Siara Sandwith Ball State University, Antonio Chambers Ball State University, Adam Richardson Ball State University, Peter Beerbower North Dakota State University
Faculty Sponsor(s): Philip Smaldino Ball State UniversityAmyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that results in the breakdown of motor neurons, leading to severe deficiencies in eating, breathing, and moving; 80% of all ALS patients succumb to the disease within 5 years of diagnosis. The most common ALS-linked mutation occurs in the C9ORF72 gene (C9), consisting of a GGGGCC-sequence which becomes repeated hundreds to thousands of times, compared to healthy individuals who have <30 repeats. The mutated C9 sequence folds into extensive G-quadruplex (G4) DNA structures, which form within guanine-rich DNA and RNA sequences. G4s generally provide negative regulation on replication, transcription, and translation, while G4-helicases such as G4 Resolvase 1 (G4R1) (aliases: RHAU, DHX36), potentially provide positive regulation on these processes via unwinding G4s. C9-repeat G4-DNA structures are partially unwound and transcribed, and the resulting RNAs form toxic RNA foci that sequester RNA binding proteins. It is unknown if G4R1 binds to the C9-repeat expansion or if it affects C9-repeat transcription. We hypothesize that G4R1 directly binds to and unwinds C9-G4 DNA and increases the transcription of toxic C9-repeat RNAs. To test this, we will express and isolate recombinant G4R1 (rG4R1) and perform gel mobility shift assays with synthetic C9-G4 DNA. Furthermore, we will use a C9-repeat in vitro transcription assay to determine if rG4R1 affects C9-repeat transcription efficiency. Understanding how G4R1 binds to and affects the transcription of the C9-repeat expansion sequence could provide rationale for future experiments, which explore the possibility of targeting G4R1 as a novel C9 ALS therapeutic strategy.
When & Where
Irwin Library 3rd Floor