9Q1F

Choanoflagellate Salpingoeca macrocollata STING

9Q1F の概要

• エントリーDOI: 10.2210/pdb9q1f/pdb
• 分子名称: Endolysin,Stimulator of interferon genes, cGAMP (3 entities in total)
• 機能のキーワード: innate immunity, cyclic dinucleotide signaling, stimulator of interferon genes, cgas-sting, immune system
• 由来する生物種: Salpingoeca macrocollata; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 84996.02

構造登録者

Toyoda, H.C.,Li, Y.,Kranzusch, P.J. (登録日: 2025-08-13, 公開日: 2025-10-01)

主引用文献

Li, Y.,Toyoda, H.C.,Fernandez, S.G.,Tiwari, B.,McNairy, C.,Woznica, A.,Kranzusch, P.J.
A choanoflagellate cGLR-STING pathway reveals evolutionary links between bacterial and animal immunity.
Biorxiv, 2025

PubMed Abstract: Animal innate immunity evolved from ancient pathways in bacterial anti-phage defense. How bacterial immune components were first acquired and adapted within eukaryotic cells remains poorly understood. Here we identify a complete cGLR-STING signaling axis in choanoflagellates, the closest living relatives of animals, that exhibits a mosaic of features from both bacterial and animal immunity. Comparative genomics reveals choanoflagellate and genes organized in operon-like arrangements reminiscent of bacterial defense loci. Reconstitution of choanoflagellate cGLR-STING signaling demonstrates that activation occurs through the conserved nucleotide immune signal 2'3'-cGAMP. Structural analysis of a choanoflagellate STING-2'3'-cGAMP complex explains how retention of bacterial-like features in early eukaryotic proteins shapes ligand specificity and receptor activation. We analyze and evolution in unicellular eukaryotes and identify further STING homologs in choanoflagellates and fungi that support additional independent acquisition events. Our results reveal molecular fossils that bridge bacterial and animal immunity and illuminate early eukaryotic immune system evolution.

PubMed: 40950183
DOI: 10.1101/2025.09.04.674280

実験手法

X-RAY DIFFRACTION (2.65 Å)