NSFGEO-NERC: The Blueprint for Marine Biomineralization in a Changing Climate

This is a project jointly funded by the National Science Foundation Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget.

Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own investigators and component of the work. This project will study shell formation in an important marine organism, the foraminifera. Foraminifera are sand-grain-sized, shell-forming plankton.

They are common in the modern ocean and in the fossil record. Their shell composition depends on ocean conditions during growth, and so their fossils are used to record Earth’s climate history. Foraminifera shells also play an important role in the carbon cycle.

They are responsible for up to 80% of the carbon that is deposited on the seafloor. Understanding shell formation is important because changes in ocean warming and pH threatens foraminiferal survival. However, foraminiferal shell formation is not well understood.

In part this is because the genome for these species is unknown. A genome is required to identify proteins responsible for shell forming processes. This study will close this knowledge gap by identifying key shell proteins in two species.

The project will grow specimens under conditions that mimic likely future climate and will identify differences in shell proteins in response to growth conditions. The results will provide a 'blueprint for shell formation' in foraminifera. The genome and protein sequence datasets will be useful to researchers in marine biology and chemistry, evolution, climate science, and material science.

Broader impacts include graduate and undergraduate student field research experience and training. International participants will also gain experience growing foraminifera in the laboratory.

This multidisciplinary project will establish the molecular biological controls of biomineralization in two model species of single-celled foraminifera. This is crucial for quantifying the marine calcite budget and assessing the impact of calcification feedbacks on future atmospheric carbon dioxide, as well as producing accurate interpretation of the foraminiferal shell geochemical archive that underpins future climate change projections.

Despite decades of research into how foraminifera biomineralization, our understanding lags far behind other marine calcifiers, owing to a lack of genome/transcriptome information that is vital for identification of foraminifera shell matrix proteins (SMPs). SMPs in the shell’s organic matrix layers trigger nucleation of calcium carbonate and are responsible for shell formation and its geochemical properties.

The identification of SMPs will aid in our understanding of how biomineralization will respond to future environmental change and thus it is imperative that we resolve biomineralization mechanisms in these critically important marine calcifiers. This project addresses that need. The interdisciplinary team’s expertise will be capitalized to produce the genome and transcriptome data required via Single Cell Sequencing and exploit innovative high throughput microfluidic approaches to identify and characterize key SMPs in foraminifera biomineralization.

Foraminifera culturing experiments will be conducted to investigate molecular/protein responses to different climate scenarios. The project team combines a unique set of skills that enable us, for the first time, to investigate all aspects of the biological control of the biomineralization process within the foraminifera. By linking genes, transcripts, proteins, and calcite formation our aim is to generate a ‘blueprint of biomineralization’.

Identifying these key molecules will provide the first ever opportunity to identify any changes in the foraminifera SMPs in response to changes in temperature and pH, and assess the vulnerability of foraminiferal biomineralization to future climate scenarios.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.