Baniahmad A, Steiner C, Köhne A C, Renkawitz R
Genzentrum, Max-Planck-Institut für Biochemie, Martinsried, Federal Republic of Germany.
Cell. 1990 May 4;61(3):505-14. doi: 10.1016/0092-8674(90)90532-j.
Silencer elements, by analogy to enhancer elements, function independently of their position and orientation. We show that the chicken lysozyme silencer S-2.4 kb has many other characteristics in common with enhancer elements. The silencer is comprised of modules that independently repress gene activity--repression being increased synergistically when different or identical modules are combined. Repression is effective both on a complete and on a minimal promoter consisting of a TATA box only. One silencer module is bound in vitro by a 75-93 kd protein, termed NeP1; the other can be bound either by the product of the oncogene v-erbA or by the thyroid hormone receptor. This erbA binding site is unusual in that the palindromic sequence is inverted.
沉默子元件与增强子元件类似，其功能不受位置和方向的影响。我们发现鸡溶菌酶沉默子S - 2.4 kb与增强子元件有许多其他共同特征。该沉默子由多个独立抑制基因活性的模块组成，当不同或相同的模块组合时，抑制作用会协同增强。这种抑制作用在完整启动子和仅由TATA框组成的最小启动子上均有效。一个沉默子模块在体外可与一种75 - 93 kd的蛋白质结合，称为NeP1；另一个模块则可与癌基因v - erbA的产物或甲状腺激素受体结合。这个erbA结合位点不同寻常之处在于其回文序列是反向的。
