Sachs L, de Luze A, Lebrun J J, Kelly P A, Demeneix B A
Laboratoire de Physiologie Générale et Comparée, URA CNRS 90, M.N.H.N, Paris, France.
Endocrinology. 1996 May;137(5):2191-4. doi: 10.1210/endo.137.5.8612569.
In vivo gene transfer and RNase protection assay were used to follow thyroid hormone (T3)-dependent regulation of myosin heavy chain (myHC) genes in Xenopus tadpole dorsal muscle. One embryonic and one adult myHC form were measured by each approach. RNase protection assay showed that T3 decreased expression of endogenous embryonic mRNA (E3), but increased adult (A7) transcripts. Gene transfer showed that T3 exerted transcriptional effects on mammalian embryonic and adult myHc promoters injected into the same muscle. The kinetics and profiles of the transcriptional responses were superimposable on endogenous responses. The results strengthen the use of in vivo approaches for determining the roles of transcription factors and cis-regulatory sequences in integrated contexts.
利用体内基因转移和核糖核酸酶保护试验来追踪非洲爪蟾蝌蚪背部肌肉中甲状腺激素（T3）依赖性的肌球蛋白重链（myHC）基因调控。每种方法都检测了一种胚胎型和一种成年型的myHC形式。核糖核酸酶保护试验表明，T3降低了内源性胚胎mRNA（E3）的表达，但增加了成年型（A7）转录本。基因转移表明，T3对注射到同一块肌肉中的哺乳动物胚胎型和成年型myHc启动子发挥转录作用。转录反应的动力学和模式与内源性反应重叠。这些结果强化了在整合背景下使用体内方法来确定转录因子和顺式调控序列的作用。
