Article

The peptidyl-prolyl isomerase Pin1 regulates the stability of granulocyte-macrophage colony-stimulating factor mRNA in activated eosinophils.

The Waisman Center for Developmental Disabilities, the Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine, Madison, Wisconsin 53705, USA.
Nature Immunology (Impact Factor: 24.97). 01/2006; 6(12):1280-7. DOI: 10.1038/ni1266
Source: PubMed

ABSTRACT The infiltration, accumulation and degranulation of eosinophils in the lung represents a hallmark of active asthma. In vivo or in vitro eosinophil activation triggers the secretion of the antiapoptotic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). We now identify Pin1, a cis-trans isomerase, as an essential component of the ribonucleoprotein complex responsible for GM-CSF mRNA stabilization, cytokine secretion and the survival of activated eosinophils. Pin1 regulated the association of the AU-rich element-binding proteins AUF1 and hnRNP C with GM-CSF mRNA, accelerating or slowing decay, respectively. These data indicate Pin1 is a key mediator of GM-CSF production.

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