Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P51532 (
transcriptional activator
)
6,546
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The E. coli nrd operon contains the genes encoding the two subunits of
ribonucleoside diphosphate reductase
. We found that the IciA protein binds specifically to the AT-rich upstream region of nrd promoter. In vivo overexpression of IciA increases the expression of nrd gene by four- to five-fold, suggesting that IciA functions as a
transcriptional activator
for the nrd gene.
...
PMID:Effect of IciA protein on the expression of the nrd gene encoding ribonucleoside diphosphate reductase in E. coli. 981 53
Two genes encoding thioredoxin are found on the Escherichia coli genome. Both of them are capable of reducing protein disulfide bonds in vivo and in vitro. The catalytic site contains a Cys-X(1)-X(2)-Cys motif in a so-called thioredoxin fold. Thioredoxin 2 has two additional pairs of cysteines in a non-conserved N-terminal domain. This domain does not appear to be important for the function of thioredoxin 2 in donating electrons to
ribonucleotide reductase
, 3'-phosphoadenylsulfate-reductase, or the periplasmic disulfide isomerase DsbC. Our results suggests that the two thioredoxins are equivalent for most of the in vivo functions that were tested. On the other hand, transcriptional regulation is different. The expression of trxC is regulated by the
transcriptional activator
OxyR in response to oxidative stress. Oxidized OxyR binds directly to the trxC promoter and induces its expression in response to elevated hydrogen peroxide levels or the disruption of one or several of the cytoplasmic redox pathways. Mutants lacking thioredoxins 1 and 2 are more resistant to high levels of hydrogen peroxide, whereas they are more sensitive to diamide, a disulfide bond-inducing agent.
...
PMID:Thioredoxin 2 is involved in the oxidative stress response in Escherichia coli. 1064 6
Macrophages are a major target cell for HIV-1, and their infection contributes to HIV pathogenesis. We have previously shown that the cyclin-dependent kinase inhibitor p21 inhibits the replication of HIV-1 and other primate lentiviruses in human monocyte-derived macrophages by impairing reverse transcription of the viral genome. In the attempt to understand the p21-mediated restriction mechanisms, we found that p21 impairs HIV-1 and simian immunodeficiency virus (SIV)mac reverse transcription in macrophages by reducing the intracellular deoxyribonucleotide (dNTP) pool to levels below those required for viral cDNA synthesis by a SAM domain and HD domain-containing protein 1 (SAMHD1)-independent pathway. We found that p21 blocks dNTP biosynthesis by down-regulating the expression of the RNR2 subunit of
ribonucleotide reductase
, an enzyme essential for the reduction of ribonucleotides to dNTP. p21 inhibits RNR2 transcription by repressing E2F1 transcription factor, its
transcriptional activator
. Our findings unravel a cellular pathway that restricts HIV-1 and other primate lentiviruses by affecting dNTP synthesis, thereby pointing to new potential cellular targets for anti-HIV therapeutic strategies.
...
PMID:p21-mediated RNR2 repression restricts HIV-1 replication in macrophages by inhibiting dNTP biosynthesis pathway. 2483 97