No magnesium is needed for binding of the stimulator of interferon genes to cyclic dinucleotides

Stimulator of interferon genes (STING) binds cyclic dinucleotides (CDNs), which induce a large conformational change of the protein. The structural basis of activation of STING by CDNs is rather well understood. Unliganded STING forms an open dimer that undergoes a large conformational change ( ∼ 10   Å ) to a closed conformation upon the binding of a CDN molecule. This event activates downstream effectors of STING and subsequently leads to activation of the type 1 interferon response. However, a previously solved structure of STING with 3 ′ ,3 ′ -c-di-GMP shows Mg atoms mediating the interaction of STING with this CDN. Here, it is shown that no Mg atoms are needed for this interaction; in fact, magnesium can in some cases obstruct the binding of a CDN to STING.
Source: Acta Crystallographica Section F - Category: Biochemistry Authors: Tags: STING cGAS CDN 3 ′ ,3 -c-di-GMP crystal structure research communications Source Type: research

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Source: Advances in Immunology - Category: Allergy & Immunology Authors: Tags: Adv Immunol Source Type: research
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Source: Revista Brasileira de Epidemiologia - Category: Epidemiology Source Type: research
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Source: Chemical and Engineering News - Category: Chemistry Authors: Source Type: research
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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: ScienceNOW - Category: Science Authors: Tags: Immunology, Microbiology, Online Only r-articles Source Type: news
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Source: Radiation Research - Category: Physics Authors: Tags: Radiat Res Source Type: research
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