酵母中一种“沉默子”的特性：一段具有与转录增强子相反特性的DNA序列。

Characterization of a "silencer" in yeast: a DNA sequence with properties opposite to those of a transcriptional enhancer.

作者信息

Brand A H, Breeden L, Abraham J, Sternglanz R, Nasmyth K

出版信息

Cell. 1985 May;41(1):41-8. doi: 10.1016/0092-8674(85)90059-5.

Abstract

The mating type of yeast is determined by the allele, either a or alpha, at the MAT locus. Two other loci, HML and HMR, contain complete copies of the alpha and a genes, respectively, which are not expressed. The four SIR gene products are required in trans for repression of the silent loci, as are cis-acting sites on either side of HML and HMR, about 1000 bp from the mating-type promoters. We demonstrate that one of these cis-acting sequences, HMRE, is able to switch off at least two nonmating-type promoters. In common with enhancers, it is able to function in either orientation, relatively independently of its position with respect to the regulated promoter, and can act on promoters 2600 bp away. However since HMRE represses, rather than enhances, transcription we have called it a "silencer" sequence.

摘要

酵母的交配型由位于MAT位点的等位基因决定，该等位基因可以是a或α。另外两个位点，HML和HMR，分别包含α和a基因的完整拷贝，但这些基因不表达。四个SIR基因产物在反式作用中是沉默位点抑制所必需的，HML和HMR两侧的顺式作用位点也是如此，这些位点距离交配型启动子约1000 bp。我们证明，这些顺式作用序列之一，即HMRE，能够关闭至少两个非交配型启动子。与增强子一样，它能够以任何方向发挥作用，相对独立于其相对于受调控启动子的位置，并且可以作用于2600 bp以外的启动子。然而，由于HMRE抑制而不是增强转录，我们将其称为“沉默子”序列。