How to Manipulate Cellular O2 Sensing

How to manipulate truthful prior-dependent mechanisms?

In the standard formulation of mechanism design, a key assumption is that the designer has reliable information and technology to determine a prior distribution over types of the agents. In the meanwhile, as pointed out by the Wilson’s Principle, a mechanism should reply as little as possible on the accuracy of prior type distribution. In this paper, we put forward a simple model to formalize a...

How Hard is it to Manipulate Voting ?

How O2 Binds to Heme

We have used density functional methods to calculate fully relaxed potential energy curves of the seven lowest electronic states during the binding of O2 to a realistic model of ferrous deoxyheme. Beyond a Fe–O distance of 2.5 Å, we find a broad crossing region with five electronic states within 15 kJ/mol. The almost parallel surfaces strongly facilitate spin inversion, which is necessary in th...

Cellular adaptation to hypoxia: O2-sensing protein hydroxylases, hypoxia-inducible transcription factors, and O2-regulated gene expression.

Although it was known for a long time that oxygen deprivation leads to the transcriptional induction of the gene encoding erythropoietin, the molecular mechanisms behind this process remained enigmatic. The cloning of the hypoxia-inducible factors (HIFs), the finding that HIF-1 regulates the expression of many more genes apart from erythropoietin, and the elucidation of the oxygen-dependent mec...

O2 Sensing: Only Skin Deep?

The transcription factor HIF-1 mediates adaptive responses to hypoxia, and its activity is negatively regulated by O2-dependent binding of the von Hippel-Lindau (VHL) protein. In this issue, Boutin et al. (2008) use conditional knockout mice to demonstrate that sensing of O2 by keratinocytes in the epidermis leads to alterations in cutaneous blood flow that affect the production of the hormone ...