期刊
MOLECULAR AND CELLULAR BIOCHEMISTRY
卷 303, 期 1-2, 页码 243-249出版社
SPRINGER
DOI: 10.1007/s11010-007-9468-8
关键词
Littorina littorea; snail; transcription; metabolic suppression; anoxia; mollusc
类别
The intertidal marine snail, Littorina littorea, is an anoxia tolerant species that endures long-term oxygen deprivation using a suite of compensatory metabolic adaptations that includes overall metabolic rate depression. Nuclear run-off assays were used to quantify the relative rates of mRNA transcription in nuclear extracts from hepatopancreas of aerobic and anoxic snails. Total [P-32]-UTP incorporation into RNA by nuclei from 48 h anoxic snails ranged from 42 to 50% of that observed for nuclei from normoxic snails. When this data is transformed with respect to incubation time, the rate of [P-32]-UTP incorporation by nuclei from 48 h anoxic snails showed a decrease of 68% as compared with the normoxic level. Examination of selected expressed sequence tags also showed an overall decrease in mRNA transcription levels in samples derived from anoxic nuclei as compared with normoxic nuclei. Control of ribosomal translation was also examined by assessing the levels of the eukaryotic initiation factors eIF-2 alpha and eIF-4E and the eukaryotic elongation factor-1 gamma (eEF-1 gamma). Levels of eIF-4E and eEF-1 gamma did not change between aerobic and anoxic states, but the amount of phosphorylated inactive eIF-2 alpha rose strongly under anoxic conditions indicating that control of this factor is key to suppressing protein translation in anoxic snails. Since gene transcription is an ATP expensive process in cells, suppression of transcription to minimum levels provides substantial energy savings for the hepatopancreas, and the organism as a whole, under anoxic conditions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据