Strand D J, McDonald J F
Nucleic Acids Res. 1985 Jun 25;13(12):4401-10. doi: 10.1093/nar/13.12.4401.
Adult Drosophila subjected to a variety of environmental stresses that induce classic Drosophila heat shock response simultaneously exhibit a rapid and significant rise in copia homologous transcripts. Levels of Drosophila Adh (alcohol dehydrogenase gene) and 18s ribosomal RNA were unaffected by environmental stress. Copia's ability to be induced by stress is correlated with the presence of sequences homologous to the heat shock promoter consensus sequence which appear to be appropriately positioned within the element's long terminal repeat (LTR). Although the copia-like element 297 also contains homologous sequences within its LTR, they are atypically positioned relative to the element's transcription start site and are non-functional in that the 297 element was not stress inducible. Hence, the position of the consensus sequence relative to a gene's transcription start site may be a factor in stress inducibility.
遭受多种诱导经典果蝇热休克反应的环境应激的成年果蝇,同时会出现copia同源转录本迅速且显著增加的情况。果蝇乙醇脱氢酶(Adh,酒精脱氢酶基因)和18s核糖体RNA的水平不受环境应激影响。copia受应激诱导的能力与热休克启动子共有序列同源序列的存在相关,这些序列似乎恰当地位于该元件的长末端重复序列(LTR)内。尽管类copia元件297在其LTR内也含有同源序列,但它们相对于该元件的转录起始位点位置不典型,并且没有功能,因为297元件不能被应激诱导。因此,共有序列相对于基因转录起始位点的位置可能是应激诱导性的一个因素。