Fresh twist in a biochemical whodunnit

The authors found that incubation of PKG1a with cis-WOOH or with tryptophan in the presence of IDO1 induces the formation of the disulfide bond. [...]vasodilation of blood vessels isolated from a mouse model of sepsis - endotoxaemic mice, in which the animals are exposed to bacteria-derived toxins - was suppressed when the animals expressed a mutant version of PKGla that could not dimerize at Cys 42 on exposure to oxidants. The authors then observed that upregulation and activation of IDO1 in a mouse model of atherosclerosis (an inflammatory disease that is characterized by narrowing of blood vessels) contributes to tryptophanmediated vasodilation and blood-pressure control, which suggests that IDO1 could be a target in efforts to develop treatments for inflammatory diseases. Perhaps, although several other approaches are also possible, given that many vasodilating factors are involved in systemic inflammation. [...]IDO1 has many crucial roles in immune cells, so its inhibition is likely to have several effects. Stanley and colleagues found that levels of IDO1 in heart-muscle tissue in mice were undetectable during pressure overload, but rose markedly in response to administration of interferon-? (a protein that is involved in many inflammatory responses), which suggests a role for IDO1-generated cis-WOOH in inflammatory conditions of the heart.