Development of an automated analytical system for measurement of whole-organism environmental sensitivity of aquatic embryos

Our planet is undergoing unprecedented environmental change and there is an urgent need to understand how species respond to altered abiotic conditions. Development of new technologies has recently seen a revolution in Biology with the advent of tools that enable us to quantify how organisms respond to environmental change at the level of molecules and genes in extremely fine detail. This technological approach to measuring how an organism responds to changes in their environment has become a central theme across Biology. However, technologies for measuring whole-organism level responses have not kept pace, leading to a disconnect between our understanding at these two levels of biological organization. This disconnect is due, in large part, to the challenge of quantifying, in a meaningful way, the complexity and diversity of form and function that is observed at the whole-organism level.

The task of quantifying form and function at the whole-organism level is most challenging for organisms during their early development when both form and function are undergoing dynamic transitions. Yet it is at this time when organisms may be most sensitive to environmental stress. Furthermore, the experience of embryos to such stress can have impacts that persist into later life stages, including reproduction. It is therefore important that the effects of environmental stress on early life stages are incorporated into monitoring and prediction of how organisms will respond to forecasted global environmental change.

A major objective in our laboratory is to gain a better understanding of how environmental stressors affect the physiology of early life stages of aquatic invertebrates. We have developed a unique bio-imaging capability that allows us to produce high-resolution (temporal and spatial) time lapse video of developing embryos, exposed to tightly controlled environmental conditions. We then extract data from these videos to quantify their physiological function using manual video analysis. Such manual data extraction is time consuming and can be an error-prone and subjective process. Consequently, the process of image analysis forms a major bottleneck in the efficacy and application of this approach to quantification of the responses of large numbers of organisms to environmental change.

The main aim of this project is to develop an analytical platform encompassing image analysis pipelines that automate the measurement of a wide range of embryonic features from video. To achieve this we will build image analysis pipelines for measuring functionally relevant traits including growth, gross movement, muscle contraction, heart function, developmental stage and developmental rates. Image analysis pipelines will be embedded within an analytical platform creating a system for organism-wide measurement of different functional traits in individual embryos. Short- and long-term responses of two species (a marine shrimp and freshwater snail) to contrasting temperatures will be used to develop, optimize and validate the analytical framework. The resultant data will enable unrivalled measurement of the responses of developing organisms to factors including environmental stress. This analytical platform would be a powerful tool to any field with an interest in measuring phenotypes in organisms developing in transparent egg capsules e.g. environmental sensitivity measurement, ecotoxicology and drug discovery.

Increasing mean global temperatures are threatening both freshwater and marine ecosystems and the use of contrasting temperature will enable assessment of the efficacy of the automated analytical platform in quantifying the sensitivity of early life stages to a current global threat. The analytical resource being developed in this project will facilitate the development of a fully automated capability for measuring the responses and sensitivities of embryonic stages to environmental stress across different aquatic species.

The main non-academic beneficiaries of the technology developed during this project will be organisations that could benefit from automated high-throughput systems for phenome-wide measurements. Such organisations include, but are not limited to those that have set agendas focused on prediction and mitigation of the effects of climate change on the world's ecosystems and that quantify the responses of aquatic organisms to environmental pollutants. Phenome-wide physiological measurements in non-model organisms would enable more robust predictions of biological sensitivity to environmental change that would be of considerable interest to the Intergovernmental Panel on Climate Change (IPCC), the United Nations Framework Convention on Climate Change (UNFCCC) and the Convention on Biodiversity (CBD). Within Europe the EU Commissions White paper Adapting to Climate Change, encouraged the development of "measures that address biodiversity loss and climate change in an integrated manner". At the European level, the project outcomes will be of interest to the European Environment Agency (EEA) and its agenda to "...help the Community and member countries make informed decisions about improving the environment".

At the National level, the analytical platform developed in this project relates directly to NERC's overall goal of "delivering world-leading environmental research at the frontiers of knowledge enabling society to respond urgently to global climate change and the increasing pressure on natural resources, contributing to UK leadership in predicting the regional and local impacts of environmental change and creating, and supporting vibrant, integrated, research communities". The technology and its results will also be of relevance to the Environment Agency (EA) in their obligations under the Water Framework Directive to improve and maintain water quality, in this case the biological quality and adaptive potential of freshwater species. We will also make results and the technology developed during this project available to DEFRA's Climate Change Risk Assessment 2017.

Research from this project will be disseminated through engagement via educational resources. An educational resource is currently being built by the PI and PDRA, based on videos and data generated using our bio-imaging hardware. This resource provides Virtual Experiments for secondary and undergraduate level educators, offering schools, colleges and universities a cost-effective way of giving pupils important experience in biological observation and experimentation. Video generated during the course of this project will be made available within this educational framework and form a range of educational resources made available to both local schools and undergraduate level Marine Biology students at Plymouth University. Furthermore, during the course of this project the research team will disseminate the aims and technological developments of the project to the public via a public lecture, facilitating dissemination to a wide audience.

The analytical platform developed during the course of this project could have socio-economic impact within the eco-toxicology industry by making viable a broader range of organisms than the traditional model organisms. This could lead to both Reductions in the volume of (protected) animal research, but also Refinements of the end points being employed. These are two of the three principle aims of the 3Rs.