LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 4 of total 4

Search options

  1. Article ; Online: Short poly(A) tails are protected from deadenylation by the LARP1-PABP complex.

    Park, Joha / Kim, Myeonghwan / Yi, Hyerim / Baeg, Kyungmin / Choi, Yongkuk / Lee, Young-Suk / Lim, Jaechul / Kim, V Narry

    Nature structural & molecular biology

    2023  Volume 30, Issue 3, Page(s) 330–338

    Abstract: Deadenylation generally constitutes the first and pivotal step in eukaryotic messenger RNA decay. Despite its importance in posttranscriptional regulations, the kinetics of deadenylation and its regulation remain largely unexplored. Here we identify La ... ...

    Abstract Deadenylation generally constitutes the first and pivotal step in eukaryotic messenger RNA decay. Despite its importance in posttranscriptional regulations, the kinetics of deadenylation and its regulation remain largely unexplored. Here we identify La ribonucleoprotein 1, translational regulator (LARP1) as a general decelerator of deadenylation, which acts mainly in the 30-60-nucleotide (nt) poly(A) length window. We measured the steady-state and pulse-chased distribution of poly(A)-tail length, and found that deadenylation slows down in the 30-60-nt range. LARP1 associates preferentially with short tails and its depletion results in accelerated deadenylation specifically in the 30-60-nt range. Consistently, LARP1 knockdown leads to a global reduction of messenger RNA abundance. LARP1 interferes with the CCR4-NOT-mediated deadenylation in vitro by forming a ternary complex with poly(A)-binding protein (PABP) and poly(A). Together, our work reveals a dynamic nature of deadenylation kinetics and a role of LARP1 as a poly(A) length-specific barricade that creates a threshold for deadenylation.
    MeSH term(s) Exoribonucleases/metabolism ; RNA-Binding Proteins/metabolism ; Poly(A)-Binding Proteins/genetics ; Gene Expression Regulation ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Poly A/metabolism
    Chemical Substances Exoribonucleases (EC 3.1.-) ; RNA-Binding Proteins ; Poly(A)-Binding Proteins ; RNA, Messenger ; Poly A (24937-83-5)
    Language English
    Publishing date 2023-02-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2126708-X
    ISSN 1545-9985 ; 1545-9993
    ISSN (online) 1545-9985
    ISSN 1545-9993
    DOI 10.1038/s41594-023-00930-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Cell-free reconstitution reveals the molecular mechanisms for the initiation of secondary siRNA biogenesis in plants.

    Sakurai, Yuriki / Baeg, Kyungmin / Lam, Andy Y W / Shoji, Keisuke / Tomari, Yukihide / Iwakawa, Hiro-Oki

    Proceedings of the National Academy of Sciences of the United States of America

    2021  Volume 118, Issue 31

    Abstract: Secondary small interfering RNA (siRNA) production, triggered by primary small RNA targeting, is critical for proper development and antiviral defense in many organisms. RNA-dependent RNA polymerase (RDR) is a key factor in this pathway. However, how RDR ...

    Abstract Secondary small interfering RNA (siRNA) production, triggered by primary small RNA targeting, is critical for proper development and antiviral defense in many organisms. RNA-dependent RNA polymerase (RDR) is a key factor in this pathway. However, how RDR specifically converts the targets of primary small RNAs into double-stranded RNA (dsRNA) intermediates remains unclear. Here, we develop an in vitro system that allows for dissection of the molecular mechanisms underlying the production of trans-acting siRNAs, a class of plant secondary siRNAs that play roles in organ development and stress responses. We find that a combination of the dsRNA-binding protein, SUPPRESSOR OF GENE SILENCING3; the putative nuclear RNA export factor, SILENCING DEFECTIVE5, primary small RNA, and Argonaute is required for physical recruitment of RDR6 to target RNAs. dsRNA synthesis by RDR6 is greatly enhanced by the removal of the poly(A) tail, which can be achieved by the cleavage at a second small RNA-binding site bearing appropriate mismatches. Importantly, when the complementarity of the base pairing at the second target site is too strong, the small RNA-Argonaute complex remains at the cleavage site, thereby blocking the initiation of dsRNA synthesis by RDR6. Our data highlight the light and dark sides of double small RNA targeting in the secondary siRNA biogenesis.
    MeSH term(s) Cell Line ; Cell-Free System ; Gene Expression Regulation, Plant/physiology ; Plant Proteins/genetics ; Plant Proteins/metabolism ; RNA Interference ; RNA, Small Interfering ; Nicotiana/cytology
    Chemical Substances Plant Proteins ; RNA, Small Interfering
    Language English
    Publishing date 2021-07-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2102889118
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: In vitro

    Baeg, Kyungmin / Tomari, Yukihide / Iwakawa, Hiro-Oki

    Bio-protocol

    2018  Volume 8, Issue 1, Page(s) e2673

    Abstract: RNA-dependent RNA polymerases (RdRPs) in eukaryotes convert single-stranded RNAs into double-stranded RNAs, thereby amplifying small interfering RNAs that play crucial roles in the regulation of development, maintenance of genome integrity and antiviral ... ...

    Abstract RNA-dependent RNA polymerases (RdRPs) in eukaryotes convert single-stranded RNAs into double-stranded RNAs, thereby amplifying small interfering RNAs that play crucial roles in the regulation of development, maintenance of genome integrity and antiviral immunity. Here, we describe a method of
    Language English
    Publishing date 2018-01-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2833269-6
    ISSN 2331-8325 ; 2331-8325
    ISSN (online) 2331-8325
    ISSN 2331-8325
    DOI 10.21769/BioProtoc.2673
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: The poly(A) tail blocks RDR6 from converting self mRNAs into substrates for gene silencing.

    Baeg, Kyungmin / Iwakawa, Hiro-Oki / Tomari, Yukihide

    Nature plants

    2017  Volume 3, Page(s) 17036

    Abstract: It remains unclear how post-transcriptional gene silencing (PTGS) in plants discriminates aberrant RNAs from canonical messenger RNAs (mRNAs). The key step of plant PTGS is the conversion of aberrant RNAs into double-stranded RNAs by RNA-DEPENDENT RNA ... ...

    Abstract It remains unclear how post-transcriptional gene silencing (PTGS) in plants discriminates aberrant RNAs from canonical messenger RNAs (mRNAs). The key step of plant PTGS is the conversion of aberrant RNAs into double-stranded RNAs by RNA-DEPENDENT RNA POLYMERASE6 (RDR6). Here, we show that RDR6 itself selects aberrant poly(A)-less mRNAs over canonical polyadenylated mRNAs as templates at the initiation step of complementary strand synthesis. This mechanism can be viewed as an innate safeguard against 'self-attack' by PTGS.
    MeSH term(s) Arabidopsis/genetics ; Arabidopsis Proteins/genetics ; Gene Expression Regulation, Plant/genetics ; Gene Silencing/physiology ; RNA Replicase/genetics ; RNA, Messenger/genetics ; RNA, Plant/genetics
    Chemical Substances Arabidopsis Proteins ; RNA, Messenger ; RNA, Plant ; RDR6 protein, Arabidopsis (EC 2.7.7.48) ; RNA Replicase (EC 2.7.7.48)
    Language English
    Publishing date 2017-03-20
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2055-0278
    ISSN (online) 2055-0278
    DOI 10.1038/nplants.2017.36
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top