Gene function in Antarctic krill: determining the role of clock-genes in synchronised behavioural patterns
Lead Research Organisation:
British Antarctic Survey
Abstract
Antarctic krill form an important part of the oceanic ecosystem, acting as predators on plankton and as a food source for a variety of animals including fish, sea birds and aquatic mammals. They migrate in a predictable manner each day, moving to the surface at night to feed and to greater depths during the day to avoid visually guided predators. Krill also synchronise their spawning and moulting cycles to maximise reproductive success. It is not known how these cycles are controlled, but it is likely that they are regulated by 'clock' genes. The circadian clock is an inbuilt mechanism by which the body controls many aspects of behaviour and physiology that oscillate with a 24-hour period, including the sleep-wake cycle, metabolic functions, and activity rhythms. The molecular basis of these cycles was originally described in fruit flies but has since been demonstrated in all animals investigated thus far. Interestingly, the circadian clock maintains the same general design but with remarkable species-specific differences. In addition to the circadian timekeeper, other clock mechanisms exist that control different types of periodicity, such as inter-tidal and lunar cycles, although their molecular architecture is still unknown. The aim of this project is to describe for the first time how daily migrations and monthly spawning-moulting cycles of krill are controlled by clock genes. This will involve a series of behavioural observations, to describe locomotor activity under controlled conditions, and molecular investigations to identify the clock genes associated with the daily and monthly rhythmic phenotypes and their pattern of expression. It has recently been shown that the abundance of krill has dramatically decreased in the Antarctic Ocean over the last 80 years and that this decline is correlated with a reduction in the extent of the sea ice due to global warming. In view of the importance of the species and the apparent threat from changes in climate, it is necessary that we fully understand krill behaviour so that we can monitor how they adapt to climatic changes. In particular, regular recruitment to the stock is necessary to maintain population levels so an understanding of the reproductive cycle is essential. In our work we will use both standard and state of the art methodologies and create new resources that we will make available to the scientific community. It is likely that other pelagic crustaceans have close sequence similarity with homologous krill genes. This will enable others to build on our work, both in the pursuit of scientific aims and also in relation to the farming industry.
Organisations
Publications

Hunt B
(2017)
The Euphausia superba transcriptome database, SuperbaSE: An online, open resource for researchers
in Ecology and Evolution
Description | We have identified the genes that constitute the circadian clock of krill. We have measured their expression and developed a model of their function. We have generated resources. Initially we have developed a collection of sequences aligned on a small glass slide. That is called a microarray and we have used it to understand how genes are expressed under different conditions. More recently, we have sequenced all the genes expressed in the head of this animal across the day and built a searchable database. This is not public yet. When it will been finished and made public it will help other researchers interested in krill in identifying relevant genes. We have described, using our microarray, the changes in gene expression that occur as a result of important physiological phenomena. For instance, we now know which genes are activated or silenced during the monthly cycle of moulting/hardening of the cuticle. Additionally, we have identified the changes in gene expression that correlate with the annual cycle of growth/quiescence. |
Exploitation Route | Our findings and the resources we have generated will help other researchers interested in the ecology and biology of krill. In particular our database will provide a point of entry to sequence information. Furthermore our study of the circadian clock of krill will be of interest to those studying comparative chronobiology |
Sectors | Environment |
Description | krill is a charismatic species, which reports on the health of our planet. We use our findings to inform outreach activities aimed at school children and the general public |
First Year Of Impact | 2007 |
Sector | Environment |
Impact Types | Cultural |
Title | Krill database |
Description | whole head RNAseq was annotated and used to produce a database not yet released |
Type Of Material | Database/Collection of data |
Provided To Others? | No |
Impact | we aim to publish this database within a year |
Description | An Introduction to biological clocks |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Big Bang at Leicester Grammar School, Leicester Grammar School, 25 February 2017, Leicester, UK |
Year(s) Of Engagement Activity | 2017 |
Description | Big Bang at Leicester Grammar School |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | presentation on the circadian clock and its impact on humans and the natural world. People who attended understood the importance of the circadian clock, its impact on health and wellbeing and how to look for sign of the clock in every day life |
Year(s) Of Engagement Activity | 2017 |
Description | Big Bang event at Leicester Grammar School |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | The hands onb activity we presented sparked lots of interests on Genetics and use of fruit fly for medical or fundamental research from parents and pupils We were asked to take part the following year |
Year(s) Of Engagement Activity | 2015 |
Description | Dynamic DNA Day |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | every year 600 pupils and their teachers experience a Genetic Journey that many will always remember. every year more school ask to take part that we can possibly accomodate |
Year(s) Of Engagement Activity | 2006,2007,2008,2009,2011,2013,2014,2015 |
URL | http://www2.le.ac.uk/departments/genetics/genie/outreach/dynamic-dna |
Description | Leicester Grammar Junior School visit |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | We presented a talk on circadian rhythms and the use of Drosophila as a model system to about 61 year 5 & 6 pupils. We showed the flies and how we measure circadian rhythms in activity/rest. We talked about chronotypes and how we can assess them in humans. We had a drawing competition, a 'fly race' competition and a discussion at the end The visit was considered positive by 15 and very positive by 31 pupils. Instead 15 pupils did not enjoy it. The science teacher was very impressed and we werer asked to contribute another project in March/April 2015 |
Year(s) Of Engagement Activity | 2014 |
Description | Loughborough Grammar school visit |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | About 50-60 years 11-13s pupil attended the lecture which was very well received increase interest from pupils |
Year(s) Of Engagement Activity | 2014 |
Description | Measuring circadian rhythms |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | stand with multiple acitivities and examples on how to measure circadian rhythms. Very good turnout of people who asked many questions about the circadian clock, sleep and how improve their sleep/wake cycle |
Year(s) Of Engagement Activity | 2016 |
URL | https://nearme.thebigbangfair.co.uk/Event/?e=2520 |
Description | School visit (Oundle) |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | About 60-70 sixth form students attended a lecture to inform them on the circadian clock There was great interest about the subject and the talk was followed by an interview to be broadcasted on the school radio |
Year(s) Of Engagement Activity | 2006,2014 |
Description | The clock within us |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Public Lecture: The clock within us. Uppingham School, 15 November 2017, Uppingham, UK |
Year(s) Of Engagement Activity | 2017 |
Description | Wurzburg open day |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Open day in Wurzburg, Germany together with our European collaborators. The workshop showed the importance of rhythmicity and photoperiodism in humans and the natural world. The attendees demonstrated increased interest and awareness after attending our activities. |
Year(s) Of Engagement Activity | 2017 |
Description | York Festival of Ideas |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Presented a lecture on the importance of our body clock for health and wellbeing. This was in the context of a symposium on sleep and the body clock. The participants left with increased awareness about the subject. |
Year(s) Of Engagement Activity | 2016 |