Venom on ice: Novel venoms from Antarctic marine animals 2007/08

Brief description

Metadata record for data from ASAC Project 2897
See the link below for public details on this project.

Public
The aim of this multi-disciplinary proposal is to examine the molecular evolution of toxic proteins across the full taxonomical spectrum of venomous Antarctic marine animals. The project will create a comparative encyclopedia of the evolution of the venom system in the Antarctic marine animal kingdom and elucidate the underlying structure-function relationships between these toxic proteins. Through a process utilising cutting edge analytical techniques, such as cDNA cloning and molecular modelling, a feedback loop of bioactivity testing will be created to contribute substantially towards the area of drug design and development from toxic animal peptides.

Project objectives:
The aim of this project is to investigate the evolution of the molecular, structural and functional properties of Antarctic marine animal venom systems. This integrative project aims to investigate the origin and evolution of secreted proteins in the venom glands of toxic polar animals by means of:
- Analysis of mechanisms of evolution in multigene families.
- Phylogenetic analysis of evolutionary relationships among secreted proteins in the venom glands of major lineages;
- Search for correlations between: (i) evolution of venom gland structure (ii) molecular evolution of venom components, and (iii) ecological specialisation of the animal
- Bioactivity studies will be conducted upon representative purified or synthesised proteins.
- A first ever comparison of the convergent strategies between Arctic and Antarctic endemic fauna.

The results will help us to understand protein evolution, will cast light on the classic problem of how venom systems evolve, and may provide leads in the search for commercially-exploitable venom proteins.

Taken from the 2008-2009 Progress Report:
Progress against objectives:
We have completed the genetic analyses of the specimens and sequence analyses. Phylogenetic positioning is robust other than a few deep level nodes. We are undertaking a second round of genetic analyses using different primers in order to resolve these nodes. Biochemical analyses of crude protein secretions from the posterior salivary (venom) glands has revealed temperature specific modifications of some of the venom components to adapt them to the polar conditions. We have tested the secretions in a battery of assays. We are now repeating those assays using purified proteins in order to determine which types are responsible for particular effects and also investigate synergistic interactions.

Taken from the 2009-2010 Progress Report:
Progress against objectives:
We have undertaken genetic analyses of the specimens collected, and investigated specific adaptations of their venom systems. Results to-date include:
- Antarctic octopuses are more genetically diverse than previously appreciated, including at least one new genus
- an inverse relationship exists between the size of the venom gland and the size of the beak
- their venoms have undergone temperature-specific adaptations Quality: The values provided in temporal and spatial coverage are approximate only.

Taken from the 2008-2009 Progress Report:
Field work:
We conducted fieldwork to obtain octopus specimens from the northern limit in Norwegian sub-polar waters.

Laboratory activity/analysis:
We have used the COI genetic marker to examine the phylogenetic relationships of the specimens collected. This marker was adequate for some nodes but not others. Thus other genetic markers are being evaluated for relative usefulness. We have also conducted different assays to examine the enzymatic properties of the venoms. In the next year we will use reverse phase HPLC to purify the crude venoms into individual toxins and examine their properties. We will also commence cDNA library construction in order to obtain full-length sequences of the toxins. This will allow for comparison with those we have obtained from temperate and tropical species with the aim of identifying regions that confer temperature specific activity.

Taken from the 2009-2010 Progress Report:
Laboratory activity/analysis
- genetic fingerprinting of each specimen collecting
- analysis of temperature-specific adaptations of different enzyme types present in the venoms

Notes

Includes: point occurrence data