Micro RNA Isolation from Three Neurosensory Structures in CO2-Exposed Marine Fishes

Faculty #35
Discipline: Ecology, Environmental & Earth Sciences
Subcategory: STEM Research

Andrij Horodysky - Hampton University
Co-Author(s): Isaiah Milton, Carolina Bonin, Nefertiti Smith, Kendra Dorsey, Olivera Stojilovic, Janelle Layton, Kathryn Cruz, Deidre Gibson. All co-authors from Hampton University, Hampton Virginia

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Declines in ocean pH have resulted in physical and behavioral changes in marine organisms, including changes in auditory performance in soniferous marine fishes. Yet physiological responses and underlying molecular mechanisms through which fishes respond to environmental change remain poorly known. MicroRNAs are small (~22 nt) non-coding RNAs known to “fine-tune” gene expression during physiological stress responses. They are highly conserved among taxa, allowing for the exploration of molecular responses in organisms lacking annotated genomes. We therefore assessed microRNA yields of three candidate neurosensory structures: eyes, brain, and endolymph-bathed otoliths obtained from two species, red drum (Sciaenops ocellatus) and Arctic cod (Boreogadus saida). Otoliths were manually pulverized for processing and all tissues were processed in duplicate. Structures were preserved frozen at -20°C in RNAlater (Invitrogen) post dissection. Roughly 0.05g of soft tissue and 0.09g of otolith powder were processed per extraction. Small RNA extractions using a commercial kit (mirVana, Life Technologies) reveraled small RNA yields of: 27.65 ng/μl (eye); 80.25 ng/μl (eye); 20.65 ng/μl (otoliths), while 260/280 ratios ranged from 1.5 to 1.6. Our findings demonstrate successful isolation of microRNAs from all three structures, and suggest the utility of microRNA assays to mechanistically investigate neurosensory deficits in fishes facing environmental change.

Funder Acknowledgement(s): NSF HBCU-UP RIA 1600391; NSF CAREER 1845004

Faculty Advisor: None Listed,
NSF Affiliation: HBCU-UP