Long noncoding RNA HOTAIR interacts with Y-Box Protein-1 (YBX1) to regulate cell proliferation.

Siting Li,Feng Ge,Qian Xiong,Zongqiang Cui,Bing Wang,Minghai Chen,Qiang Wang,Xue Yang,Mingkun Yang

doi:10.26508/lsa.202101139

Abstract

HOTAIR is a long noncoding RNA (lncRNA) which serves as an important factor regulating diverse processes linked with cancer development. Here, we used comprehensive identification of RNA-binding proteins by mass spectrometry (ChIRP-MS) to explore the HOTAIR-protein interactome. We were able to identify 348 proteins interacting with HOTAIR, allowing us to establish a heavily interconnected HOTAIR-protein interaction network. We further developed a novel near-infrared fluorescent protein (iRFP)-trimolecular fluorescence complementation (TriFC) system to assess the interaction between HOTAIR and its interacting proteins. Then, we determined that HOTAIR specifically binds to YBX1, promotes YBX1 nuclear translocation, and stimulates the PI3K/Akt and ERK/RSK signaling pathways. We further demonstrated that HOTAIR exerts its effects on cell proliferation, at least in part, through the regulation of two YBX1 downstream targets phosphoenolpyruvate carboxykinase 2 (PCK2) and platelet derived growth factor receptor β. Our findings revealed a novel mechanism, whereby an lncRNA is able to regulate cell proliferation via altering intracellular protein localization. Moreover, the imaging tools developed herein have excellent potential for future in vivo imaging of lncRNA-protein interaction.

Highlights

Long noncoding RNAs are RNA molecules that, despite being longer than 200 nts, lack the ability to encode for protein (Fang & Fullwood, 2016)
Many studies have reported the role of long noncoding RNA (lncRNA) HOX Transcript Antisense RNA (HOTAIR) as a regulator of cellular proliferation, apoptosis, and oncogenesis (Wan & Chang, 2010; Zhang et al, 2014)
The wide range of functions regulated by HOTAIR is attributable to its ability to interact with a variety of different proteins, but the exact mechanisms governing these functions remain to be fully characterized

Summary

Introduction

Long noncoding RNAs (lncRNAs) are RNA molecules that, despite being longer than 200 nts, lack the ability to encode for protein (Fang & Fullwood, 2016). The primary means by which lncRNAs mediate biological effects is through interacting with specific proteins (Wan & Chang, 2010; Zhang et al, 2014). HOTAIR regulates the proliferation and metastasis of cancer cells, and for many tumor types, it has been found to be predictive of patient prognosis and progression (Wan & Chang, 2010; Zhang et al, 2014). Via interacting with polycomb repressive complex 2 (PRC2) and regulating the targets downstream of this protein, HOTAIR can mediate cellular metastasis (Gupta et al, 2010; Wan & Chang, 2010; Li et al, 2013), serving as a molecular scaffold which links histone methylase and demethylase activity, resulting in a wide range of unique histone modifications to nearby chromatin (Tsai et al, 2010). Several studies have identified unique roles for HOTAIR that are attributable to its protein interacting partners (Wu et al, 2013; Aiello et al, 2016; Xue et al, 2018). We were able to uncover a novel oncogenic role for HOTAIR consisting in the alteration of the intracellular localization of YBX1

Results

Discussion

Materials and Methods

Ethics statement