Channels and pumps—determinants of metabolic cold adaptation strategies

1988 ◽  
Vol 90 (3) ◽  
pp. 515-519 ◽  
Author(s):  
P.W. Hochachka
Keyword(s):  
Cold Adaptation ◽  
Adaptation Strategies ◽  
Metabolic Cold Adaptation

Metabolic opportunists: feeding and temperature influence the rate and pattern of respiration in the high arctic woollybear caterpillar gynaephora groenlandica (Lymantriidae)

1999 ◽  
Vol 202 (1) ◽  
pp. 47-53 ◽  
Author(s):  
V.A. Bennett ◽  
O. Kukal ◽  
R.E. Lee
Keyword(s):  
Cold Adaptation ◽  
Freeze Tolerance ◽  
High Arctic ◽  
Temperature Influence ◽  
Temperature Changes ◽  
Respiration Rates ◽  
Polar Environment ◽  
Lepidopteran Larvae ◽  
Gynaephora Groenlandica ◽  
Metabolic Cold Adaptation

Arctic woollybear caterpillars, Gynaephora groenlandica, had the capacity to rapidly and dramatically increase respiration rates up to fourfold within 12–24 h of feeding and exhibited similar decreases in respiration of 60–85 % in as little as 12 h of starvation. At the peak of their feeding season, the respiration rates of caterpillars also increased significantly with temperature from 0.5 to 22 degreesC for both fed and starved caterpillars (Q10=1-5). Indicative of diapause, late season caterpillars had depressed respiration rates which were less sensitive to temperature changes (Q10 approximately 1.5), while respiration rates for caterpillars that had spun hibernacula were even lower. G. groenlandica did not appear to demonstrate metabolic cold adaptation compared with other temperate lepidopteran larvae. The seasonal capacity to adjust metabolic rate rapidly in response to food consumption and temperature (which can be elevated by basking) may promote the efficient acquisition of energy during the brief (1 month) summer growing and feeding season, while conserving energy by entering diapause when conditions are less favorable. These adaptations, along with their long 15–20 year life cycle and the retention of freeze tolerance year-round, promote the survival of G. groenlandica in this harsh polar environment.

scholarly journals Metabolic cold adaptation in fishes occurs at the level of whole animal, mitochondria and enzyme

2011 ◽  
Vol 279 (1734) ◽  
pp. 1740-1747 ◽  
Author(s):  
Craig R. White ◽  
Lesley A. Alton ◽  
Peter B. Frappell
Keyword(s):  
High Latitude ◽  
Cold Adaptation ◽  
Citrate Synthase ◽  
High Standard ◽  
Metabolic Rates ◽  
Thermal Plasticity ◽  
Metabolic Compensation ◽  
Low Latitudes ◽  
Effects Of Temperature ◽  
Metabolic Cold Adaptation

Metabolic cold adaptation (MCA), the hypothesis that species from cold climates have relatively higher metabolic rates than those from warm climates, was first proposed nearly 100 years ago and remains one of the most controversial hypotheses in physiological ecology. In the present study, we test the MCA hypothesis in fishes at the level of whole animal, mitochondria and enzyme. In support of the MCA hypothesis, we find that when normalized to a common temperature, species with ranges that extend to high latitude (cooler climates) have high aerobic enzyme (citrate synthase) activity, high rates of mitochondrial respiration and high standard metabolic rates. Metabolic compensation for the global temperature gradient is not complete however, so when measured at their habitat temperature species from high latitude have lower absolute rates of metabolism than species from low latitudes. Evolutionary adaptation and thermal plasticity are therefore insufficient to completely overcome the acute thermodynamic effects of temperature, at least in fishes.

A comparison of the metabolic cost of protein synthesis in stenothermal and eurythermal isopod crustaceans

1996 ◽  
Vol 271 (5) ◽  
pp. R1295-R1303 ◽  
Author(s):  
N. M. Whiteley ◽  
E. W. Taylor ◽  
A. J. el Haj
Keyword(s):  
Protein Synthesis ◽  
Oxygen Uptake ◽  
G Protein ◽  
Cold Adaptation ◽  
Metabolic Cost ◽  
Energetic Cost ◽  
Protein Synthesis Inhibitor ◽  
Synthesis Inhibitor ◽  
The Antarctic ◽  
Metabolic Cold Adaptation

To examine the presence of metabolic cold adaptation in Antarctic isopods, whole animal rates of oxygen uptake (MVo2) and protein synthesis were measured in Glyptonotus antarcticus at 0 degree C and compared with the temperature isopod Idotea rescata at 4 and 14 degrees C. The specific relationship between rates of metabolism and protein synthesis was investigated by injecting animals with cycloheximide, a protein synthesis inhibitor. In G. antarcticus, routine MVo2 was 11.10 +/- 0.89 mumol.kg-1.min-1 (n = 19 animals), and ks was 0.24 +/- 0.04% protein synthesized/day (n = 8 animals). Comparison with I. rescata showed that standardized whole animal MVo2 decreased with temperature (temperature quotient = 1.99), but whole animal ks was considerably lower in the Antarctic isopod; 66 and 22% of total MVo2 was attributable to protein synthesis in G. antarcticus at 0 degree C and I. rescata at 4 degrees C, respectively. The energetic cost of protein synthesis was four times higher in G. antarcticus at 885 +/- 141 mmol ATP/g protein (n = 5 animals) compared with 237 +/- 76 mmol ATP/g protein (n = 6) in I. rescata. G. antarcticus does not show metabolic rate compensation and maintains extremely low ks levels because of the relatively high energetic cost of protein synthesis.

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