana spp., (Coleoptera: Scarabaeidae) are pests of taro (Colozasia esculenta) and a number of other plants in the South Pacific regions including Papua. The pest have become serious threat for taro farmers because it damage corm resulting in the loss of production. To control the taro beetle, 104 taro cultivars were evaluated for their natural resistance. The experiment was conducted in the Unipa Farm located in East Amban. Results of research shows that there are three cultivars being highly resistance and 36 cultivars being only resistance. The taro with white colour of corm flesh seems to be a non-preference factor that alter insect behavior, resulting in the selection of alternate taro cultivars.

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