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An NCBP3-Domain Protein Mediates Meiotic Silencing by Unpaired DNA.

ABSTRACT: In the filamentous fungus Neurospora crassa, genes unpaired during meiosis are silenced by a process known as meiotic silencing by unpaired DNA (MSUD). MSUD utilizes common RNA interference (RNAi) proteins, such as Dicer and Argonaute, to target homologous mRNAs for silencing. Previously, we demonstrated that nuclear cap-binding proteins NCBP1 and NCBP2 are involved in MSUD. We report here that SAD-8, a protein similar to human NCBP3, also mediates silencing. Although SAD-8 is not essential for either vegetative or sexual development, it is required for MSUD. SAD-8 localizes predominantly in the nucleus and interacts with both NCBP1 and NCBP2. Similar to NCBP1 and NCBP2, SAD-8 interacts with a component (Argonaute) of the perinuclear meiotic silencing complex (MSC), further implicating the involvement of cap-binding proteins in silencing.

SUBMITTER: Boone EC

PROVIDER: S-EPMC7263685 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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An NCBP3-Domain Protein Mediates Meiotic Silencing by Unpaired DNA.

Boone Erin C EC Xiao Hua H Vierling Michael M MM Decker Logan M LM Sy Victor T VT Kennedy Rana F RF Bonham Marilyn A MA Schmitz Shannon F SF John Annie M AM Hammond Thomas M TM Shiu Patrick K T PKT

G3 (Bethesda, Md.) 20200601 6

In the filamentous fungus <i>Neurospora crassa</i>, genes unpaired during meiosis are silenced by a process known as meiotic silencing by unpaired DNA (MSUD). MSUD utilizes common RNA interference (RNAi) proteins, such as Dicer and Argonaute, to target homologous mRNAs for silencing. Previously, we demonstrated that nuclear cap-binding proteins NCBP1 and NCBP2 are involved in MSUD. We report here that SAD-8, a protein similar to human NCBP3, also mediates silencing. Although SAD-8 is not essenti ...[more]

PMID: 32291289

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