Tethering KSRP, a Decay-Promoting AU-Rich Element-Binding Protein, to mRNAs Elicits mRNA Decay

• DOI: 10.1128/mcb.26.10.3695-3706.2006
• Publication Date: 2006-04-28T22:08:50Z
• Authors: Chu-Fang Chou; Alok Mulky; Sushmit Maitra; Wei-Jye Lin; Roberto Gherzi; John Kappes; Ching-Yi Chen
• Keywords: 0301 basic medicine; Binding Sites; RNA Stability; Amino Acid Motifs; RNA-Binding Proteins; Regulatory Sequences, Nucleic Acid; Blotting, Northern; Transfection; Precipitin Tests; Globins; Protein Structure, Tertiary; 3. Good health; 03 medical and health sciences; Genes, Reporter; Trans-Activators; Humans; RNA, Messenger; RNA, Small Interfering; 3' Untranslated Regions; Half-Life; HeLa Cells; Protein Binding

Inherently unstable mRNAs contain AU-rich elements (AREs) in their 3' untranslated regions that act as mRNA stability determinants by interacting with ARE-binding proteins (ARE-BPs). We have destabilized two mRNAs by fusing sequence-specific RNA-binding proteins to KSRP, a decay-promoting ARE-BP, in a tethering assay. These results support a model that KSRP recruits mRNA decay machinery/factors to elicit decay. The ability of tethered KSRP to elicit mRNA decay depends on functions of known mRNA decay enzymes. By targeting the Rev response element of human immunodeficiency virus type 1 by using Rev-KSRP fusion protein, we degraded viral mRNA, resulting in a dramatic reduction of viral replication. These results provide a foundation for the development of novel therapeutic strategies to inhibit specific gene expression in patients with acquired or hereditary diseases.