Heterogeneous Ribonucleoprotein K (hnRNP K) Binds miR-122, a Mature Liver-Specific MicroRNA Required for Hepatitis C Virus Replication.
Heterogeneous ribonucleoprotein K (hnRNP K) binds to the 5' untranslated region of the hepatitis C virus (HCV) and is required for HCV RNA replication. The hnRNP K binding site on HCV RNA overlaps with the sequence recognized by the liver-specific microRNA, miR-122. A proteome chip containing ∼17,000 unique human proteins probed with miR-122 identified hnRNP K as one of the strong binding proteins. In vitro kinetic study showed hnRNP K binds miR-122 with a nanomolar dissociation constant, in which the short pyrimidine-rich residues in the central and 3' portion of the miR-122 were required for hnRNP K binding. In liver hepatocytes, miR-122 formed a coprecipitable complex with hnRNP K. High throughput Illumina DNA sequencing of the RNAs precipitated with hnRNP K was enriched for mature miR-122. SiRNA knockdown of hnRNP K in human hepatocytes reduced the levels of miR-122. These results show that hnRNP K is a cellular protein that binds and affects the accumulation of miR-122. Its ability to also bind HCV RNA near the miR-122 binding site suggests a role for miR-122 recognition of HCV RNA.
From the ‡Department of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA;
Baochang
B
Fan
§Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli 32001, Taiwan.
F X Reymond
FX
Sutandy
§Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli 32001, Taiwan.
Guan-Da
GD
Syu
From the ‡Department of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA;
Stefani
S
Middleton
From the ‡Department of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA;
Guanghui
G
Yi
§Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli 32001, Taiwan.
Kuan-Yi
KY
Lu
§Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli 32001, Taiwan ckao@indiana.edu cchen103@gmail.com.
Chien-Sheng
CS
Chen
From the ‡Department of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA; ckao@indiana.edu cchen103@gmail.com.
C Cheng
CC
Kao
D001665:Binding Sites; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D063990:Gene Ontology; D016174:Hepacivirus / Q000235:genetics / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D034641:Heterogeneous-Nuclear Ribonucleoprotein K / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D059014:High-Throughput Nucleotide Sequencing; D054884:Host-Pathogen Interactions; D006801:Humans; D008099:Liver / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D058977:Molecular Sequence Annotation; D040081:Protein Array Analysis; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014779:Virus Replication / Q000235:genetics
D034641:Heterogeneous-Nuclear Ribonucleoprotein K; C531907:MIRN122 microRNA, human; D035683:MicroRNAs; D034741:RNA, Small Interfering; D012367:RNA, Viral