Research Highlights

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  • Cell & molecular biology

Published online: 1 February 2012 | doi:10.1038/nchina.2012.9

Molecular biology: Cutting the ties that bind

Edward Duca

Introduction

© (2011) Nature

In humans, the protein NF-κB activates the immune system against bacterial infection. To overcome the body's defenses, certain bacteria shut down NF-κB activation by injecting the virulent factor NleE directly into cells. Feng Shao at the National Institute of Biological Sciences in Beijing and co-workers¹ have now uncovered the mechanism by which NleE blocks NF-κB.

The researchers found that NleE physically binds to TAB2 and TAB3 — two of the proteins involved in NF-κB activation — and then adds methyl groups to two of their cysteine residues (pictured). This modification causes zinc ions to dissociate from TAB2 and TAB3, which prevents the zinc-finger domains in TAB2 and TAB3 from binding to other proteins involved in NF-κB activation.

Zinc-finger domains are found in a variety of signaling pathways — not only in NF-κB activation. The researchers suggest that the dissociation of zinc ions could be a widespread mechanism for pathogenic bacteria to control host molecules, and may represent a new target for anti-bacterial drugs.

The authors of this work are from:
Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; National Institute of Biological Sciences, Beijing, China.

Reference

1. Zhang, L. et al. Cysteine methylation disrupts ubiquitin-chain sensing in NF-κB activation. Nature doi:10.1038/nature10690 (2011). | Article | OpenURL