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Upstream activating sequence

About: Upstream activating sequence is a research topic. Over the lifetime, 1633 publications have been published within this topic receiving 100112 citations.


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TL;DR: A detailed mutational analysis revealed that the ribosomal (r)USE is essential for efficient RRNA transcription in vivo and that it functions in an orientation-dependent manner and it was demonstrated that the T.brucei homolog of the recently characterized transcription factor p57 of the related organism Leptomonas seymouri specifically bound to USE and rUSE.
Abstract: In the protist parasite Trypanosoma brucei, the small nuclear spliced leader (SL) RNA and the large rRNAs are key molecules for mRNA maturation and protein synthesis, respectively. The SL RNA gene (SLRNA) promoter recruits RNA polymerase II and consists of a bipartite upstream sequence element (USE) and an element close to the transcription initiation site. Here, we analyzed the distal part of the ribosomal (RRNA) promoter and identified two sequence blocks which, in reverse orientation, closely resemble the SLRNA USE by both sequence and spacing. A detailed mutational analysis revealed that the ribosomal (r)USE is essential for efficient RRNA transcription in vivo and that it functions in an orientation-dependent manner. Moreover, we showed that USE and rUSE are functionally interchangeable and that rUSE stably interacted with an essential factor of SLRNA transcription. Finally, we demonstrated that the T.brucei homolog of the recently characterized transcription factor p57 of the related organism Leptomonas seymouri specifically bound to USE and rUSE. Since p57 and its T.brucei counterpart are homologous to SNAP50, a component of the human small nuclear RNA gene activation protein complex (SNAPc), both SLRNA and RRNA transcription in T.brucei may depend on a SNAPc-like transcription factor.

41 citations

Journal ArticleDOI
TL;DR: UAR function appears dependent on its position relative to the RNA polymerase binding site, suggesting that a particular spatial geometry may be necessary for Fis-dependent and/or factor-independent activation to occur.

41 citations

Journal ArticleDOI
TL;DR: Results indicate that multiple factor-binding regions normally regulate initiation of transcription from the PGK2 promoter, consistent with an "enhanceosome"-like function in this promoter involving multiple bound activator proteins that interact in a combinatorial manner to synergistically promote testis-specific transcription.
Abstract: The PGK2 gene is expressed in a strictly tissue-specific manner in meiotic spermatocytes and postmeiotic spermatids during spermatogenesis in eutherian mammals. Previous results indicate that this is regulated at the transcriptional level by core promoter sequences that bind ubiquitous transcription factors and by sequences in a 40-base pair (bp) upstream enhancer region (E1/E4) that bind tissue-specific transcription factors. Transgenic mice carrying different PGK2 promoter sequences linked to the chloramphenicol acetyltransferase (CAT) reporter gene, one containing only the 40-bp E1/E4 enhancer sequence plus the core promoter and two containing 515 bp of PGK2 promoter but with either the E1/E4 enhancer region or the Sp1-binding site in the core promoter disrupted by in vitro mutagenesis, all showed levels of expression reduced to less than half that of the wild-type 515 PGK2/CAT transgene. These results indicate that multiple factor-binding regions normally regulate initiation of transcription from the PGK2 promoter. The single disruption of any one of these binding activities reduced, but did not abolish, transgene expression. This is consistent with an "enhanceosome"-like function in this promoter involving multiple bound activator proteins that interact in a combinatorial manner to synergistically promote testis-specific transcription.

40 citations

Journal ArticleDOI
TL;DR: The behavior of deletions of the repression sequence suggests that induction of RNR2 may occur, at least in part, through relief of repression.
Abstract: The small subunit of ribonucleotide reductase in Saccharomyces cerevisiae (RNR2) was induced 3- to 20-fold by a variety of DNA-damaging agents. Induction of the RNR2 transcript by at least one of these agents, methyl methanesulfonate, did not require protein synthesis. To identify sequences involved in the regulation of RNR2, we introduced deletions upstream of the transcription start site. Sequences required for induction were contained within a 200-base-pair region that could confer methyl methanesulfonate inducibility on the heterologous CYC1 promoter. This region contained a repression sequence and at least two positive activation sites. One of these activation sites bound RAP1, a protein known to associate with mating-type silencers and the upstream activation sequences of a number of genes. The behavior of deletions of the repression sequence suggests that induction of RNR2 may occur, at least in part, through relief of repression.

40 citations

Journal ArticleDOI
TL;DR: A model based on a shared entry site for RNA polymerase II and competition between major late and IVa2 promoters is proposed to explain the in vitro transcriptional results.
Abstract: The adenovirus IVa2 gene, which is expressed at an intermediate time in the viral infectious cycle, is separated from the adenovirus major late promoter (MLP) 5' start site by 210 base pairs and is transcribed from the opposite strand. In contrast to the MLP, the IVa2 gene does not contain a "TATA" box upstream from its 5' start sites. By using a series of deletion mutants, two upstream control regions that are rich in cytidine residues, one proximal to the cap site at nucleotide positions -39 to -48 and a distal domain between nucleotide positions -152 and -242 have been identified as essential for IVa2 transcription (IVa2 cap site is nucleotide position + 1). Transcription efficiency is decreased by 70-90% after the deletion of a proximal C-rich domain when either linear or supercoiled DNAs were used as template. However, distal sequences functioned as transcriptional control domains only with covalently closed DNA templates. The deletion of both the proximal and distal regions from covalently closed DNA templates reduces the levels of IVa2 transcription by a factor of 100-150. When the plasmid pAd242 that contains the 5' start sites of adenovirus MLP and IVa2 is transcribed, there is essentially a complete suppression of transcription of the adenovirus IVa2 gene. The transcription efficiency of IVa2 is increased 10-fold after deletion of the MLP cap site. A model based on a shared entry site for RNA polymerase II and competition between major late and IVa2 promoters is proposed to explain the in vitro transcriptional results.

40 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20232
20223
20218
20206
20196
20186