Stress gene (hsp70) sequences and quantitative expression in Milnesium tardigradum (Tardigrada) during active and cryptobiotic stages
Stress gene (hsp70) sequences and quantitative expression in Milnesium tardigradum (Tardigrada) during active and cryptobiotic stages
复制标题
缓生猴（Tardigrada）在活跃期和隐生期的应激基因（hsp70）序列和定量表达
DOI：
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发表时间：
2004
影响因子：
2.8
通讯作者：
H. Köhler
中科院分区：
文献类型：
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作者：
R. O. Schill;G. Steinbrück;H. Köhler
[摘要]延缓米氏杆菌可发生隐生作用，即进入一个可逆的非代谢阶段，可由脱水、冷却以及可能的渗透胁迫和缺氧胁迫诱导。在迟发性疾病中，我们首次描述了三个热休克蛋白(HSP70家族)基因的部分序列，并检测了从活性到隐生菌再回到活动阶段的基因表达。结果显示，HSP70亚型的基因表达模式不同。这三种异构体似乎都是真正的热休克蛋白，因为温度升高可以明显增强转录。异型体1和较低水平的异型体3似乎对隐生作用没有特定的功能。相反，异构体2的转录在活跃期和隐生物期之间的过渡阶段被显著诱导，导致在隐生物期也有相对较高的mRNA拷贝数。这种诱导模式表明，异构体2是与进入隐生阶段的迟缓分枝杆菌个体最相关的HSP70基因。
SUMMARY The eutardigrade Milnesium tardigradum can undergo cryptobiosis, i.e. entry into a reversible ametabolic stage induced by dehydration, cooling and, probably, osmotic and anoxic stress. For the first time in tardigrades, we described partial sequences of three heat-shock protein (hsp70 family) genes and examined gene expression on the way from an active to a cryptobiotic and back to an active stage again. Results showed different patterns of gene expression in the hsp70 isoforms. All three isoforms seem to be true heat-shock proteins since transcription could be clearly enhanced by temperature elevation. Isoform 1 and, at a lower level, isoform 3 do not seem to have a specific function for cryptobiosis. By contrast, transcription of isoform 2 is significantly induced in the transitional stage between the active and the cryptobiotic stage, resulting in a comparatively high mRNA copy number also during cryptobiosis. This pattern of induction implies that isoform 2 is the most relevant hsp70 gene for M. tardigradum individuals entering the cryptobiotic stage.