+検索条件
-Structure paper
| タイトル | Ancestral Chaperonins Provide the First Structural Glimpse into Early Multimeric Protein Evolution. |
|---|---|
| ジャーナル・号・ページ | Mol Biol Evol, Vol. 42, Issue 12, Year 2025 |
| 掲載日 | 2025年11月28日 |
著者 | Rita Severino / Jorge Cuéllar / Jorge Gutiérrez-Seijo / Moisés Maestro-López / Luis Sánchez-Pulido / César Santiago / Mercedes Moreno-Paz / José María Valpuesta / Víctor Parro / ![]() |
| PubMed 要旨 | Chaperonins are essential protein-folding machines, classified into three structural and phylogenetic groups: Group I (bacterial GroEL), Group II (archaeal thermosome and eukaryotic CCT), and Group ...Chaperonins are essential protein-folding machines, classified into three structural and phylogenetic groups: Group I (bacterial GroEL), Group II (archaeal thermosome and eukaryotic CCT), and Group III (bacterial thermosome-like). Using ancestral sequence reconstruction (ASR) and protein resurrection, we inferred and experimentally characterized the last common ancestors of these groups (ancestral chaperonins ACI, ACII, and ACIII). The resurrected proteins exhibited ATPase activity (except ACII) and protected client proteins from heat-induced inactivation. Structural analyses by electron microscopy and Cryo-EM revealed that ACI forms single 7-mer rings, whereas ACII adopts a mixed population of single/double 8-mer rings, representing the first experimental observation of intermediate oligomeric states. ACII also features a unique cochaperonin-independent closure mechanism, distinct from modern Group I and II chaperonins. Together, these findings provide the experimental structural reconstruction of the most ancient and complex multimeric proteins so far, uncover novel intermediate states in chaperonin evolution, and offer a direct empirical framework for studying the emergence of multimeric complexity in early cellular life. |
リンク | Mol Biol Evol / PubMed:41310978 / PubMed Central |
| 手法 | EM (単粒子) |
| 解像度 | 3.21 - 8.21 Å |
| 構造データ | EMDB-54339, PDB-9rwp: EMDB-54340, PDB-9rwq: EMDB-54341, PDB-9rwr: ![]() EMDB-54342: 3D Reconstruction of Ancestral Group I Chaperonin (ACI) Single-Ring ![]() EMDB-54343: 3D Reconstruction of Ancestral Group II Chaperonin (ACII) Double-Ring in Open Conformation ![]() EMDB-54344: 3D Reconstruction of Ancestral Group II Chaperonin (ACII) Single-Ring in Closed Conformation ![]() EMDB-54345: 3D Reconstruction of Ancestral Group II Chaperonin (ACII) Single-Ring in Open Conformation |
| 化合物 | ![]() ChemComp-ADP: ![]() ChemComp-MG: |
| 由来 |
|
キーワード | CHAPERONE / Chaperonins / Ancestors / Evolution / Cryoelectron Microscopy |
ムービー
コントローラー
構造ビューア
万見文献について



著者
リンク












キーワード