NVL2, a nucleolar AAA-ATPase, is associated with the nuclear exosome and is involved in pre-rRNA processing

• Published in: Biochemical and biophysical research communications 2015-08, Vol.464 (3), p.780-786
• Main Authors: Yoshikatsu, Yuki, Ishida, Yo-ichi, Sudo, Haruka, Yuasa, Keizo, Tsuji, Akihiko, Nagahama, Masami
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; AAA-ATPase; Adenosine Triphosphatases - chemistry; Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Amino Acid Substitution; ATP-ASE; ATPases Associated with Diverse Cellular Activities; BIOSYNTHESIS; Cell Nucleus - metabolism; DEFECTS; Exoribonucleases - metabolism; Exosome Multienzyme Ribonuclease Complex - metabolism; Gene Knockdown Techniques; HEK293 Cells; Humans; INTERACTIONS; Membrane Proteins - antagonists & inhibitors; Membrane Proteins - genetics; Membrane Proteins - metabolism; Models, Biological; Mutagenesis, Site-Directed; Mutation; MUTATIONS; Nuclear Proteins - metabolism; NVL2; Pre-rRNA processing; Protein Structure, Tertiary; Ribosome biogenesis; Ribosome Subunits, Large, Eukaryotic - metabolism; RNA; RNA exosome; RNA Helicases - metabolism; RNA Interference; RNA Precursors - metabolism; RNA Processing, Post-Transcriptional
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2015.07.032

Nuclear VCP-like 2 (NVL2) is a member of the chaperone-like AAA-ATPase family and is involved in the biosynthesis of 60S ribosomal subunits in mammalian cells. We previously showed the interaction of NVL2 with a DExD/H-box RNA helicase MTR4/DOB1, which is a known cofactor for an exoribonuclease complex, the exosome. This finding implicated NVL2 in RNA metabolic processes during ribosome biogenesis. In the present study, we found that a series of mutations within the ATPase domain of NVL2 causes a defect in pre-rRNA processing into mature 28S and 5.8S rRNAs. Co-immunoprecipitation analysis showed that NVL2 was associated with the nuclear exosome complex, which includes RRP6 as a nucleus-specific catalytic subunit. This interaction was prevented by depleting either MTR4 or RRP6, indicating their essential role in mediating this interaction with NVL2. Additionally, knockdown of MPP6, another cofactor for the nuclear exosome, also prevented the interaction by causing MTR4 to dissociate from the nuclear exosome. These results suggest that NVL2 is involved in pre-rRNA processing by associating with the nuclear exosome complex and that MPP6 is required for maintaining the integrity of this rRNA processing complex. •ATPase-deficient mutants of NVL2 have decreased pre-rRNA processing.•NVL2 associates with the nuclear exosome through interactions with MTR4 and RRP6.•MPP6 stabilizes MTR4-RRP6 interaction and allows NVL2 to interact with the complex.