Ion transporters in the root nodule of Medicago truncatula: potassium transporters

Abstract book of the 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology" PLAMIC2020 ◽

10.28983/plamic2020.071 ◽

2020 ◽

Author(s):

E. E. Fedorova ◽

N. A. Trifonova

Keyword(s):

Plasma Membrane ◽

Medicago Truncatula ◽

Root Nodule ◽

Ion Transporters ◽

Potassium Loss ◽

Transporter Proteins ◽

Potassium Transporters ◽

Infected Cells

The transporter proteins were mistargeted and partly depleted from plasma membrane of mature infected cells, this phenomenon may contribute to the potassium loss by symbiosomes during their development and senescence.

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Potassium content diminishes in infected cells of Medicago truncatula nodules due to the mislocation of channels MtAKT1 and MtSKOR/GORK

Journal of Experimental Botany ◽

10.1093/jxb/eraa508 ◽

2020 ◽

Author(s):

Elena E Fedorova ◽

Teodoro Coba de la Peña ◽

Victoria Lara-Dampier ◽

Natalia A Trifonova ◽

Olga Kulikova ◽

...

Keyword(s):

Medicago Truncatula ◽

Root Nodule ◽

Root Nodules ◽

Phylogenetic Analyses ◽

Gene Copy ◽

Gene Localization ◽

K Channel ◽

Infected Cells ◽

Plant Ion Channels ◽

Mature Nodule

Root nodule-infected cells have defects in K+ balance, as compared with non-infected cells, probably due to variation in the location of K+ channel proteins MtAKT1 and MtSKOR/GORK. Abstract Rhizobia establish a symbiotic relationship with legumes that results in the formation of root nodules, where bacteria encapsulated by a membrane of plant origin (symbiosomes), convert atmospheric nitrogen into ammonia. Nodules are more sensitive to ionic stresses than the host plant itself. We hypothesize that such a high vulnerability might be due to defects in ion balance in the infected tissue. Low temperature SEM (LTSEM) and X-ray microanalysis of Medicago truncatula nodules revealed a potassium (K+) decrease in symbiosomes and vacuoles during the life span of infected cells. To clarify K+ homeostasis in the nodule, we performed phylogenetic and gene expression analyses, and confocal and electron microscopy localization of two key plant Shaker K+ channels, AKT1 and SKOR/GORK. Phylogenetic analyses showed that the genome of some legume species, including the Medicago genus, contained one SKOR/GORK and one AKT1 gene copy, while other species contained more than one copy of each gene. Localization studies revealed mistargeting and partial depletion of both channels from the plasma membrane of M. truncatula mature nodule-infected cells that might compromise ion transport. We propose that root nodule-infected cells have defects in K+ balance due to mislocation of some plant ion channels, as compared with non-infected cells. The putative consequences are discussed.

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Formin-mediated bridging of cell wall, plasma membrane, and cytoskeleton in symbiotic infections of Medicago truncatula

Current Biology ◽

10.1016/j.cub.2021.04.002 ◽

2021 ◽

Author(s):

Pengbo Liang ◽

Clara Schmitz ◽

Beatrice Lace ◽

Franck Anicet Ditengou ◽

Chao Su ◽

...

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Medicago Truncatula

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Regulation and activity of CaTrk1, CaAcu1 and CaHak1, the three plasma membrane potassium transporters in Candida albicans

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/j.bbamem.2020.183486 ◽

2021 ◽

Vol 1863 (1) ◽

pp. 183486

Author(s):

Francisco J. Ruiz-Castilla ◽

Jan Bieber ◽

Gabriel Caro ◽

Carmen Michán ◽

Hana Sychrova ◽

...

Keyword(s):

Candida Albicans ◽

Plasma Membrane ◽

Potassium Transporters

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Retention of adenovirus E19 glycoprotein in the endoplasmic reticulum is essential to its ability to block antigen presentation.

Journal of Experimental Medicine ◽

10.1084/jem.174.6.1629 ◽

1991 ◽

Vol 174 (6) ◽

pp. 1629-1637 ◽

Cited By ~ 69

Author(s):

J H Cox ◽

J R Bennink ◽

J W Yewdell

Keyword(s):

Endoplasmic Reticulum ◽

Plasma Membrane ◽

Antigen Presentation ◽

Viral Proteins ◽

Genetically Engineered ◽

Class I ◽

Wild Type ◽

Histocompatibility Complex ◽

Infected Cells ◽

Lumenal Domain

The E3/19K glycoprotein of adenovirus functions to diminish recognition of adenovirus-infected cells by major histocompatibility complex class I-restricted cytotoxic T lymphocytes (CTLs) by binding intracellular class I molecules and preventing them from reaching the plasma membrane. In the present study we have characterized the nature of the interaction between E3/19K and the H-2Kd (Kd) molecule. An E3/19K molecule genetically engineered to terminate six residues from its normal COOH terminus (delta E19), was found to associate with Kd in a manner indistinguishable from wild-type E3/19K. Unlike E3/19K, however, delta E19 was transported through the Golgi complex to the plasma membrane, where it could be detected biochemically and immunocytochemically using a monoclonal antibody specific for the lumenal domain of E3/19K. Importantly, delta E19 also differed from E3/19K in being unable to prevent the presentation of Kd-restricted viral proteins to CTLs. This is unlikely to be due to delta E19 having a lower avidity for Kd than E3/19K, since delta E19 was able to compete with E3/19K for Kd binding, both physically, and functionally in nullifying the E3/19K blockade of antigen presentation. These findings indicate that the ability of E3/19K to block antigen presentation is due solely to its ability to retain newly synthesized class I molecules in the endoplasmic reticulum.

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Plasma membrane damage causes NLRP3 activation and pyroptosis during Mycobacterium tuberculosis infection

10.1101/747014 ◽

2019 ◽

Author(s):

Kai S. Beckwith ◽

Marianne S. Beckwith ◽

Sindre Ullmann ◽

Ragnhild Sætra ◽

Haelin Kim ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Plasma Membrane ◽

Membrane Damage ◽

Common Mechanism ◽

Mycobacterium Tuberculosis Infection ◽

Plasma Membrane Damage ◽

Cytosolic Side ◽

Infected Cells ◽

Mediated Contact ◽

Spread Of Infection

AbstractMycobacterium tuberculosis (Mtb) is a major global health problem and causes extensive cytotoxicity in patient cells and tissues. Here we define an NLRP3, caspase-1 and gasdermin D-mediated pathway to pyroptosis in human monocytes following exposure to Mtb. We demonstrate an ESX-1 mediated, contact-induced plasma membrane (PM) damage response that occurs during phagocytosis or from the cytosolic side of the PM after phagosomal rupture in Mtb infected cells. This PM injury in turn causes K+ efflux and activation of NLRP3 dependent IL-1β release and pyroptosis, facilitating the spread of Mtb to neighbouring cells. Further we reveal a dynamic interplay of pyroptosis with ESCRT-mediated PM repair. Collectively, these findings reveal a novel mechanism for pyroptosis and spread of infection acting through dual PM disturbances both during and after phagocytosis. We also highlight dual PM damage as a common mechanism utilized by other NLRP3 activators that have previously been shown to act through lysosomal damage.Graphical abstract

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The Equine Herpesvirus 1 US2 Homolog Encodes a Nonessential Membrane-Associated Virion Component

Journal of Virology ◽

10.1128/jvi.73.4.3430-3437.1999 ◽

1999 ◽

Vol 73 (4) ◽

pp. 3430-3437 ◽

Cited By ~ 27

Author(s):

Alexandra Meindl ◽

Nikolaus Osterrieder

Keyword(s):

Amino Acids ◽

Plasma Membrane ◽

Secretory Pathway ◽

Fluorescent Protein ◽

Viral Envelope ◽

Equine Herpesvirus ◽

Equine Herpesvirus 1 ◽

Amino Terminal ◽

Infected Cells ◽

Herpesvirus 1

ABSTRACT Experiments were conducted to analyze the equine herpesvirus 1 (EHV-1) gene 68 product which is encoded by the EHV-1 US2 homolog. An antiserum directed against the amino-terminal 206 amino acids of the EHV-1 US2 protein specifically detected a protein with an M r of 34,000 in cells infected with EHV-1 strain RacL11. EHV-1 strain Ab4 encodes a 44,000-M r Us2 protein, whereas vaccine strain RacH, a high-passage derivative of RacL11, encodes a 31,000-M r Us2 polypeptide. Irrespective of its size, the US2 protein was incorporated into virions. The EHV-1 US2 protein localized to membrane and nuclear fractions of RacL11-infected cells and to the envelope fraction of purified virions. To monitor intracellular trafficking of the protein, the green fluorescent protein (GFP) was fused to the carboxy terminus of the EHV-1 US2 protein or to a truncated US2 protein lacking a stretch of 16 hydrophobic amino acids at the extreme amino terminus. Both fusion proteins were detected at the plasma membrane and accumulated in the vicinity of nuclei of transfected cells. However, trafficking of either GFP fusion protein through the secretory pathway could not be demonstrated, and the EHV-1 US2 protein lacked detectable N- and O-linked carbohydrates. Consistent with the presence of the US2 protein in the viral envelope and plasma membrane of infected cells, a US2-negative RacL11 mutant (L11ΔUS2) exhibited delayed penetration kinetics and produced smaller plaques compared with either wild-type RacL11 or a US2-repaired virus. After infection of BALB/c mice with L11ΔUS2, reduced pathogenicity compared with the parental RacL11 virus and the repaired virus was observed. It is concluded that the EHV-1 US2 protein modulates virus entry and cell-to-cell spread and appears to support sustained EHV-1 replication in vivo.

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Biarsenical Labeling of Vesicular Stomatitis Virus Encoding Tetracysteine-Tagged M Protein Allows Dynamic Imaging of M Protein and Virus Uncoating in Infected Cells

Journal of Virology ◽

10.1128/jvi.01668-08 ◽

2009 ◽

Vol 83 (6) ◽

pp. 2611-2622 ◽

Cited By ~ 42

Author(s):

Subash C. Das ◽

Debasis Panda ◽

Debasis Nayak ◽

Asit K. Pattnaik

Keyword(s):

Plasma Membrane ◽

Vesicular Stomatitis Virus ◽

Matrix Protein ◽

Fluorescent Protein ◽

Dynamic Imaging ◽

Viral Envelope ◽

M Protein ◽

Recombinant Viruses ◽

Infected Cells ◽

Vesicular Stomatitis

ABSTRACT A recombinant vesicular stomatitis virus (VSV-PeGFP-M-MmRFP) encoding enhanced green fluorescent protein fused in frame with P (PeGFP) in place of P and a fusion matrix protein (monomeric red fluorescent protein fused in frame at the carboxy terminus of M [MmRFP]) at the G-L gene junction, in addition to wild-type (wt) M protein in its normal location, was recovered, but the MmRFP was not incorporated into the virions. Subsequently, we generated recombinant viruses (VSV-PeGFP-ΔM-Mtc and VSV-ΔM-Mtc) encoding M protein with a carboxy-terminal tetracysteine tag (Mtc) in place of the M protein. These recombinant viruses incorporated Mtc at levels similar to M in wt VSV, demonstrating recovery of infectious rhabdoviruses encoding and incorporating a tagged M protein. Virions released from cells infected with VSV-PeGFP-ΔM-Mtc and labeled with the biarsenical red dye (ReAsH) were dually fluorescent, fluorescing green due to incorporation of PeGFP in the nucleocapsids and red due to incorporation of ReAsH-labeled Mtc in the viral envelope. Transport and subsequent association of M protein with the plasma membrane were shown to be independent of microtubules. Sequential labeling of VSV-ΔM-Mtc-infected cells with the biarsenical dyes ReAsH and FlAsH (green) revealed that newly synthesized M protein reaches the plasma membrane in less than 30 min and continues to accumulate there for up to 2 1/2 hours. Using dually fluorescent VSV, we determined that following adsorption at the plasma membrane, the time taken by one-half of the virus particles to enter cells and to uncoat their nucleocapsids in the cytoplasm is approximately 28 min.

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IFITM proteins that restrict the early stages of respiratory virus infection do not influence late-stage replication

Journal of Virology ◽

10.1128/jvi.00837-21 ◽

2021 ◽

Author(s):

Tina Meischel ◽

Svenja Fritzlar ◽

Fernando Villalon-Letelier ◽

Melkamu B. Tessema ◽

Andrew G. Brooks ◽

...

Keyword(s):

Plasma Membrane ◽

Antiviral Activity ◽

Influenza A ◽

Respiratory Viruses ◽

Parainfluenza Virus ◽

Early Stages ◽

Infected Cells ◽

Cellular Entry ◽

Overexpression System ◽

Late Stages

Interferon-induced transmembrane (IFITM) proteins inhibit a broad range of enveloped viruses by blocking entry into host cells. We used an inducible overexpression system to investigate if IFITM1, IFITM2 and IFITM3 could modulate early and/or late stages of influenza A virus (IAV) or parainfluenza virus (PIV)-3 infection in human A549 airway epithelial cells. IAV and PIV-3 represent respiratory viruses which utilise distinct cellular entry pathways. We verify entry by endocytosis for IAV, whereas PIV-3 infection was consistent with fusion at the plasma membrane. Following induction prior to infection, all three IFITM proteins restricted the percentage of IAV-infected cells at 8 hours post-infection. In contrast, prior induction of IFITM1 and IFITM2 did not inhibit PIV-3 infection, although a modest reduction was observed with IFITM3. siRNA-mediated knockdown of endogenous IFITM1, IFITM2 and IFITM3 expression, in the presence or absence of pre-treatment with type I interferon, resulted in increased IAV, but not PIV-3, infection. This suggests that while all three IFITMs display antiviral activity against IAV, they do not restrict the early stages of PIV-3 infection. IAV and PIV-3 infection culminates in viral egress through budding at the plasma membrane. Inducible expression of IFITM1, IFITM2 or IFITM3 immediately after infection did not impact titres of infectious virus released from IAV or PIV-3 infected cells. Our findings show that IFITM proteins differentially restrict the early stages of infection of two respiratory viruses with distinct cellular entry pathways, but do not influence the late stages of replication for either virus. IMPORTANCE Interferon-induced transmembrane (IFITM) proteins restrict the initial stages of infection for several respiratory viruses, however their potential to modulate the later stages of virus replication has not been explored. In this study we highlight the utility of an inducible overexpression system to assess the impact of IFITM proteins on either early or late stage replication of two respiratory viruses. We demonstrate antiviral activity by IFITM1, IFITM2 and IFITM3 against influenza A virus (IAV) but not parainfluenza virus (PIV)-3 during the early stages of cellular infection. Furthermore, IFITM induction following IAV or PIV-3 infection does not restrict the late stages of replication of either virus. Our findings show that IFITM proteins can differentially restrict the early stages of infection of two viruses with distinct cellular entry pathways, yet do not influence the late stages of replication for either virus.

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