+データを開く
-基本情報
登録情報 | データベース: PDB / ID: 6gct | ||||||||||||||||||
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タイトル | cryo-EM structure of the human neutral amino acid transporter ASCT2 | ||||||||||||||||||
要素 | Neutral amino acid transporter B(0) | ||||||||||||||||||
キーワード | MEMBRANE PROTEIN (膜タンパク質) / neutral amino acid transporter | ||||||||||||||||||
機能・相同性 | 機能・相同性情報 glutamine secretion / L-glutamine import across plasma membrane / L-serine transmembrane transporter activity / glutamine transport / L-glutamine transmembrane transporter activity / ligand-gated channel activity / neutral amino acid transport / amino acid transmembrane transporter activity / Amino acid transport across the plasma membrane / neutral L-amino acid transmembrane transporter activity ...glutamine secretion / L-glutamine import across plasma membrane / L-serine transmembrane transporter activity / glutamine transport / L-glutamine transmembrane transporter activity / ligand-gated channel activity / neutral amino acid transport / amino acid transmembrane transporter activity / Amino acid transport across the plasma membrane / neutral L-amino acid transmembrane transporter activity / L-aspartate transmembrane transporter activity / L-aspartate import across plasma membrane / symporter activity / amino acid transport / antiporter activity / RHOJ GTPase cycle / RHOQ GTPase cycle / protein homotrimerization / RHOH GTPase cycle / transport across blood-brain barrier / RAC3 GTPase cycle / RAC1 GTPase cycle / basal plasma membrane / 赤血球形成 / メラノソーム / virus receptor activity / signaling receptor activity / extracellular exosome / 生体膜 / metal ion binding / 細胞膜 類似検索 - 分子機能 | ||||||||||||||||||
生物種 | Homo sapiens (ヒト) | ||||||||||||||||||
手法 | 電子顕微鏡法 / 単粒子再構成法 / クライオ電子顕微鏡法 / 解像度: 3.85 Å | ||||||||||||||||||
データ登録者 | Garaeva, A.A. / Oostergetel, G.T. / Gati, C. / Guskov, A. / Paulino, C. / Slotboom, D.J. | ||||||||||||||||||
資金援助 | オランダ, 5件
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引用 | ジャーナル: Nat Struct Mol Biol / 年: 2018 タイトル: Cryo-EM structure of the human neutral amino acid transporter ASCT2. 著者: Alisa A Garaeva / Gert T Oostergetel / Cornelius Gati / Albert Guskov / Cristina Paulino / Dirk J Slotboom / 要旨: Human ASCT2 belongs to the SLC1 family of secondary transporters and is specific for the transport of small neutral amino acids. ASCT2 is upregulated in cancer cells and serves as the receptor for ...Human ASCT2 belongs to the SLC1 family of secondary transporters and is specific for the transport of small neutral amino acids. ASCT2 is upregulated in cancer cells and serves as the receptor for many retroviruses; hence, it has importance as a potential drug target. Here we used single-particle cryo-EM to determine a structure of the functional and unmodified human ASCT2 at 3.85-Å resolution. ASCT2 forms a homotrimeric complex in which each subunit contains a transport and a scaffold domain. Prominent extracellular extensions on the scaffold domain form the predicted docking site for retroviruses. Relative to structures of other SLC1 members, ASCT2 is in the most extreme inward-oriented state, with the transport domain largely detached from the central scaffold domain on the cytoplasmic side. This domain detachment may be required for substrate binding and release on the intracellular side of the membrane. | ||||||||||||||||||
履歴 |
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-構造の表示
ムービー |
ムービービューア |
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構造ビューア | 分子: MolmilJmol/JSmol |
-ダウンロードとリンク
-ダウンロード
PDBx/mmCIF形式 | 6gct.cif.gz | 219 KB | 表示 | PDBx/mmCIF形式 |
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PDB形式 | pdb6gct.ent.gz | 181.2 KB | 表示 | PDB形式 |
PDBx/mmJSON形式 | 6gct.json.gz | ツリー表示 | PDBx/mmJSON形式 | |
その他 | その他のダウンロード |
-検証レポート
アーカイブディレクトリ | https://data.pdbj.org/pub/pdb/validation_reports/gc/6gct ftp://data.pdbj.org/pub/pdb/validation_reports/gc/6gct | HTTPS FTP |
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-関連構造データ
-リンク
-集合体
登録構造単位 |
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-要素
#1: タンパク質 | 分子量: 56638.902 Da / 分子数: 3 / 由来タイプ: 組換発現 / 由来: (組換発現) Homo sapiens (ヒト) / 遺伝子: SLC1A5, ASCT2, M7V1, RDR, RDRC / 発現宿主: Komagataella pastoris (菌類) / 参照: UniProt: Q15758 #2: 化合物 | |
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-実験情報
-実験
実験 | 手法: 電子顕微鏡法 |
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EM実験 | 試料の集合状態: PARTICLE / 3次元再構成法: 単粒子再構成法 |
-試料調製
構成要素 | 名称: human ASCT2 SLC1A5 / タイプ: COMPLEX / 詳細: human ASCT2 SLC1A5 / Entity ID: #1 / 由来: RECOMBINANT |
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分子量 | 値: 0.172 MDa / 実験値: YES |
由来(天然) | 生物種: Homo sapiens (ヒト) |
由来(組換発現) | 生物種: Komagataella pastoris (菌類) |
緩衝液 | pH: 7 詳細: 20mM Tris-HCl pH 7.4 300mM NaCl 1mM L-glutamine 0.05% DDM 0.005% CHS |
試料 | 濃度: 2.5 mg/ml / 包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES |
試料支持 | グリッドの材料: GOLD / グリッドのサイズ: 200 divisions/in. / グリッドのタイプ: Quantifoil, UltrAuFoil, R1.2/1.3 |
急速凍結 | 装置: FEI VITROBOT MARK II / 凍結剤: ETHANE / 湿度: 100 % / 凍結前の試料温度: 278 K |
-電子顕微鏡撮影
実験機器 | モデル: Talos Arctica / 画像提供: FEI Company |
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顕微鏡 | モデル: FEI TALOS ARCTICA |
電子銃 | 電子線源: FIELD EMISSION GUN / 加速電圧: 200 kV / 照射モード: FLOOD BEAM |
電子レンズ | モード: BRIGHT FIELDBright-field microscopy / 倍率(公称値): 49407 X / 倍率(補正後): 49407 X / 最大 デフォーカス(公称値): 2.5 nm / 最小 デフォーカス(公称値): 0.4 nm / Calibrated defocus min: 0.4 nm / 最大 デフォーカス(補正後): 2.5 nm / Cs: 2.7 mm / C2レンズ絞り径: 100 µm / アライメント法: COMA FREE |
試料ホルダ | 凍結剤: NITROGEN 試料ホルダーモデル: FEI TITAN KRIOS AUTOGRID HOLDER 最高温度: 90 K / 最低温度: 70 K |
撮影 | 平均露光時間: 9 sec. / 電子線照射量: 0.87 e/Å2 / 検出モード: COUNTING フィルム・検出器のモデル: GATAN K2 SUMMIT (4k x 4k) 詳細: Freshly purified protein was concentrated using Vivaspin concentrating devices with a molecular weight cutoff of 100kDa to 2-2.5 mg ml-1. 2.8 ul were applied on holey-carbon cryo-EM grids ...詳細: Freshly purified protein was concentrated using Vivaspin concentrating devices with a molecular weight cutoff of 100kDa to 2-2.5 mg ml-1. 2.8 ul were applied on holey-carbon cryo-EM grids (Quantifoil Au R1.2-1.3, 200 and 300 mesh), which were prior glow-discharged at 5 mA for 20 s. Grids were blotted for 3-5 s in a Vitrobot (Mark 3, Thermo Fisher) at 20C temperature and 100% humidity, subsequently plunge-frozen in liquid ethane and stored in liquid nitrogen. Cryo-EM data were collected on a 200 keV Talos Arctica microscope (Thermo Fisher) using a post-column energy filter (Gatan) in zero-loss mode, using a 20 eV slit, a 100 um objective aperture, in an automated fashion using EPU software (Thermo Fisher) on a K2 summit detector (Gatan) in counting mode. Cryo-EM images were acquired at a pixel size of 1.012A (calibrated magnification of 49,407x), a defocus range from -0.4 to 2.5 um, an exposure time of 9 sec and a sub-frame exposure time of 150 ms (60 frames), and a total electron dose on the specimen level of about 52 electrons per A2. Best regions on the grid were screened with a self-written script to calculate the ice thickness and data quality was monitored on the fly using the software FOCUS |
電子光学装置 | エネルギーフィルター名称: GIF Quantum LS / エネルギーフィルター 上限: 20 eV / エネルギーフィルター 下限: 0 eV |
画像スキャン | 動画フレーム数/画像: 60 / 利用したフレーム数/画像: 1-60 |
-解析
ソフトウェア | 名称: PHENIX / バージョン: 1.13_2998: / 分類: 精密化 | ||||||||||||||||||||||||||||||||
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EMソフトウェア |
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CTF補正 | タイプ: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||||||||||
対称性 | 点対称性: C3 (3回回転対称) | ||||||||||||||||||||||||||||||||
3次元再構成 | 解像度: 3.85 Å / 解像度の算出法: FSC 0.143 CUT-OFF / 粒子像の数: 184080 詳細: A total of 6345 dose-fractionated cryo-EM images were recorded and subjected to motion-correction and dose-weighting of frames by MotionCor2. The CTF parameters were estimated on the movie ...詳細: A total of 6345 dose-fractionated cryo-EM images were recorded and subjected to motion-correction and dose-weighting of frames by MotionCor2. The CTF parameters were estimated on the movie frames by ctffind4.1. Bad images showing contamination, a defocus below or above 0.4 and -3um or a bad CTF estimation were discarded, resulting in 4863 images used for further analysis with the software package RELION2.1. About 3000 particles were picked manually to generate 2D references which where improved in several rounds of autopick. A low threshold was used during the final autopick step to ensure that no particles are missed yielding more than a million particles. Particles were extracted with a box size of 240 pixels, and initial classification steps were performed with three-fold binned data. False positives or bad particles were removed in first rounds of 2D classification, resulting in 628,015 particles that were further sorted in several rounds of 3D classification. A map generated from the GltPh structure (PDB ID 3KBC) was used as reference for the first round, and the best output class was used in subsequent jobs in an iterative way. The best 3D class, comprising 184,080 particles from 4859 images, was subjected to auto-refinement, yielding a map with a resolution of 4.26 A before masking and 3.91 A after masking. Particles were further polished in RELION version 2.1 and subjected to another round of 2D and 3D classification resulting in a final dataset of 133,437 particles. The final polished map had a resolution of 4.26 A before masking and 3.85 A after masking. The map was sharpened using an isotropic B-factor of -171 A2, for manual inspection a B-factor of -225 A2 was used. The approach of focused refinement, where the less-resolved detergent micelle was subtracted from the particle images, did not improve resolution. During 3D classification and auto-refinement jobs a C3-symmetry was imposed. To check for conformational heterogeneity of the data, where single protomers within the trimer might adopt a different conformation, 3D classifications with no symmetry imposed were performed at different stages of image processing. We further performed 3D classification on the individual protomers of a single transporter using symmetry expansion and signal subtraction. Both approaches showed no indication of the existence of a different conformation. Local resolution estimates were estimated by RELION. All resolutions were estimated using the 0.143 cut-off criterion with gold-standard Fourier shell correlation (FSC) between two independently refined half maps. During post-processing, the approach of high-resolution noise substitution was used to correct for convolution effects of real-space masking on the FSC curve. 対称性のタイプ: POINT | ||||||||||||||||||||||||||||||||
原子モデル構築 | プロトコル: AB INITIO MODEL / 空間: REAL | ||||||||||||||||||||||||||||||||
拘束条件 |
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