Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Objectives</jats:title><jats:p>To investigate the functional consequences of the single nucleotide polymorphism <jats:italic>rs4648889</jats:italic> in a putative enhancer upstream of the <jats:italic>RUNX3</jats:italic> promoter strongly associated with ankylosing spondylitis (AS).</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>The effects of <jats:italic>rs4648889</jats:italic> on transcription factor (TF) binding were tested by DNA pull-down and quantitative mass spectrometry. The results were validated by electrophoretic mobility gel shift assays (EMSA), Western blot (WB) analysis of the pulled-down eluates, and chromatin immuno-precipitation (ChIP)-qPCR.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Several TFs showed differential allelic binding to a 50bp DNA probe spanning <jats:italic>rs4648889</jats:italic>. Binding was increased to the AS-risk A allele for IKZF3 (<jats:italic>aiolos</jats:italic>) in nuclear extracts from CD8+ T-cells (3.7-fold, p&lt;0.03) and several components of the NUcleosome Remodeling Deacetylase (NuRD) complex, including Chromodomain-Helicase-DNA-binding protein 4 (3.6-fold, p&lt;0.05) and Retinoblastoma-Binding Protein 4 (4.1-fold, p&lt;0.02). In contrast, binding of interferon regulatory factor (IRF) 5 was increased to the AS-protective G allele. These results were confirmed by EMSA, WB and ChIP-qPCR.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>The association of AS with <jats:italic>rs4648889</jats:italic> most likely results from its influence on the binding of this enhancer-like region to TFs, including IRF5, IKZF3 and members of the NuRD complex. Further investigation of these factors and RUNX3-related pathways may reveal important new therapeutic possibilities in AS.</jats:p></jats:sec>

Original publication




Journal article


Cold Spring Harbor Laboratory

Publication Date