title: The long non-coding RNA GAS5 cooperates with the eukaryotic translation initiation factor 4E to regulate c-Myc translation.
abstract: Long noncoding RNAs (lncRNAs) are important regulators of transcription; however, their involvement in protein translation is not well known. Here we explored whether the lncRNA GAS5 is associated with translation initiation machinery and regulates translation. GAS5 was enriched with eukaryotic translation initiation factor-4E (eIF4E) in an RNA-immunoprecipitation assay using lymphoma cell lines. We identified two RNA binding motifs within eIF4E protein and the deletion of each motif inhibited the binding of GAS5 with eIF4E. To confirm the role of GAS5 in translation regulation, GAS5 siRNA and in vitro transcribed GAS5 RNA were used to knock down or overexpress GAS5, respectively. GAS5 siRNA had no effect on global protein translation but did specifically increase c-Myc protein level without an effect on c-Myc mRNA. The mechanism of this increase in c-Myc protein was enhanced association of c-Myc mRNA with the polysome without any effect on protein stability. In contrast, overexpression of in vitro transcribed GAS5 RNA suppressed c-Myc protein without affecting c-Myc mRNA. Interestingly, GAS5 was found to be bound with c-Myc mRNA, suggesting that GAS5 regulates c-Myc translation through lncRNA-mRNA interaction. Our findings have uncovered a role of GAS5 lncRNA in translation regulation through its interactions with eIF4E and c-Myc mRNA.
authors.affiliation: Division of Hematology and Division of Oncology Research, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America.
authors.forename: Guangzhen
authors.initials: G
authors.lastname: Hu
authors.affiliation: Division of Hematology and Division of Oncology Research, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America.
authors.forename: Zhenkun
authors.initials: Z
authors.lastname: Lou
authors.affiliation: Division of Hematology and Division of Oncology Research, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America.
authors.forename: Mamta
authors.initials: M
authors.lastname: Gupta
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D002478:Cells, Cultured; D039561:Eukaryotic Initiation Factor-4E / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D047468:Immunoprecipitation; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011132:Polyribosomes; D011485:Protein Binding; D014176:Protein Biosynthesis; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism*; D062085:RNA, Long Noncoding / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D039561:Eukaryotic Initiation Factor-4E; C561567:GAS5 long non-coding RNA, human; C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D034741:RNA, Small Interfering