Induction of rapid cold hardening by cooling at ecologically relevant rates in Drosophila melanogaster
Induction of rapid cold hardening by cooling at ecologically relevant rates in Drosophila melanogaster
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DOI：
10.1016/s0022-1910(99)00040-2
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发表时间：
1999-08-01
影响因子：
2.2
通讯作者：
Lee, RE
中科院分区：
文献类型：
--
作者：
Kelty, JD;Lee, RE
十多年前，人们假设快速冷硬化过程允许生物体的整体耐寒性跟踪环境温度的变化，就像在昼夜热循环期间自然界中发生的那样。虽然一些研究集中在描述快速冷硬化过程和阐明其所依据的生理机制，但这种现象的生态相关性很少受到关注。我们目前的证据表明，在果蝇快速冷硬化可以诱导在自然发生的速率冷却过程中，以这种方式提供的保护有利于生物体在生态相关的温度。以自然速率（0.05和0.1 ℃ min（-1））冷却的果蝇在暴露于-7和-8 ℃一小时后，比直接转移到这些温度或以0.5或1.0 ℃ min（-1）冷却的果蝇表现出更高的存活率。在整个冷却过程中产生保护（例如，冷却到0 ℃的果蝇比冷却到11 ℃的果蝇更耐寒。而D.在1.0 ℃ min（-1）下冷却的黑腹动物具有临界热最小值（即，发生麻痹的温度）为6.5+/-0.6 ℃，以0.1 ℃ min（-1）的生态相关速率冷却的那些具有显著更低的值3.9+/-0.9 ℃。(C)1999 Elsevier Science Ltd.保留所有权利。
Over a decade ago it was hypothesized that the rapid cold hardening process allows an organism's overall cold tolerance to track changes in environmental temperature, as would occur in nature during diurnal thermal cycles. Although a number of studies have since focused on characterizing the rapid cold hardening process and on elucidating the physiological mechanisms upon which it is based, the ecological relevance of this phenomenon has received little attention. We present evidence that in Drosophila melanogaster rapid cold hardening can be induced during cooling at rates which occur naturally, and that the protection afforded in such a manner benefits the organism at ecologically relevant temperatures. Drosophila melanogaster cooled at natural rates (0.05 and 0.1 degrees C min(-1)) exhibited significantly higher survival after one hour of exposure to -7 and -8 degrees C than did those directly transferred to these temperatures or those cooled at 0.5, or 1.0 degrees C min(-1). Protection accrued throughout the cooling process (e.g., flies cooled to 0 degrees C were more cold tolerant than those cooled to 11 degrees C). Whereas D. melanogaster cooled at 1.0 degrees C min(-1) had a critical thermal minimum (i.e., the temperature at which torpor occurred) of 6.5+/-0.6 degrees C, those cooled at an ecologically relevant rate of 0.1 degrees C min(-1) had a significantly lower value of 3.9+/-0.9 degrees C. (C) 1999 Elsevier Science Ltd. All rights reserved.