LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 3 of total 3

Search options

  1. Article ; Online: RNA immunoprecipitation to identify in vivo targets of RNA editing and modifying enzymes.

    Mukherjee, Priyanka / Raghava Kurup, Reshma / Hundley, Heather A

    Methods in enzymology

    2021  Volume 658, Page(s) 137–160

    Abstract: The past decade has seen an exponential increase in the identification of individual nucleobases that undergo base conversion and/or modification in transcriptomes. While the enzymes that catalyze these types of changes have been identified, the global ... ...

    Abstract The past decade has seen an exponential increase in the identification of individual nucleobases that undergo base conversion and/or modification in transcriptomes. While the enzymes that catalyze these types of changes have been identified, the global interactome of these modifiers is still largely unknown. Furthermore, in some instances, redundancy among a family of enzymes leads to an inability to pinpoint the protein responsible for modifying a given transcript merely from high-throughput sequencing data. This chapter focuses on a method for global identification of transcripts recognized by an RNA modification/editing enzyme via capture of the RNAs that are bound in vivo, a method referred as RNA immunoprecipitation (RIP). We provide a guide of the major issues to consider when designing a RIP experiment, a detailed experimental protocol as well as troubleshooting advice. The RIP protocol presented here can be readily applied to any organism or cell line of interest as well as both RNA modification enzymes and RNA-binding proteins (RBPs) that regulate RNA modification levels. As mentioned at the end of the protocol, the RIP assay can be coupled to high-throughput sequencing to globally identify bound targets. For more quantitative investigations, such as how binding of an RNA modification enzyme/regulator to a given target changes during development/in specific tissues or assessing how the presence or absence of RNA modification affects transcript recognition by a particular RBP (irrespective of a role for the RBP in modulating modification levels); the RIP assay should be coupled to quantitative real-time PCR (qRT-PCR).
    MeSH term(s) High-Throughput Nucleotide Sequencing ; Immunoprecipitation ; RNA/genetics ; RNA/metabolism ; RNA Editing ; RNA-Binding Proteins/genetics ; RNA-Binding Proteins/metabolism
    Chemical Substances RNA-Binding Proteins ; RNA (63231-63-0)
    Language English
    Publishing date 2021-07-14
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1557-7988
    ISSN (online) 1557-7988
    DOI 10.1016/bs.mie.2021.06.005
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: ADAR3 activates NF-κB signaling and promotes glioblastoma cell resistance to temozolomide.

    Raghava Kurup, Reshma / Oakes, Eimile K / Vadlamani, Pranathi / Nwosu, Obi / Danthi, Pranav / Hundley, Heather A

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 13362

    Abstract: The RNA binding protein ADAR3 is expressed exclusively in the brain and reported to have elevated expression in tumors of patients suffering from glioblastoma compared to adjacent brain tissue. Yet, other studies have indicated that glioblastoma tumors ... ...

    Abstract The RNA binding protein ADAR3 is expressed exclusively in the brain and reported to have elevated expression in tumors of patients suffering from glioblastoma compared to adjacent brain tissue. Yet, other studies have indicated that glioblastoma tumors exhibit hemizygous deletions of the genomic region encompassing ADAR3 (10p15.3). As the molecular and cellular consequences of altered ADAR3 expression are largely unknown, here we directly examined the impacts of elevated ADAR3 in a glioblastoma cell line model. Transcriptome-wide sequencing revealed 641 differentially expressed genes between control and ADAR3-expressing U87-MG glioblastoma cells. A vast majority of these genes belong to pathways involved in glioblastoma progression and are regulated by NF-κB signaling. Biochemical and molecular analysis indicated that ADAR3-expressing U87-MG cells exhibit increased NF-κB activation, and treatment with an NF-κB inhibitor abrogated the impacts of ADAR3 on gene expression. Similarly, we found that increased cell survival of ADAR3-expressing cells to temozolomide, the preferred chemotherapeutic for glioblastoma, was due to increased NF-κB activity. Aberrant constitutive NF-κB activation is a common event in glioblastoma and can impact both tumor progression and resistance to treatment. Our results suggest that elevated ADAR3 promotes NF-κB activation and a gene expression program that provides a growth advantage to glioblastoma cells.
    MeSH term(s) Adenosine Deaminase/metabolism ; Brain Neoplasms/pathology ; Cell Line, Tumor ; Glioblastoma/drug therapy ; Glioblastoma/genetics ; Glioblastoma/metabolism ; Humans ; NF-kappa B/metabolism ; RNA-Binding Proteins/metabolism ; Temozolomide/pharmacology ; Temozolomide/therapeutic use
    Chemical Substances NF-kappa B ; RNA-Binding Proteins ; ADARB2 protein, human (EC 3.5.4.4) ; Adenosine Deaminase (EC 3.5.4.4) ; Temozolomide (YF1K15M17Y)
    Language English
    Publishing date 2022-08-03
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-17559-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: RNA binding by ADAR3 inhibits adenosine-to-inosine editing and promotes expression of immune response protein MAVS.

    Raghava Kurup, Reshma / Oakes, Eimile K / Manning, Aidan C / Mukherjee, Priyanka / Vadlamani, Pranathi / Hundley, Heather A

    The Journal of biological chemistry

    2022  Volume 298, Issue 9, Page(s) 102267

    Abstract: Members of the ADAR family of double-stranded RNA-binding proteins regulate one of the most abundant RNA modifications in humans, the deamination of adenosine to inosine. Several transcriptome-wide studies have been carried out to identify RNA targets of ...

    Abstract Members of the ADAR family of double-stranded RNA-binding proteins regulate one of the most abundant RNA modifications in humans, the deamination of adenosine to inosine. Several transcriptome-wide studies have been carried out to identify RNA targets of the active deaminases ADAR1 and ADAR2. However, our understanding of ADAR3, the brain-specific deaminase-deficient ADAR family member, is limited to a few transcripts. In this study, we identified over 3300 transcripts bound by ADAR3 and observed that binding of ADAR3 correlated with reduced editing of over 400 sites in the glioblastoma transcriptome. We further investigated the impact of ADAR3 on gene regulation of the transcript that encodes MAVS, an essential protein in the innate immune response pathway. We observed reduced editing in the MAVS 3' UTR in cells expressing increased ADAR3 or reduced ADAR1 suggesting ADAR3 acts as a negative regulator of ADAR1-mediated editing. While neither ADAR1 knockdown or ADAR3 overexpression affected MAVS mRNA expression, we demonstrate increased ADAR3 expression resulted in upregulation of MAVS protein expression. In addition, we created a novel genetic mutant of ADAR3 that exhibited enhanced RNA binding and MAVS upregulation compared with wildtype ADAR3. Interestingly, this ADAR3 mutant no longer repressed RNA editing, suggesting ADAR3 has a unique regulatory role beyond altering editing levels. Altogether, this study provides the first global view of ADAR3-bound RNAs in glioblastoma cells and identifies both a role for ADAR3 in repressing ADAR1-mediated editing and an RNA-binding dependent function of ADAR3 in regulating MAVS expression.
    MeSH term(s) 3' Untranslated Regions ; Adaptor Proteins, Signal Transducing/genetics ; Adaptor Proteins, Signal Transducing/metabolism ; Adenosine/genetics ; Adenosine Deaminase/genetics ; Adenosine Deaminase/metabolism ; Glioblastoma/genetics ; Humans ; Immunity, Innate ; Inosine/genetics ; Protein Binding ; RNA, Double-Stranded/genetics ; RNA, Double-Stranded/metabolism ; RNA-Binding Proteins/genetics ; RNA-Binding Proteins/metabolism
    Chemical Substances 3' Untranslated Regions ; Adaptor Proteins, Signal Transducing ; MAVS protein, human ; RNA, Double-Stranded ; RNA-Binding Proteins ; Inosine (5A614L51CT) ; ADARB2 protein, human (EC 3.5.4.4) ; Adenosine Deaminase (EC 3.5.4.4) ; Adenosine (K72T3FS567)
    Language English
    Publishing date 2022-07-15
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1016/j.jbc.2022.102267
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top