Date of Award

8-2020

Document Type

Thesis

Degree Name

Master of Science (MS)

College/School

College of Science and Mathematics

Department/Program

Biology

Thesis Sponsor/Dissertation Chair/Project Chair

John Gaynor

Committee Member

Paul A. X. Bologna

Committee Member

Robert Meredith

Abstract

Gonionemus vertens appearances and stings have been increasing internationally. The medusae of this hydrozoan are small, having an average bell diameter of 2 cm, and are noted for their potent stings that can lead to systemic pain, hospitalization, and disrupted neurocognitive function. They are typically found among algae and in eelgrass beds during the summer months when the population peaks, thus posing a seasonal public health concern for those participating in recreational water activities. To explore the nature of this species’ toxic sting, transcriptome libraries were constructed from poly A+ mRNA isolated from mature individuals and sequenced on an Illumina Mi-Seq platform. Raw RNA-seq data was assembled de novo using Trinity and assembly completeness was verified via BUSCO analysis. The Venomix pipeline was used to extract venom candidates from the resulting transcriptome. A preliminary characterization of the transcripts was completed using GO FEAT and supplemental protein structural analysis by Phyre2. An initial analysis based on categorization of BLAST hits shows that metalloproteases and kunitz-type protease inhibitors dominate the venom composition. Expression analysis corroborates the dominance of metalloproteases, particularly those that are astacin-like and contain the ShK domain, which is known to be a potent potassium channel inhibitor with neurotoxic effects. Many other candidates including neprilysin, plancitoxin, hyaluronidase, and jellyfish pore-forming toxin align with many of the observed physiological symptoms of G. vertens envenomation. An astacin-like metalloprotease with a unique combination of ShK and discoidin domains was also identified. This study is the first to assemble the transcriptome of G. vertens from which venom candidates were extracted and serves as a resource to discover potentially novel proteins with broad applications and to better understand the diversity of cnidarian venoms.

File Format

PDF

Included in

Biology Commons

Share

COinS