Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.3.14 (ATP synthase)
 7,042 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ethinyl estradiol (EE) is a strong hepatic promoter and weak complete hepatocarcinogen. Among the effects on rat liver caused by chronic exposure to non-hepatotoxic doses of EE is an initial, transient increase in hepatocyte growth followed by a subsequent inhibition (mitosuppression) of basal and/or induced liver growth. To investigate the mechanism of EE-induced mitosuppression, we performed a differential display and identified 10 genes whose expression was increased 2- to 4-fold in EE-induced, mitosuppressed livers (Chen et al., Carcinogenesis, 17, 2783-2786, 1996). We found that one of these clones was homologous to nuclear genome-encoded mitochondrial ATP synthase subunit E. Here, we describe the identification of two additional cDNAs representing transcripts whose levels were elevated during EE-induced mitosuppression as mitochondrial DNA-encoded cytochrome c oxidase subunit III and ATP synthase 6. In addition, we found that EE, estradiol and the estradiol catechol metabolites, 4-OH-estradiol and 2-OH-estradiol, increased the levels of these and other mitochondrial genome-encoded transcripts in human hepatoma HepG2 cells. We also observed that this increase can be blocked by inhibition of cytochrome P450-mediated estrogen metabolism, and that this increase is accompanied by increased mitochondrial superoxide production, which reflects increased respiratory chain activity.
 ...
PMID:Enhanced levels of several mitochondrial mRNA transcripts and mitochondrial superoxide production during ethinyl estradiol-induced hepatocarcinogenesis and after estrogen treatment of HepG2 cells. 988 77

A cDNA library constructed from kidney of the thirteen-lined squirrel, Spermophilus tridecemlineatus, was differentially screened for genes that were upregulated during hibernation. A clone encoding cytochrome c oxidase subunit 1 was found and confirmed to have been upregulated by northern blotting. Differential expression of Cox1 mRNA occurred in multiple organs during hibernation; in hibernating animals transcript levels were twofold higher in kidney and fourfold higher in heart and brown adipose tissue than in euthermic animals, but were unchanged in skeletal muscle. Transcript levels of mitochondrial-encoded ATP synthase 6/8 were similarly upregulated in these tissues whereas transcript levels of the nuclear encoded subunits Cox4 and ATP synthase alpha did not change during hibernation. Immunoblot analysis revealed a 2.4-fold increase in Cox 1 protein and a slight decrease in Cox 4 protein in kidney of hibernating squirrels, compared with euthermic controls. Hibernating mammals may increase the expression of the mitochondrial genome in general, and Cox1 specifically, to prevent or minimize the damage to the electron transport chain caused by the cold and ischemia experienced during a hibernation bout.
 ...
PMID:Differential expression of mitochondria-encoded genes in a hibernating mammal. 1200 Aug 7

Large areas of northern China have alkaline soil due to the accumulation of sodium carbonates (NaHCO3, Na2CO3). To understand better how plants can tolerate alkaline soil, a cDNA library was prepared from rice (Oryza sativa L.) roots grown in the presence of NaHCO3 stress. A cDNA clone isolated from this library was identified by a homology search as a mitochondrial ATP synthase 6 kDa subunit gene (RMtATP6; GenBank accession nos AB055076, BAB21526). In transformed yeast and tobacco protoplasts, the RMtATP6 protein was localized in mitochondria using the green fluorescent protein (GFP) marker. Analysis of RMtATP6 mRNA levels suggested that the expression of this gene was induced by stress from sodium carbonates and other sodium salts. Transgenic tobacco overexpressing the RMtATP6 gene had greater tolerance to salt stress at the seedling stage than untransformed tobacco. Among the other genes for F1F0-ATPase of rice, some were found to be up-regulated by some environmental stresses and some were not. These data suggest that the RMtATP6 protein acts as a subunit of ATP synthase, and is expressed in response to stress from several salts, with the other genes coding for the subunits of the same ATP-synthase.
 ...
PMID:Identification of a mitochondrial ATP synthase small subunit gene (RMtATP6) expressed in response to salts and osmotic stresses in rice (Oryza sativa L.). 1631 34