Behavioural impact of environmental pollutants and parasites in gammarid amphipods

Assoc Prof Herman Wijnen (University of Southampton), Prof Alex T. Ford (University of Portsmouth)
Rationale: 

Echinogammarus marinus is an ecologically important aquatic invertebrate and a good model for untangling the combined and separate impacts of parasitism and environmental pollutants. Collaboratively, [ATF&HW] have shown that E. marinus activity shifts from nocturnal to diurnal when exposed to Artificial Light At Night (ALAN). In addition, ATF has demonstrated that E. marinus is parasitized by a trematode that impacts expression of serotonergic signaling components[2]. Infection may alter E. marinus geotaxis and/or phototaxis, to promote predation by the next host in the trematode life cycle. There is a notable link between altered serotonergic signaling and behavioural change that has been further by ATF’s demonstration that trace amounts of commonly prescribed antidepressant selective serotonin reuptake inhibitors (SSRIs) are sufficient to impact short-term E. marinus phototaxis and geotaxis[3]. This project will answer the question: How do parasites, ALAN, and pharmaceutical pollutants collectively impact the behaviour and associated gene expression of E. marinus? To accomplish this it will be necessary to not only probe how each of these factors act in isolation, but also how they interact. Thus, the separate and combined impact of ALAN and trace amounts of SSRIs on E. marinus behaviour will be studied in both parasitized and uninfected animals.

Methodology: 

Animals will be collected from Langstone Harbour, Portsmouth and visually inspected for the presence of parasites prior to laboratory culture and activity assays in Trikinetics LAM25 monitors in the context of treatments with ALAN and/or SSRI (fluoxetine or sertraline) pollution. Post-analysis PCR tests will be conducted to verify the presence of the trematode Maritrema marinii as well as any other suspected parasites (e.g., microsporidian or paramyxids) to determine whether parasite presence impacts behaviour. Quantitative real-time PCR time course analysis will be conducted to assess the impact of the experimental treatments on genes associated with serotonin biosynthesis and signaling.

Location: 
University of Southampton
Training: 

The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the School of Biological Sciences as well as the University of Portsmouth. Specific training will include:

*Amphipod isolation/culture

*qRT-PCR

*Behavioural analyses

*Bioinformatic analysis

*Quantitative data analysis

*Oral/written presentation skill

Eligibility & Funding Details: 

Please see https://inspire-dtp.ac.uk/how-apply for details.

Background Reading: 

1.    Hughes ME, …, Wijnen H, et al., 2017. Guidelines for Genome-Scale Analysis of Biological Rhythms. J Biol Rhythms, 32(5), pp380-393.

2.    Bossus, et al., Ford AT, 2014. Behavioural and transcriptional changes in the amphipod Echinogammarus marinus exposed to two antidepressants, fluoxetine and sertraline. Aquat Toxicol 151:46-56. doi: 10.1016/j.aquatox.2013.11.025

3.     Guler et al, Fort AT, 2015. Impacts of a newly identified behaviour-altering trematode on its host amphipod: from the level of gene expression to population. Parasitology, 142:1469-1480. doi: 10.1017/S0031182015000918