Title Delayed onset of adult antifreeze activity in juveniles of the Antarctic icefish Chaenocephalus aceratus
Author Bilyk, K.T.; DeVries, A.L.
Author Affil Bilyk, K.T., University of Illinois at Urbana-Champaign, Department of Animal Biology, Urbana, IL
Source Polar Biology, 33(10), p.1387-1397. Publisher: Springer-Verlag, Berlin, Germany. ISSN: 0722-4060
Publication Date Oct. 2010
Notes In English. NSF Grant OPP-Ant-0232006. 35 refs. GeoRef Acc. No: 309097. CRREL Acc. No: 65006005
Index Terms antifreezes; ecology; Antarctica-- Antarctic Peninsula; Southern Ocean; Antarctic Peninsula; Antarctica; biochemistry; Chordata; cold adaptation; organic compounds; physiology; Pisces; proteins; Vertebrata
Abstract Many Antarctic notothenioid species endemic to the Seasonal Pack-ice Zone have converged on adult blood serum freezing points that are several tenths of a degree above the freezing point of seawater. While these fishes share high adult serum freezing points, the development of their freeze avoidance during ontogeny has not been studied. We investigated this in wild caught juveniles of one such species, Chaenocephalus aceratus (family Channichthyidae), using blood serum antifreeze activity as a proxy for their freeze avoidance. Juvenile serum antifreeze activity was significantly below that of adults through the oldest year 2+ specimens collected. This increased at an estimated rate of 0.36810-30.40510-4C day- 1 which, if sustained, would leave C. aceratus below their adult serum antifreeze activity levels of 0.570.08C until 4.2 years after hatching. Underlying the 2.7-fold increase in their serum antifreeze activity from late year 0+ juveniles to adults was an even greater 10.4-fold increase in the concentration of their serum antifreeze glycopeptides, which increased proportionally across all of their serum AFGP size isoforms. With insufficient antifreeze activity to avoid freezing in the ice-laden surface waters, both adult and juvenile C. aceratus are most likely restricted to the year round ice-free waters where a metastable supercooled state can be maintained.
URL http://hdl.handle.net/10.1007/s00300-010-0828-6
Publication Type journal article
Record ID 91210