9O5A

The KICSTOR-GATOR1 complex

9O5A の概要

• エントリーDOI: 10.2210/pdb9o5a/pdb
• EMDBエントリー: 70135
• 分子名称: GATOR complex protein NPRL2, GATOR1 complex protein DEPDC5, KICSTOR complex protein SZT2, ... (7 entities in total)
• 機能のキーワード: lysosome, gator1, kicstor, cell growth, amino acid sensing, mtor, kptn, itfg2, c12orf66, szt2, nprl2, nprl3, depdc5, cell cycle
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 7
• 化学式量合計: 829223.91

構造登録者

Bayly-Jones, C.,Lupton, C.J.,Chang, Y.G.,Ellisdon, A.M. (登録日: 2025-04-09, 公開日: 2026-02-18)

主引用文献

Lupton, C.J.,Bayly-Jones, C.,Dong, S.,Lam, T.,Luo, W.,Jones, G.D.,Mastos, C.,Frescher, N.J.,Lim, S.S.,Keen, A.C.,Formosa, L.E.,Venugopal, H.,Chang, Y.G.,Halls, M.L.,Ellisdon, A.M.
Structure of the lysosomal KICSTOR-GATOR1-SAMTOR nutrient-sensing supercomplex.
Cell, 2026

PubMed Abstract: The guanosine triphosphate (GTP)-bound state of the heterodimeric Rag GTPases functions as a molecular switch regulating mechanistic target of rapamycin complex 1 (mTORC1) activation at the lysosome downstream of amino acid fluctuations. Under low amino acid conditions, GTPase-activating protein (GAP) activity toward Rags 1 (GATOR1) promotes RagA GTP hydrolysis, preventing mTORC1 activation. KICSTOR recruits and regulates GATOR1 at the lysosome by undefined mechanisms. Here, we resolve the KICSTOR-GATOR1 structure, revealing a striking ∼60-nm crescent-shaped assembly. GATOR1 anchors to KICSTOR via an extensive interface, and mutations that disrupt this interaction impair mTORC1 regulation. The S-adenosylmethionine sensor SAMTOR binds KICSTOR in a manner incompatible with metabolite binding, providing structural insight into methionine sensing via SAMTOR-KICSTOR association. We discover that KICSTOR and GATOR1 form a dimeric supercomplex. This assembly restricts GATOR1 to an orientation that favors the low-affinity active GAP mode of Rag GTPase engagement while sterically restricting access to the high-affinity inhibitory mode, consistent with a model of an active lysosomal GATOR1 docking complex.

PubMed: 41512879
DOI: 10.1016/j.cell.2025.12.005

実験手法

ELECTRON MICROSCOPY (3.2 Å)