Upstream repressing sequences

Prelich, G. and Winston, F. (1993) Mutations that suppress the deletion of an upstream activating sequence in yeast involvement of a protein kinase and histone H3 in repressing transcription in vivo. Genetics 135, 665-676. 

MAT locus (in yeast) 471 mediator 471 nuclear receptors 464 promoter 449 promoter-proximal elements 455 repression domain 462 repressors 449 RNA polymerase II 450 silencer sequences 472 TATA box 454 upstream activating sequences (UASs) 457 yeast two-hybrid system 480 zinc finger 463... 

All HREs have the properties of an enhancer in that their activity to induce gene transcription is position and orientation independent. HREs are commonly found within the 2 kb upstream of the promoter of regulated genes but can be much further upstream (93, 94) and even downstream (95) of the start of transcription. Those genes that are repressed by steroid receptors usually do not contain the same HRE sequences (96) because the receptors are often bound to another protein that directly contacts other DNA sequences (97, 98) but see (99). 

Like replication, transcription requires separation of the duplex DNA strands and uses a polymerase to copy the template DNA strand. For transcription, the polymerase is RNA polymerase II, which binds to sequences in the regulatory region of the gene called the promoter. Promoters occur approximately 100 bases upstream (i.e., at the 5 end) from the initiation site of transcription where the first ribonucleotide unit is paired with the template (uracil pairs with adenine). Promoters are usually rich in thymine and adenine in repeating patterns and have been referred to as a TATA box. Initiation of transcription requires many protein cofactors to bind to RNA polymerase to form the active initiation complex. Other regions of DNA known as enhancers may interact with the initiation complex to stimulate or repress transcription. Regulation of transcription is the primary mechanism cells use to control gene expression. ... 

Fur is active when bound to ferrous iron in vivo, and other divalent metals confer activity on the protein in vitro [61, 62]. Thus, Fur is an intracellular iron sensor as well as a regulator. Active Fur binds to the promoter of genes under its control at a cij-acting element with a defined consensus sequence [61]. The identification of DNA sequences similar to this so-called Fur box consensus in the upstream region of a gene is often taken as presumptive evidence for its regulation by Fur. With one possible exception [63], the effect of Fur on transcription is repression, and there is no evidence for an activity for apo-Fur. 

Ferminan, E. and Dominguez, A. (1998) Heterologous protein secretion directed by a repressible acid phosphatase system of Kluyveromyces lactis characterization of upstream region-activating sequences in the KIPH05 gene. Applied and Environmental Microbiology 64, 2403-2408. 

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