The RNA-binding protein QKI-7 recruits the poly(A) polymerase GLD-2 for 3′ adenylation and selective stabilization of microRNA-122

21Citations
Citations of this article
29Readers
Mendeley users who have this article in their library.

Abstract

MicroRNA-122 (miR-122) is highly expressed in hepatocytes, where it plays an important role in regulating cholesterol and fatty acid metabolism, and it is also a host factor required for hepatitis C virus replication. miR-122 is selectively stabilized by 3′ adenylation mediated by the cytoplasmic poly(A) polymerase GLD-2 (also known as PAPD4 or TENT2). However, it is unclear how GLD-2 specifically stabilizes miR-122. Here, we show that QKI7 KH domain-containing RNA binding (QKI-7), one of three isoforms of the QKI proteins, which are members of the signal transduction and activation of RNA (STAR) family of RNA-binding proteins, is involved in miR-122 stabilization. QKI down-regulation specifically decreased the steady-state level of mature miR-122, but did not affect the pre-miR-122 level. We also found that QKI-7 uses its C-terminal region to interact with GLD-2 and its QUA2 domain to associate with the RNA-induced silencing complex protein Argonaute 2 (Ago2), indicating that the GLD-2–QKI-7 interaction recruits GLD-2 to Ago2. QKI-7 exhibited specific affinity to miR-122 and significantly promoted GLD-2–mediated 3′ adenylation of miR-122 in vitro. Taken together, our findings indicate that miR-122 binds Ago2–interacting QKI-7, which recruits GLD-2 for 3′ adenylation and stabilization of miR-122.

Cite

CITATION STYLE

APA

Hojo, H., Yashiro, Y., Noda, Y., Ogami, K., Yamagishi, R., Okada, S., … Suzuki, T. (2020). The RNA-binding protein QKI-7 recruits the poly(A) polymerase GLD-2 for 3′ adenylation and selective stabilization of microRNA-122. Journal of Biological Chemistry, 295(2), 390–402. https://doi.org/10.1074/jbc.RA119.011617

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free