Human oncoprotein Musashi-2 N-terminal RNA recognition motif backbone assignment and identification of RNA-binding pocket

Lan Lan; Minli Xing; Justin T Douglas; Philip Gao; Robert P Hanzlik; Liang Xu

doi:10.18632/oncotarget.22540

Human oncoprotein Musashi-2 N-terminal RNA recognition motif backbone assignment and identification of RNA-binding pocket

Oncotarget. 2017 Nov 20;8(63):106587-106597. doi: 10.18632/oncotarget.22540. eCollection 2017 Dec 5.

Authors

Lan Lan¹, Minli Xing², Justin T Douglas², Philip Gao³, Robert P Hanzlik⁴, Liang Xu^{1

5}

Affiliations

¹ Departments of Molecular Biosciences, The University of Kansas, Lawrence, KS, USA.
² Bio-NMR Core Facility, The University of Kansas, Lawrence, KS, USA.
³ Protein Production Group, NIH COBRE in Protein Structure and Function, The University of Kansas, Lawrence, KS, USA.
⁴ Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS, USA.
⁵ Department of Radiation Oncology, The University of Kansas Cancer Center, Kansas City, KS, USA.

Abstract

RNA-binding protein Musashi-2 (MSI2) is a key regulator in stem cells, it is over-expressed in a variety of cancers and its higher expression is associated with poor prognosis. Like Musashi-1, it contains two N-terminal RRMs (RNA-recognition Motifs, also called RBDs (RNA-binding Domains)), RRM1 and RRM2, which mediate the binding to their target mRNAs. Previous studies have obtained the three-dimensional structures of the RBDs of Musashi-1 and the RBD1:RNA complex. Here we show the binding of MSI2-RRM1 to a 15nt Numb RNA in Fluorescence Polarization assay and time resolved Fluorescence Resonance Energy Transfer assay. Using nuclear magnetic resonance (NMR) spectroscopy we assigned the backbone resonances of MSI2-RRM1, and characterized the direct interaction of RRM1 to Numb RNA r(GUAGU). Our NMR titration and structure modeling studies showed that MSI2-RRM1 and MSI1-RBD1 have similar RNA binding events and binding pockets. This work adds significant information to MSI2-RRM1 structure and RNA binding pocket, and contributes to the development of MSI2 specific and MSI1/MSI2 dual inhibitors.

Keywords: Musashi; RNA-binding pocket; RNA-binding protein; backbone assignment; nuclear magnetic resonance.

Abstract

Grants and funding