Related Experiment Video
Updated: Jan 8, 2026

Transmembrane Domain Oligomerization Propensity determined by ToxR Assay
Published on: May 26, 2011
Structural basis for ACT1 oligomerization induced by IL-17 receptor hetero-tetramer
Hui Zhang1, Xiao-Chen Bai2,3, Xuewu Zhang4,5
1Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
None:
The IL-17 receptors (IL-17Rs) play critical roles in immunity and inflammatory diseases. IL-17-induced heteromeric complexes between IL-17RA and another IL-17R trigger signaling by binding the downstream transducer ACT1 through interactions between their intracellular SEF/IL-17R (SEFIR) domains. The molecular mechanism of this process remains unclear. Here we present the cryo-EM structure of the complex of IL-17RA, IL-17RB and ACT1, showing that the IL-17RA and IL-17RB SEFIR domains form an asymmetric hetero-tetramer. The two IL-17RA SEFIR domains serve as the base to recruit ACT1, while IL-17RB stabilizes the IL-17RA dimer but makes no interaction with ACT1. IL-17RB, IL-17RA, and multiple ACT1 together form a double-stranded helical assembly. The C-terminal SEFIR extension (SEFEX) of IL-17RA acts as a molecular tendril to help anchor the ACT1 protomers. The structural model is supported by our mutational analyses. These findings reveal the basis for the formation for the signalosome of the IL-17 receptors and ACT1 critical for immune signaling.
Related Concept Videos
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Formation of Higher-order Actin Filaments
The high-order actin...
Mechanism of Filopodia Formation
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Generation of Straight or Branched Actin Filaments
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
The JAK-STAT Signaling Pathway
Intracellular Signaling Affects Focal Adhesions
Some...

