title: RNA helicase A activity is inhibited by oncogenic transcription factor EWS-FLI1.
abstract: RNA helicases impact RNA structure and metabolism from transcription through translation, in part through protein interactions with transcription factors. However, there is limited knowledge on the role of transcription factor influence upon helicase activity. RNA helicase A (RHA) is a DExH-box RNA helicase that plays multiple roles in cellular biology, some functions requiring its activity as a helicase while others as a protein scaffold. The oncogenic transcription factor EWS-FLI1 requires RHA to enable Ewing sarcoma (ES) oncogenesis and growth; a small molecule, YK-4-279 disrupts this complex in cells. Our current study investigates the effect of EWS-FLI1 upon RHA helicase activity. We found that EWS-FLI1 reduces RHA helicase activity in a dose-dependent manner without affecting intrinsic ATPase activity; however, the RHA kinetics indicated a complex model. Using separated enantiomers, only (S)-YK-4-279 reverses the EWS-FLI1 inhibition of RHA helicase activity. We report a novel RNA binding property of EWS-FLI1 leading us to discover that YK-4-279 inhibition of RHA binding to EWS-FLI1 altered the RNA binding profile of both proteins. We conclude that EWS-FLI1 modulates RHA helicase activity causing changes in overall transcriptome processing. These findings could lead to both enhanced understanding of oncogenesis and provide targets for therapy.
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA hve2@georgetown.edu.
authors.forename: Hayriye Verda
authors.initials: HV
authors.lastname: Erkizan
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Schneider
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Kamal
authors.initials: K
authors.lastname: Sajwan
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Garrett T
authors.initials: GT
authors.lastname: Graham
authors.affiliation: Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA.
authors.forename: Brittany
authors.initials: B
authors.lastname: Griffin
authors.affiliation: Department of Radiation Medicine, Georgetown University Medical Center, 3970 Reservoir Road NW, New Research Building E220, Washington, DC 20007, USA.
authors.forename: Sergey
authors.initials: S
authors.lastname: Chasovskikh
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Youbi
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Abraham
authors.initials: A
authors.lastname: Kallarakal
authors.affiliation: Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA.
authors.forename: Maksymilian
authors.initials: M
authors.lastname: Chruszcz
authors.affiliation: Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA.
authors.forename: Radhakrishnan
authors.initials: R
authors.lastname: Padmanabhan
authors.affiliation: Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA.
authors.forename: John L
authors.initials: JL
authors.lastname: Casey
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Aykut
authors.initials: A
authors.lastname: Üren
authors.affiliation: Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Toretsky
mesh_terms: D053487:DEAD-box RNA Helicases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007211:Indoles / Q000494:pharmacology; D008958:Models, Molecular; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015514:Oncogene Proteins, Fusion / Q000378:metabolism*; D051789:Proto-Oncogene Protein c-fli-1 / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D034802:RNA-Binding Protein EWS / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: C106031:EWS-FLI fusion protein; D007211:Indoles; D009363:Neoplasm Proteins; D015514:Oncogene Proteins, Fusion; D051789:Proto-Oncogene Protein c-fli-1; D034802:RNA-Binding Protein EWS; D011994:Recombinant Proteins; C562345:YK 4-279; D012313:RNA; C098487:DHX9 protein, human; D053487:DEAD-box RNA Helicases