2002-2003 Science Planning Summary

Biology & Medicine

Dr. Polly Penhale
Program Manager

BO-005-M

NSF/OPP 99-09841
Station: McMurdo Station
RPSC POC: Rob Robbins
Research Site(s): McMurdo Sound

Antifreeze proteins in antarctic fishes: Ecological and organismal physiology, protein structure-function and mechanism, genetics, and evolution
Dr. Arthur L. DeVries
University of Illinois Urbana
Molecular and Integrative Physiology Department
adevries@uiuc.edu
Dr. ChiHing Cheng-DeVries
University of Illinois, Urbana

Deploying Team Members: Christina C Cheng-Devries . Paul Cziko . Arthur L De Vries . Clive W Evans . Kevin C Hoefling . Luke H Hunt . Nelyn E Soto
Research Objectives: Despite temperatures that can dip below 0°C, antarctic waters provide a life sustaining environment for a number of fish species. How are they able to take the most frigid waters on earth through their gills without themselves freezing? A primary reason are the so-called antifreeze proteins, an adaptation found in a number of polar and subpolar species. The Southern Ocean provides the ideal laboratory and molecular biology the ideal probe to study this phenomenon.

This group studies the physiology of fish and larvae from these waters to see how ice grows in biological tissues -- a crystallization process called nucleation -- and how antifreeze glycoproteins (AFGP) inhibit it. The antifreeze function has enabled the antarctic notothenioids to colonize their frigid habitats very successfully. These researchers are mounting comprehensive multidisciplinary analyses of this adaptation at the level of the gene as well as the protein.

This season, deploying team members will:

- Investigate the relationship between the severity of different antarctic marine environments (McMurdo vs. Peninsula) on notothenoid fish antifreeze capacity and function.

- Characterize the antifreeze capacity at both the gene and protein levels of representative species from the five antarcticfamilies of notothenoid fish.

- Characterize the evolution of AFGP gene families and the suborder Notothenoidei using molecular and cytogenetics techniques.


Field Season Overview:
Project team members plan to establish fishing stations on the annual sea ice of McMurdo Sound. The support contractor's crew will drill new holes with the Reed Drill as fish captures dwindle at existing holes. Fish will be captured by diving and setting fish traps. Live specimens will be transported by tracked vehicle to the aquarium at McMurdo Station for further study.

Team members will make day trips by helicopter to the ice edge and to Bratina Island, where there they will deploy fish traps and take conductivity, temperature, and depth (CTD) readings at discrete depths to determine seawater conditions at the collection sites. CTD casts will also be conducted at other sites and at various depths in McMurdo Sound to determine the hydrographic conditions and level of iciness encountered by the McMurdo Sound fish species.

Researchers will travel by helicopter to Cape Bird, where they will deploy a temperature and pressure data logger in about 30 feet of water. The data logger will be left to collect data for one year.

Divers will retrieve developing dragonfish eggs or hatchlings from in situ cages set up during the 2000-2001 field season. They will also collect fertilized eggs of other species at sites in McMurdo Sound. Fertilized eggs will be hatched in the Crary Lab aquarium to study the expression levels of antifreeze glycoproteins during development. Some samples will be returned to the home institution for further analysis.