Learn More
HIF-1alpha is believed to promote tumor growth and metastasis, and many efforts have been made to develop new anticancer agents based on HIF-1alpha inhibition. YC-1 is a widely used HIF-1alpha inhibitor both in vitro and in vivo, and is being developed as a novel class of anticancer drug. However, little is known about the mechanism by which YC-1 degrades(More)
Runt-related transcription factor 2 (Runx2) transactivates many genes required for osteoblast differentiation. The role of N-α-acetyltransferase 10 (NAA10, arrest-defective-1), originally identified in yeast, remains poorly understood in mammals. Here we report a new NAA10 function in Runx2-mediated osteogenesis. Runx2 stabilizes NAA10 in osteoblasts during(More)
Hepcidin, a liver peptide, systemically inhibits iron utilization and is downregulated under hypoxic conditions. However, little is known about the mechanism underlying the hypoxic suppression of hepcidin. Here, we tested the possibility that HIF-1 and ROS are involved in hepcidin regulation. Hepcidin mRNA, pre-mRNA, and protein levels were reduced in mouse(More)
A putative cellular function of tetrahydropteridines (l-erythro-tetrahydrobiopterin and d-threo-tetrahydrobiopterin) was investigated in Dictyostelium discoideum Ax2 using a mutant disrupted in the gene encoding sepiapterin reductase (SR). The SR mutant, which produces about 3% of tetrahydropteridines if compared to wild-type, was elucidated to have several(More)
Rheumatoid arthritis (RA) is known to be associated with increased risks of hypoxia-related diseases, whose progresses are critically determined by HIF-1alpha. The authors hypothesized that the hypoxia-related complications of RA are associated with HIF-1alpha deregulation by some factor(s) in RA serum. Arthritis was induced in female Lewis rats by(More)
Hypoxic inhibition of K+ current is a critical O2-sensing mechanism. Previously, it was demonstrated that the cooperative action of TASK-1 and NADPH oxidase-4 (NOX4) mediated the O2-sensitive K+ current response. Here we addressed the O2-sensing mechanism of NOX4 in terms of TASK-1 regulation. In TASK-1 and NOX4-coexpressing human embryonic kidney 293(More)
The quantitative determination of tetrahydrobiopterin (BH4) and its oxidized forms (dihydrobiopterin and biopterin) is important in searching for possible markers of neuropsychiatric and cardiovascular disorders as well as in diagnosing BH4 deficiencies. Currently, two high-performance liquid chromatography (HPLC) methods are available, although both have(More)
We have studied the regulatory function of Dictyostelium discoideum Ax2 phenylalanine hydroxylase (dicPAH) via characterization of domain structures. Including the full-length protein, partial proteins truncated in regulatory, tetramerization, or both, were prepared from Escherichia coli as his-tag proteins and examined for oligomeric status and catalytic(More)
Here, we report cloning of cyanobacterial genes encoding pteridine glycosyltransferases that catalyze glucosyl or xylosyl transfer from UDP-sugars to tetrahydrobiopterin. The genes were cloned by PCR amplification from genomic DNA which was isolated from culture and environmental samples and overexpressed in Escherichia coli for an in vitro activity assay.