The alternative cap-binding complex is required for antiviral defense in vivo

Abstract

Cellular response to environmental challenges requires immediate and precise regulation of transcriptional programs. During viral infections, this includes the expression of antiviral genes that are essential to combat the pathogen. Transcribed mRNAs are bound and escorted to the cytoplasm by the cap-binding complex (CBC). We recently identified a protein complex consisting of NCBP1 and NCBP3 that, under physiological conditions, has redundant function to the canonical CBC, consisting of NCBP1 and NCBP2. Here, we provide evidence that NCBP3 is essential to mount a precise and appropriate antiviral response. Ncbp3-deficient cells allow higher virus growth and elicit a reduced antiviral response, a defect happening on post-transcriptional level. Ncbp3-deficient mice suffered from severe lung pathology and increased morbidity after influenza A virus challenge. While NCBP3 appeared to be particularly important during viral infections, it may be more broadly involved to ensure proper protein expression.

Multilevel proteomics reveals host perturbations by SARS-CoV-2 and SARS-CoV

“…Lentiviruses production, transduction of cells and antibiotic selection were performed as described previously 23 . RNA-isolation (Macherey-Nagel NucleoSpin RNA plus), reverse transcription (TaKaRa Bio PrimeScript RT with gDNA eraser) and RT-qPCR (Thermo-Fisher Scientific PowerUp SYBR green) were performed as described previously 25 . RNA-isolation for NGS applications was performed according to manufacturer's protocol (Qiagen RNeasy mini kit, RNase free DNase set).…”

“…For AP-MS and AP-WB applications, HA-beads (Sigma-Aldrich and Thermo Fisher Scientific) and Streptactin II beads (IBA Lifesciences) were used. Secondary Abs: HRP and WB imaging was performed as described previously 25 . For the stimulation of cells in the reporter assay, recombinant human interferon-α (IFN-α) was a kind gift from Peter Stäheli, recombinant human IFN-γ were purchased from PeproTech and IVT4 was produced as described before 26 .…”

The mRNA encoding the JUND tumor suppressor detains nuclear RNA-binding proteins to assemble polysomes that are unaffected by mTOR

“…The observation that co-depletion of NCBP2/NCBP3 curtailed NCBP1 association with 5′-caps validated that NCBP1 alternatively forms CBC with NCBP2 or NCBP3 (9). Further evidence demonstrated NCBP3 is essential to mount a precise and appropriate stress response (34). NCBP3-deficient mice suffered from severe lung pathology and increased morbidity after influenza A virus challenge, suggesting NCBP3 supports expression of stress-responsive genes (34).…”

“…Further evidence demonstrated NCBP3 is essential to mount a precise and appropriate stress response (34). NCBP3-deficient mice suffered from severe lung pathology and increased morbidity after influenza A virus challenge, suggesting NCBP3 supports expression of stress-responsive genes (34). Given NCBP2 and NCBP3 function redundantly to support nuclear processing of mRNAs and that NCBP3-deficient cells evoke a reduced antiviral response posited the noncanonical CBC (consisting of NCBP1/NCBP3) is important for translation of stress response genes (31).…”

An NCBP3-Domain Protein Mediates Meiotic Silencing by Unpaired DNA

“…This complex is important for transcription, splicing, pre-mRNA 3¢ end processing, mRNA stability, RNA export, the pioneer round of translation, nonsensemediated mRNA decay, and miRNA biogenesis. In mammals, a third cap-binding protein called NCBP3 has also been characterized (Gebhardt et al 2015(Gebhardt et al , 2019. NCBP3 forms an alternative CBC with NCBP1 and is critical to antiviral defense.…”