EMDB/PDB/SASBDBから引用されている文献のデータベース

キーワード
構造解析手法	All X線回折 NMR 電子顕微鏡小角散乱中性子線回折線維回折粉末回折赤外分光 EPR FRET 理論モデルハイブリッド
著者・登録者
ジャーナル
IF	>30 >20 >10 >5 all

タイトル	Nucleotide-dependent conformational changes direct peptide export by the transporter associated with antigen processing.
ジャーナル・号・ページ	Immunity, Vol. 58, Issue 9, Page 2166-22175.e4, Year 2025
掲載日	2025年9月9日
著者	James Lee / Victor Manon / Jue Chen /
PubMed 要旨	The transporter associated with antigen processing (TAP) delivers peptide antigens from the cytoplasm into the endoplasmic reticulum (ER) for loading onto major histocompatibility complex class I ...The transporter associated with antigen processing (TAP) delivers peptide antigens from the cytoplasm into the endoplasmic reticulum (ER) for loading onto major histocompatibility complex class I (MHC-I) molecules. To examine the mechanisms of peptide transport and release into the ER, we determined cryo-electron microscopy structures of the human TAP heterodimer in multiple functional states along the transport cycle. In the inward-facing conformation, when the peptide translocation cavity within the TAP heterodimer is exposed to the cytosol, ATP binding strengthened intradomain assembly. Transition to the outward-facing conformation, when the transporter opens to the ER lumen, led to a complete reconfiguration of the peptide-binding site, facilitating peptide release. ATP hydrolysis opened the catalytically active nucleotide-binding consensus site, and the subsequent separation of the nucleotide-binding domains reset the transport cycle. These findings establish a comprehensive structural framework for understanding unilateral peptide transport, vanadate trapping, and trans-inhibition-an internal feedback mechanism that prevents excessive peptide accumulation and activation of the ER stress response.
リンク	Immunity / PubMed:40885191 / PubMed Central
手法	EM (単粒子)
解像度	3.1 - 3.7 Å
構造データ	49045 9n61 EMDB-49045, PDB-9n61: Transporter associated with antigen processing (TAP) bound to the 9-mer peptide RRYQKSTEL and ATP 手法: EM (単粒子) / 解像度: 3.6 Å 49046 9n62 EMDB-49046, PDB-9n62: Transporter associated with antigen processing (TAP) EQ mutant bound to ATP in the inward-facing state 手法: EM (単粒子) / 解像度: 3.4 Å 49047 9n63 EMDB-49047, PDB-9n63: Transporter associated with antigen processing (TAP) EQ mutant bound to ATP in the outward-facing open state 手法: EM (単粒子) / 解像度: 3.1 Å 49048 9n64 EMDB-49048, PDB-9n64: Transporter associated with antigen processing (TAP) EQ mutant bound to ATP in the outward-facing kinked state 手法: EM (単粒子) / 解像度: 3.7 Å 49049 9n65 EMDB-49049, PDB-9n65: Transporter associated with antigen processing (TAP) bound to ATP and ADP In the inward-facing conformation 手法: EM (単粒子) / 解像度: 3.7 Å 49050 9n66 EMDB-49050, PDB-9n66: Transporter associated with antigen processing (TAP) bound to ATP and ADP in the outward-facing open state 手法: EM (単粒子) / 解像度: 3.2 Å
化合物	ChemComp-ATP: ADENOSINE-5'-TRIPHOSPHATE / ATP, エネルギー貯蔵分子YM ChemComp-MG: Unknown entry ChemComp-HOH: WATER ChemComp-ADP: ADENOSINE-5'-DIPHOSPHATE / ADP, エネルギー貯蔵分子YM
由来	homo sapiens (ヒト)
キーワード	MEMBRANE PROTEIN / ABC transporter / antigen processing / peptide transporter