共查询到20条相似文献,搜索用时 976 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
Compilation and analysis of Bacillus subtilis sigma A-dependent promoter sequences: evidence for extended contact between RNA polymerase and upstream promoter DNA. 总被引:14,自引:1,他引:13 下载免费PDF全文
J D Helmann 《Nucleic acids research》1995,23(13):2351-2360
Sequence analysis of 236 promoters recognized by the Bacillus subtilis sigma A-RNA polymerase reveals an extended promoter structure. The most highly conserved bases include the -35 and -10 hexanucleotide core elements and a TG dinucleotide at position -15, -14. In addition, several weakly conserved A and T residues are present upstream of the -35 region. Analysis of dinucleotide composition reveals A2- and T2-rich sequences in the upstream promoter region (-36 to -70) which are phased with the DNA helix: An tracts are common near -43, -54 and -65; Tn tracts predominate at the intervening positions. When compared with larger regions of the genome, upstream promoter regions have an excess of An and Tn sequences for n > 4. These data indicate that an RNA polymerase binding site affects DNA sequence as far upstream as -70. This sequence conservation is discussed in light of recent evidence that the alpha subunits of the polymerase core bind DNA and that the promoter may wrap around RNA polymerase. 相似文献
9.
10.
11.
12.
13.
14.
15.
16.
J Spychala A G Zimmermann B S Mitchell 《The Journal of biological chemistry》1999,274(32):22705-22712
We have isolated the 5' region of the ecto-5'-nucleotidase (low K(m) 5'-NT) gene and established that a 969-base pair (bp) fragment confers cell-specific expression of a CAT reporter gene that correlates with the expression of endogenous ecto-5'-NT mRNA and enzymatic activity. A 768-bp upstream negative regulatory region has been identified that conferred lymphocyte-specific negative regulation in a heterologous system with a 244-bp deoxycytidine kinase core promoter. DNase I footprinting identified several protected areas including Sp1, Sp1/AP-2, and cAMP response element (CRE) binding sites within the 201-bp core promoter region and Sp1, NRE-2a, TCF-1/LEF-1, and Sp1/NF-AT binding sites in the upstream regulatory region. Whereas the CRE site was essential in mediating the negative activity of the upstream regulatory region in Jurkat but not in HeLa cells, mutation of the Sp1/AP-2 site decreased promoter activity in both cell lines. Electrophoretic mobility shift assay analysis of proteins binding to the CRE site identified both ATF-1 and ATF-2 in Jurkat cells. Finally, phorbol 12-myristate 13-acetate increased the activity of both the core and the 969-bp promoter fragments, and this increase was abrogated by mutations at the CRE site. In summary, we have identified a tissue-specific regulatory region 5' of the ecto-5'-NT core promoter that requires the presence of a functional CRE site within the basal promoter for its suppressive activity. 相似文献
17.
18.
19.
Distant enhancers stimulate the albumin promoter through complex proximal binding sites 总被引:3,自引:0,他引:3
Vorachek WR Steppan CM Lima M Black H Bhattacharya R Wen P Kajiyama Y Locker J 《The Journal of biological chemistry》2000,275(37):29031-29041
20.
The Epstein-Barr virus (EBV) early promoter DR contains a cis-acting element responsive to the EBV transactivator EB1 and an enhancer with constitutive and inducible activities. 总被引:4,自引:15,他引:4 下载免费PDF全文
P Chavrier H Gruffat A Chevallier-Greco M Buisson A Sergeant 《Journal of virology》1989,63(2):607-614