A cooperative mechanism of target RNA selection via germ-cell-specific RNA-binding proteins NANOS2 and DND1
Takamasa Hirano,
Danelle Wright,
Atsushi Suzuki,
Yumiko Saga
Affiliations
Takamasa Hirano
Mammalian Development Laboratory, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Mishima, Shizuoka 411-8582, Japan
Danelle Wright
Mammalian Development Laboratory, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Mishima, Shizuoka 411-8582, Japan; Department of Genetics, SOKENDAI, 1111 Mishima, Shizuoka 411-8582, Japan
Atsushi Suzuki
Division of Materials Science and Chemical Engineering, Graduate School of Engineering, Yokohama National University, Yokohama, Kanagawa 240-8501 Japan
Yumiko Saga
Mammalian Development Laboratory, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Mishima, Shizuoka 411-8582, Japan; Department of Genetics, SOKENDAI, 1111 Mishima, Shizuoka 411-8582, Japan; Division for Development of Genetic-Engineered Mouse Resource, Genetic Resource Center, National Institute of Genetics, 1111 Mishima, Shizuoka 411-8582, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan; Corresponding author
Summary: The germ-cell-specific RNA-binding protein (RBP) NANOS2 plays a pivotal role in male gonocyte differentiation and spermatogonial stem cell maintenance. Although NANOS2 interacts with the CNOT deadenylation complex and Dead end 1 (DND1) to repress target RNAs, the molecular mechanisms underlying target mRNA selection remain unclear because of the limited cell resource in vivo. Here, we demonstrate that exogenous NANOS2-DND1 suppresses target mRNAs in somatic cells. Using this somatic cell system, we find that NANOS2 interacts with RNA-bound DND1 and recruits the CNOT complex to the mRNAs. However, a fusion construct composed of the CNOT1-binding site of NANOS2 (NIM) and DND1 fails to repress the target gene expression. Therefore, NANOS2 is required not only for recruitment of the CNOT complex but also for selecting the target mRNA with DND1. This study reveals that NANOS2 functions as a second-layer RBP for the target recognition and functional adaptation of DND1.
