LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 5 of total 5

Search options

  1. Article ; Online: The phosphorylation of carboxyl-terminal eIF2α by SPA kinases contributes to enhanced translation efficiency during photomorphogenesis.

    Chang, Hui-Hsien / Huang, Lin-Chen / Browning, Karen S / Huq, Enamul / Cheng, Mei-Chun

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 3467

    Abstract: Light triggers an enhancement of global translation during photomorphogenesis in Arabidopsis, but little is known about the underlying mechanisms. The phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α) at a conserved serine ... ...

    Abstract Light triggers an enhancement of global translation during photomorphogenesis in Arabidopsis, but little is known about the underlying mechanisms. The phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α) at a conserved serine residue in the N-terminus has been shown as an important mechanism for the regulation of protein synthesis in mammalian and yeast cells. However, whether the phosphorylation of this residue in plant eIF2α plays a role in regulation of translation remains elusive. Here, we show that the quadruple mutant of SUPPRESSOR OF PHYA-105 family members (SPA1-SPA4) display repressed translation efficiency after light illumination. Moreover, SPA1 directly phosphorylates the eIF2α C-terminus under light conditions. The C-term-phosphorylated eIF2α promotes translation efficiency and photomorphogenesis, whereas the C-term-unphosphorylated eIF2α results in a decreased translation efficiency. We also demonstrate that the phosphorylated eIF2α enhances ternary complex assembly by promoting its affinity to eIF2β and eIF2γ. This study reveals a unique mechanism by which light promotes translation via SPA1-mediated phosphorylation of the C-terminus of eIF2α in plants.
    MeSH term(s) Phosphorylation ; Arabidopsis/metabolism ; Arabidopsis/genetics ; Arabidopsis/growth & development ; Eukaryotic Initiation Factor-2/metabolism ; Arabidopsis Proteins/metabolism ; Arabidopsis Proteins/genetics ; Protein Biosynthesis/radiation effects ; Light ; Protein Serine-Threonine Kinases/metabolism ; Protein Serine-Threonine Kinases/genetics ; Gene Expression Regulation, Plant/radiation effects ; Mutation ; Cell Cycle Proteins
    Chemical Substances Eukaryotic Initiation Factor-2 ; Arabidopsis Proteins ; Protein Serine-Threonine Kinases (EC 2.7.11.1) ; SPA1 protein, Arabidopsis ; Cell Cycle Proteins
    Language English
    Publishing date 2024-04-24
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-024-47848-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  2. Article ; Online: HIV-1 capsid stability and reverse transcription are finely balanced to minimize sensing of reverse transcription products

    Eschbach, Jenna E / Puray-Chavez, Maritza / Mohammed, Shawn / Wang, Qiankun / Xia, Ming / Huang, Lin-Chen / Shan, Liang / Kutluay, Sebla B

    mBio

    2024  , Page(s) e0034824

    Abstract: A critical determinant for early post-entry events, the HIV-1 capsid (CA) protein forms the conical core when it rearranges around the dimeric RNA genome and associated viral proteins. Although mutations in CA have been reported to alter innate immune ... ...

    Abstract A critical determinant for early post-entry events, the HIV-1 capsid (CA) protein forms the conical core when it rearranges around the dimeric RNA genome and associated viral proteins. Although mutations in CA have been reported to alter innate immune sensing of HIV-1, a direct link between core stability and sensing of HIV-1 nucleic acids has not been established. Herein, we assessed how manipulating the stability of the CA lattice through chemical and genetic approaches affects innate immune recognition of HIV-1. We found that destabilization of the CA lattice resulted in potent sensing of reverse transcription products when destabilization
    Importance: In HIV-1 particles, the dimeric RNA genome and associated viral proteins and enzymes are encased in a proteinaceous lattice composed of the viral capsid protein. Herein, we assessed how altering the stability of this capsid lattice through orthogonal genetic and chemical approaches impacts the induction of innate immune responses. Specifically, we found that decreasing capsid lattice stability results in more potent sensing of viral reverse transcription products, but not the genomic RNA, in a cGAS-STING-dependent manner. The recently developed capsid inhibitors lenacapavir and GS-CA1 enhanced the innate immune sensing of HIV-1. Unexpectedly, due to increased levels of reverse transcription and cytosolic accumulation of the resulting viral cDNA, capsid mutants with hyperstable cores also resulted in the potent induction of type I interferon-mediated innate immunity. Our findings suggest that HIV-1 capsid lattice stability and reverse transcription are finely balanced to minimize exposure of reverse transcription products in the cytosol of host cells.
    Language English
    Publishing date 2024-03-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2557172-2
    ISSN 2150-7511 ; 2161-2129
    ISSN (online) 2150-7511
    ISSN 2161-2129
    DOI 10.1128/mbio.00348-24
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  3. Article ; Online: COP1-ERF1-SCE1 regulatory module fine-tunes stress response under light-dark cycle in Arabidopsis.

    Lin, Wen-Chi / Chang, Hui-Hsien / Huang, Zi-Bin / Huang, Lin-Chen / Kuo, Wen-Chieh / Cheng, Mei-Chun

    Plant, cell & environment

    2024  Volume 47, Issue 5, Page(s) 1877–1894

    Abstract: ETHYLENE RESPONSE FACTOR 1 (ERF1) plays an important role in integrating hormone crosstalk and stress responses. Previous studies have shown that ERF1 is unstable in the dark and its degradation is mediated by UBIQUITIN-CONJUGATING ENZYME 18. However, ... ...

    Abstract ETHYLENE RESPONSE FACTOR 1 (ERF1) plays an important role in integrating hormone crosstalk and stress responses. Previous studies have shown that ERF1 is unstable in the dark and its degradation is mediated by UBIQUITIN-CONJUGATING ENZYME 18. However, whether there are other enzymes regulating ERF1's stability remains unclear. Here, we use various in vitro and in vivo biochemical, genetic and stress-tolerance tests to demonstrate that both CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) and SUMO-CONJUGATING ENZYME 1 (SCE1) regulate the stability of ERF1. We also performed transcriptomic analyses to understand their common regulatory pathways. We show that COP1 mediates ERF1 ubiquitination in the dark while SCE1 mediates ERF1 sumoylation in the light. ERF1 stability is positively regulated by SCE1 and negatively regulated by COP1. Upon abiotic stress, SCE1 plays a positive role in stress defence by regulating the expression of ERF1's downstream stress-responsive genes, whereas COP1 plays a negative role in stress response. Moreover, ERF1 also promotes photomorphogenesis and the expression of light-responsive genes. Our study reveals the molecular mechanism of how COP1 and SCE1 counteract to regulate ERF1's stability and light-stress signalling crosstalk.
    MeSH term(s) Arabidopsis/metabolism ; Arabidopsis Proteins/genetics ; Arabidopsis Proteins/metabolism ; Ethylenes/metabolism ; Gene Expression Regulation, Plant ; Photoperiod ; Ubiquitin-Protein Ligases/genetics ; Ubiquitin-Protein Ligases/metabolism
    Chemical Substances Arabidopsis Proteins ; Ethylenes ; Ubiquitin-Protein Ligases (EC 2.3.2.27) ; SCE1a protein, Arabidopsis ; ERF11 protein, Arabidopsis ; AT2G32950 protein, Arabidopsis (EC 2.3.2.27)
    Language English
    Publishing date 2024-02-11
    Publishing country United States
    Document type Journal Article
    ZDB-ID 391893-2
    ISSN 1365-3040 ; 0140-7791
    ISSN (online) 1365-3040
    ISSN 0140-7791
    DOI 10.1111/pce.14850
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 80/729: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  4. Article ; Online: Expression of Rta in B Lymphocytes during Epstein–Barr Virus Latency

    Hwang, Sseu-Pei / Huang, Lin-Chen / Wang, Wenhong / Lin, Min-Hsuan / Guo, Zhongwen / Huang, Xianghong / Chang, Li-Kwan

    Journal of Molecular Biology. 2020 Sept., v. 432, no. 19 p.5227-5243

    2020  

    Abstract: Rta of Epstein–Barr virus (EBV) is thought to be expressed only during the lytic cycle to promote the transcription of lytic genes. However, we found that Rta is expressed in EBV-infected B cells during viral latency, at levels detectable by immunoblot ... ...

    Abstract Rta of Epstein–Barr virus (EBV) is thought to be expressed only during the lytic cycle to promote the transcription of lytic genes. However, we found that Rta is expressed in EBV-infected B cells during viral latency, at levels detectable by immunoblot analysis. Latent Rta expression cannot be attributed to spontaneous lytic activation, as we observed that more than 90% of Akata, P3HR1, and 721 cells latently infected by EBV express Rta. We further found that Rta is sequestered in the nucleolus during EBV latency through its interaction with MCRS2, a nucleolar protein. When Rta is sequestered in the nucleolus, it no longer activates RNA polymerase II-driven transcription, thus explaining why Rta expression during latency does not transactivate EBV lytic genes. Additional experiments showed that Rta can bind to 18S rRNA and become incorporated into ribosomes, and a transient transfection experiment showed that Rta promotes translation from an mRNA reporter. These findings reveal that Rta has novel functions beyond transcriptional activation during EBV latency and may have interesting implications for the concept of EBV latency.
    Keywords DNA-directed RNA polymerase ; Human gammaherpesvirus 4 ; cell nucleolus ; molecular biology ; ribosomes ; transcriptional activation ; transfection ; Epstein–Barr virus ; latency ; Rta ; nucleolar sequestration ; EBV ; BL ; LCL ; RRE ; TPA ; RNP-IP ; siRNA
    Language English
    Dates of publication 2020-09
    Size p. 5227-5243.
    Publishing place Elsevier Ltd
    Document type Article ; Online
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2020.07.011
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 63/108: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  5. Article ; Online: Expression of Rta in B Lymphocytes during Epstein-Barr Virus Latency.

    Hwang, Sseu-Pei / Huang, Lin-Chen / Wang, Wen-Hung / Lin, Min-Hsuan / Kuo, Chung-Wen / Huang, Hsiang-Hung / Chang, Li-Kwan

    Journal of molecular biology

    2020  Volume 432, Issue 19, Page(s) 5227–5243

    Abstract: Rta of Epstein-Barr virus (EBV) is thought to be expressed only during the lytic cycle to promote the transcription of lytic genes. However, we found that Rta is expressed in EBV-infected B cells during viral latency, at levels detectable by immunoblot ... ...

    Abstract Rta of Epstein-Barr virus (EBV) is thought to be expressed only during the lytic cycle to promote the transcription of lytic genes. However, we found that Rta is expressed in EBV-infected B cells during viral latency, at levels detectable by immunoblot analysis. Latent Rta expression cannot be attributed to spontaneous lytic activation, as we observed that more than 90% of Akata, P3HR1, and 721 cells latently infected by EBV express Rta. We further found that Rta is sequestered in the nucleolus during EBV latency through its interaction with MCRS2, a nucleolar protein. When Rta is sequestered in the nucleolus, it no longer activates RNA polymerase II-driven transcription, thus explaining why Rta expression during latency does not transactivate EBV lytic genes. Additional experiments showed that Rta can bind to 18S rRNA and become incorporated into ribosomes, and a transient transfection experiment showed that Rta promotes translation from an mRNA reporter. These findings reveal that Rta has novel functions beyond transcriptional activation during EBV latency and may have interesting implications for the concept of EBV latency.
    MeSH term(s) B-Lymphocytes/metabolism ; B-Lymphocytes/pathology ; B-Lymphocytes/virology ; Cell Line ; Epstein-Barr Virus Infections/genetics ; Epstein-Barr Virus Infections/metabolism ; Epstein-Barr Virus Infections/pathology ; Epstein-Barr Virus Infections/virology ; Gene Expression Regulation, Viral ; HEK293 Cells ; Herpesvirus 4, Human/genetics ; Herpesvirus 4, Human/physiology ; Host-Pathogen Interactions ; Humans ; Immediate-Early Proteins/genetics ; Immediate-Early Proteins/metabolism ; RNA-Binding Proteins/metabolism ; Trans-Activators/genetics ; Trans-Activators/metabolism ; Virus Latency
    Chemical Substances BRLF1 protein, Human herpesvirus 4 ; Immediate-Early Proteins ; MCRS1 protein, human ; RNA-Binding Proteins ; Trans-Activators
    Language English
    Publishing date 2020-07-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2020.07.011
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.A 867: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

To top