1。脳ミトコンドリア単離（ ブラウンMRらから適応。9） <ol><li>インスティテューショナルアニマルケアと使用委員会（IACUC）によって承認された方法を用いてラットを生け贄に捧げる。 </li><li>断頭により、動物の頭をカットし、皮膚をカットし、頭蓋骨を公開します。 </li><li>はさみや骨鉗子で切断してそっと頭蓋骨を開きます。脳を取り外します。 </li><li>分離バッファにおける小脳（ 表1を参照）することなく、細かく脳をミンチし、5ミリリットルガラス/テフロンホモジナイザー（機器リストを参照）に転送します。 </li><li>そっとティッシュをホモジナイズ10回（無気泡）、約5分。 </li><li> 4時10分°Cベンチトップ遠心分離機で用1,500×gでサンプルを遠心分離します。 </li><li>上清を保存（ミトコンドリアとシナプトソーム）とペレット（核物質と細胞の破片）を捨てる。ベンチトップ遠心分離機で4℃で10分間、16,000×gで遠心分離します。 </li><li>捨てるアイソレーションバッファー500μlの上清と再懸濁ペレット。細胞破砕容器（機器リストを参照）シナプトソームを乱す。急減圧が続く10分間のために1,200 PSIの圧力を適用します。 </li><li> 126500で層フィコール勾配上に混合物（ 表2参照）、SW-50.1ローターと遠心で行わ×gで4℃で20分間遠心°におけるC（機器リストを参照してください）。ペレットを精製ミトコンドリアで、フィコールの異なる密度の間の層は未破砕シナプトソームです。 </li><li> 4時10分°ベンチトップ遠心分離機でC用16,000×gで分離バッファに遠心分離によってペレットを洗浄。 </li></ol> 2。亜ミトコンドリアの小胞（SMV）アイソレーション（チャンら 10から適応） <ol><li> 1％ジギトニン等量と組み合わせる200μlのアイソレーション·バッファ内のミトコンドリア再懸濁、15分間氷の上に座ることができます。 </li><li>より多くのアイソレーションバフを追加16,000でERと遠心×4 gで10分間°ベンチトップ遠心分離機でC。これを2回行う。 </li><li> 200μlのアイソレーションバッファーでペレットを再懸濁すると10％Lubrol PX（C12E​​9）2μlのを追加します。混ぜ、15分間氷上で座ることができます。 </li><li>分離バッファ上に層混合物、182,000でSW-50.1ローター遠心×4のG℃で1時間で場所。 </li><li> 4℃で10分間16,000で分離バッファで卓上遠心×gでの遠心分離することにより最終的に得られたペレットを洗浄します</li></ol> 3。電気生理学的記録<ol><li>典型的な電気生理学リグは、増幅器、pClamp10.0ソフトウェア、マニピュレータ、顕微鏡、防振台、ファラデーケージと一緒にDigidata 1440Aアナログ - デジタル変換器インタフェースを備えたPCのコンピュータを含む。 </li><li>ホウケイ酸ガラスキャピラリーチューブはフレーミング/ブラウンマイクロピペットプラーモデルP-87に挿入されます。ピペットプラープログラムに最適化されていますMΩ80〜100の間に抵抗とピペットを生成します。 </li><li> SMVs生理的細胞内液（ATP、記録中に適切な時間に加算されます）（ 表3）に配置されます。パッチクランプピペットは、同じ溶液（無ATP）が充填されている。レコーディングを室温でSMVsにギガオームシールを形成することによって作られる。小胞はニコン又はツァイス倒立顕微鏡と位相差顕微鏡によって可視化される。 </li><li>膜電位は、-100 mVでから10秒の期間で+は100mVの範囲の電圧で維持される。録音はアンプ回路を使用して5 kHzでフィルタリングされます。 1未満の浮遊pAの電気的又は非特異的なノイズのレベルが成功記録のために望ましい。 </li><li>データは、単一チャネル·イベントの周波数と振幅を決定するために、例えばClampfit 10.0ソフトウェアを使用して分析される。電圧依存性は、直流電圧の関係をプロットすることによって決定される。 </li></ol>

<ol>
	<li>Cheng, W. C., Berman, S. B., Ivanovska, I., Jonas, E. A., Lee, S. J., Chen, Y., Kaczmarek, L. K., Pineda, F., Hardwick, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+factors+with+dual+roles+in+death+and+survival.">Mitochondrial factors with dual roles in death and survival.</a> Oncogene. 25, 4697-4705 (2006).</li><li>Duchen, M. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondria+and+calcium+in+health+and+disease.">Mitochondria and calcium in health and disease.</a> Cell Calcium. 44, 1-5 (2008).</li><li>Lemasters, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulation+of+mitochondrial+membrane+permeability+in+pathogenesis,+autophagy+and+control+of+metabolism.">Modulation of mitochondrial membrane permeability in pathogenesis, autophagy and control of metabolism.</a> J. Gastroenterol. Hepatol. 22, S31-S37 (2007).</li><li>Cox, G. B., Jans, D. A., Fimmel, A. L., Gibson, F., Hatch, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypothesis.+The+mechanism+of+ATP+synthase.+Conformational+change+by+rotation+of+the+beta-subunit.">Hypothesis. The mechanism of ATP synthase. Conformational change by rotation of the beta-subunit.</a> Biochim. Biophys. Acta. 768, 201-208 (1984).</li><li>Cox, G. B., Fimmel, A. L., Gibson, F., Hatch, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanism+of+ATP+synthase:+a+reassessment+of+the+functions+of+the+b+and+a+subunits.">The mechanism of ATP synthase: a reassessment of the functions of the b and a subunits.</a> Biochim. Biophys. Acta. 849, 62-69 (1986).</li><li>Cory, S., Huang, D. C., Adams, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Bcl-2+family:+roles+in+cell+survival+and+oncogenesis.">The Bcl-2 family: roles in cell survival and oncogenesis.</a> Oncogene. 22, 8590-8607 (2003).</li><li>Vander Heiden, M. G., Thompson, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bcl-2+proteins:+regulators+of+apoptosis+or+of+mitochondrial+homeostasis.">Bcl-2 proteins: regulators of apoptosis or of mitochondrial homeostasis.</a> Nat. Cell Biol. 1, 209-216 (1999).</li><li>Alavian, K. N., Li, H., Collis, L., Bonanni, L., Zeng, L., Sacchetti, S., Lazrove, E., Nabili, P., Flaherty, B., Graham, M., Chen, Y., Messerli, S. M., Mariggio, M. A., Rahner, C., McNay, E., Shore, G. C., Smith, P. J. S., Hardwick, J. M., Jonas, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bcl-xL+regulates+metabolic+efficiency+of+neurons+through+interaction+with+the+mitochondrial+F1FO+ATP+synthase.">Bcl-xL regulates metabolic efficiency of neurons through interaction with the mitochondrial F1FO ATP synthase.</a> Nat. Cell Biol. 13 (10), 1224-1233 (2011).</li><li>Brown, M. R., Sullivan, P. G., Dorenbos, K. A., Modafferi, E. A., Geddes, J. W., Steward, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitrogen+disruption+of+synaptoneurosomes:+an+alternative+method+to+isolate+brain+mitochondria.">Nitrogen disruption of synaptoneurosomes: an alternative method to isolate brain mitochondria.</a> Journal of Neuroscience Methods. 137, 299-303 (2004).</li><li>Chan, T. L., Greenawalt, J. W., Pedersen, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+ultrastructural+properties+of+a+mitochondrial+inner+membrane+fraction+deficient+in+outer+membrane+and+matrix+activities.">Biochemical and ultrastructural properties of a mitochondrial inner membrane fraction deficient in outer membrane and matrix activities.</a> J. Cell Biol. 45 (2), 291-305 (1970).</li><li>Young, H. K. o., Delannoy, M., Hullihen, J., Chiu, W., Pedersen, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+ATP+Synthasomes.">Mitochondrial ATP Synthasomes.</a> J. Biol. Chem. 278 (14), 12305-12309 (2003).</li></ol>

利害の衝突は宣言されていない。

この方法によってphenotypes.SMVspurified細胞の区別なく全脳から、手順2の後にここに、ステップ1の終了時に純粋なミトコンドリアの分離を可能にし、亜ミトコンドリアの小胞（SMVs）に記載された方法は、に示されているように他の細胞内小器官による汚染の本質的に自由である図1に、私たちの前の仕事（Alavian KN ら 8）、凍結前にその構造と機能の整合性を保持しま?...

<table><tbody><tr><td>Potter-Elvehjem Tissue Grinder withPTFEPestle</td><td>Krackeler Scientific, Inc.</td><td>1-7725T-5</td><td></td></tr><tr><td>Eppendorf Centrifuge 5424 </td><td>Eppendorf</td><td>5424 000.410</td><td></td></tr><tr><td>4639 Cell Disruption Vessel</td><td>Parr Instrument Company</td><td>4639</td><td></td></tr><tr><td>Ficoll</td><td>Sigma-Aldrich</td><td>F5415</td><td></td></tr><tr><td>Polycarbonate centrifuge tubes</td><td>Beckman Coulter</td><td>P20314</td><td></td></tr><tr><td>SW-50.1 rotor </td><td>Beckman Coulter</td><td></td><td></td></tr><tr><td>L8-70M Ultracentrifuge</td><td>Beckman Coulter</td><td></td><td></td></tr><tr><td>Digitonin</td><td>Sigma-Aldrich</td><td>D5628</td><td></td></tr><tr><td>Lubrol PX (C12E9) </td><td>Calbiochem</td><td>205534</td><td></td></tr><tr><td>Axopatch 200B </td><td>Axon Instruments</td><td></td><td></td></tr><tr><td>Digidata 1440A </td><td>Molecular Device</td><td></td><td></td></tr><tr><td>pClamp10.0</td><td>Molecular Device</td><td></td><td></td></tr><tr><td>Manipulator</td><td>Sutter Instrument</td><td></td><td></td></tr><tr><td>Borosilicate glass capillary</td><td>World Precision Instruments</td><td>1308325</td><td></td></tr><tr><td>Flaming/Brown Micropipette Puller Model P-87</td><td>Sutter Instrument</td><td></td><td></td></tr></tbody></table>

f1fo atpase vesicle preparation and technique for performing patch clamp recordings of submitochondrial vesicle membranes

ミトコンドリア代謝、生存1、開発および、カルシウムシグナリング2を含む多くの重要な細胞機能に関与している。最も重要なミトコンドリア機能の二つはATP、酸化的リン酸化による細胞のエネルギー通貨、およびプログラムされた細胞死3つの信号の調停を効率よく製造に関連している。 ATPの生産を主に担当する酵素はまた、ATP合成酵素と呼ばれる4-5 F1FO-ATP合成酵素である。近年では、アポトーシスおよび壊死細胞死におけるミトコンドリアの役割は、かなりの注目を集めている。アポトーシス細胞死では、このようなBaxのようなBCL-2ファミリータンパク質は、ミトコンドリア外膜を入力してオリゴマー化し、サイトゾル6にプロアポトーシス因子を放出し、外膜を透過性。古典的な壊死性細胞死で、このような神経細胞における虚血や興奮毒性、ラーグによって生成されるようにeは、マトリックスカルシウムに難規制増加は、内膜の細孔の開口部、ミトコンドリア透過性遷移孔またはMPTPに貢献しています。これは、内膜を脱分極と外膜の破裂、プロアポトーシス因子の放出、代謝機能不全に貢献する、浸透シフトを引き起こす。のBcl-xLの7を含む多くのタンパク質は、その機能を調節する、F1FO ATP合成酵素と相互作用する。 BCL-XLはF1FO ATP合成酵素のβサブユニットと直接相互作用し、この相互作用はF1FO ATPase活性8中F1FOによってH +の正味の輸送を増加させる、F1FOATPasecomplex内に漏れコンダクタンスを減少させ、それによってミトコンドリアの効率を高める。 ATP合成酵素の活性及び変調を研究するために、我々はF1FO ATPアーゼを含む齧歯類の脳亜ミトコンドリアの小胞（SMVs）から分離された。 Alavian らに示されているようにSMVsはF1FO ATPアーゼの構造および機能の完全性を維持する。ここでは、方法が記載さ我々は、ラット脳からSMVsを単離するために正常に使用していると我々はSMVsのチャネル活性を分析するためのパッチクランプ法（イオンリークコンダクタンス）を描くこと。

我々のプロトコルの最初のステップは、 図1のウェスタンブロットにより示されるようにミトコンドリアの単離精製を可能にする。 図2に脳由来亜ミトコンドリアのベシクルパッチ記録の一例を示している。インサイドアウトパッチ構成を用いて、我々は、ATPによって変調されたチャネルの活性を示す。コントロール（CTL）記録（左）は平均で600 psのピークコンダク?...

Watch this Scientific Journal Video about F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes at JoVE.com

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

ラット脳からF1FO ATP合成酵素複合体に富む亜ミトコンドリアの小胞を単離する方法が記載されている。これらの小胞はパッチクランプ記録の技術を使用してF1FO ATPアーゼ複合体の活性の研究とその変調を可能にする。

<sub&gt; 1</sub&gt; F<sub&gt; O</sub亜ミトコンドリアの小胞膜のパッチクランプ記録を実行するための&gt; ATPアーゼ小胞の準備とテクニック

Mitochondria are involved in many important cellular  functions including metabolism, survival1, development and, calcium signaling2. Two of the most ...

f1fo-atpase-vesicle-preparation-technique-for-performing-patch-clamp

Universidad de Cartagena UDEC

Research

JoVE Journal

Neuroscience

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

10.2K ビュー.  Yale University. ラット脳からF1FO ATP合成酵素複合体に富む亜ミトコンドリアの小胞を単離する方法が記載されている。これらの小胞はパッチクランプ記録の技術を使用してF1FO ATPアーゼ複合体の活性の研究とその変調を可能にする。

ビデオ: F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

Detergent-free Ultrafast Reconstitution of Membrane Proteins into Lipid Bilayers Using Fusogenic Complementary-charged Proteoliposomes.

Detergents are indispensable for delivery of membrane proteins into 30-100 nm small unilamellar vesicles, while more complex, larger model lipid bilayers are less compatible with detergents.
Here we describe a strategy for bypassing this fundamental limitation using fusogenic oppositely charged liposomes bearing a membrane protein of interest. Fusion between such vesicles occurs within 5 min in a low ionic strength buffer. Positively charged fusogenic liposomes can be used as simple shuttle vectors for detergent-free delivery of membrane proteins into biomimetic target lipid bilayers, which are negatively charged. We also show how to reconstitute membrane proteins into fusogenic proteoliposomes with a fast 30-min protocol.
Combining these two approaches, we demonstrate a fast assembly of an electron transport chain consisting of two membrane proteins from E. coli, a primary proton pump bo3-oxidase and F1Fo ATP synthase, in membranes of vesicles of various sizes, ranging from 0.1 to &#62;10 microns, as well as ATP production by this chain.

Here we present two ultrafast protocols for reconstitution of membrane proteins into fusogenic proteoliposomes, and fusion of such proteoliposomes with target lipid bilayers for detergent-free delivery of these membrane proteins into the postfusion bilayer. The combination of these approaches enables fast and easily controlled assembly of complex multi-component membrane systems.

洗剤無料補完充電プロテオリポソーム融合ペプチドを用いた脂質膜に膜タンパク質の超高速再構成。

Detergents are indispensable for delivery of membrane proteins into 30-100 nm small unilamellar vesicles, while more complex, larger model lipid bilayers ...

生化学

Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei

F1-ATPase is a membrane-extrinsic catalytic subcomplex of F-type ATP synthase, an enzyme that uses the proton motive force across biological membranes to produce adenosine triphosphate (ATP). The isolation of the intact F1-ATPase from its native source is an essential prerequisite to characterize the enzyme&#39;s protein composition, kinetic parameters, and sensitivity to inhibitors. A highly pure and homogeneous F1-ATPase can be used for structural studies, which provide insight into molecular mechanisms of ATP synthesis and hydrolysis. This article describes a procedure for the purification of the F1-ATPase from Trypanosoma brucei, the causative agent of African trypanosomiases. The F1-ATPase is isolated from mitochondrial vesicles, which are obtained by hypotonic lysis from in vitro cultured trypanosomes. The vesicles are mechanically fragmented by sonication and the F1-ATPase is released from the inner mitochondrial membrane by the chloroform extraction. The enzymatic complex is further purified by consecutive anion exchange and size-exclusion chromatography. Sensitive mass spectrometry techniques showed that the purified complex is devoid of virtually any protein contaminants and, therefore, represents suitable material for structure determination by X-ray crystallography or cryo-electron microscopy. The isolated F1-ATPase exhibits ATP hydrolytic activity, which can be inhibited fully by sodium azide, a potent inhibitor of F-type ATP synthases. The purified complex remains stable and active for at least three days at room temperature. Precipitation by ammonium sulfate is used for long-term storage. Similar procedures have been used for the purification of F1-ATPases from mammalian and plant tissues, yeasts, or bacteria. Thus, the presented protocol can serve as a guideline for the F1-ATPase isolation from other organisms.

Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei

This protocol describes the purification of F1-ATPase from the cultured insect stage of Trypanosoma brucei. The procedure yields a highly pure, homogeneous, and active complex suitable for structural and enzymatic studies.

F1の分離-寄生原生トリパノソーマから atp アーゼ

F1-ATPase is a membrane-extrinsic catalytic subcomplex of F-type ATP synthase, an enzyme that uses the proton motive force across biological membranes to ...

Membrane Remodeling of Giant Vesicles in Response to Localized Calcium Ion Gradients

In a wide variety of fundamental cell processes, such as membrane trafficking and apoptosis, cell membrane shape transitions occur concurrently with local variations in calcium ion concentration. The main molecular components involved in these processes have been identified; however, the specific interplay between calcium ion gradients and the lipids within the cell membrane is far less known, mainly due to the complex nature of biological cells and the difficultly of observation schemes. To bridge this gap, a synthetic approach is successfully implemented to reveal the localized effect of calcium ions on cell membrane mimics. Establishing a mimic to resemble the conditions within a cell is a severalfold problem. First, an adequate biomimetic model with appropriate dimensions and membrane composition is required to capture the physical properties of cells. Second, a micromanipulation setup is needed to deliver a small amount of calcium ions to a particular membrane location. Finally, an observation scheme is required to detect and record the response of the lipid membrane to the external stimulation. This article offers a detailed biomimetic approach for studying the calcium ion-membrane interaction, where a lipid vesicle system, consisting of a giant unilamellar vesicle (GUV) connected to a multilamellar vesicle (MLV), is exposed to a localized calcium gradient formed using a microinjection system. The dynamics of the ionic influence on the membrane were observed using fluorescence microscopy and recorded at video frame rates. As a result of the membrane stimulation, highly curved membrane tubular protrusions (MTPs) formed inside the GUV, oriented away from the membrane. The described approach induces the remodeling of the lipid membrane and MTP production in an entirely contactless and controlled manner. This approach introduces a means to address the details of calcium ion-membrane interactions, providing new avenues to study the mechanisms of cell membrane reshaping.

We present a technique for contactless micromanipulation of vesicles, using localized calcium ion gradients. Microinjection of a calcium ion solution, in the vicinity of a giant lipid vesicle, is utilized to remodel the lipid membrane, resulting in the production of membrane tubular protrusions.

ローカライズされたカルシウム イオン勾配に対応した膜小胞の膜を改造

In a wide variety of fundamental cell processes, such as membrane trafficking and apoptosis, cell membrane shape transitions occur concurrently with local ...

化学

A Model Membrane Platform for Reconstituting Mitochondrial Membrane Dynamics

Mitochondrial dynamics is essential for the organelle&#8217;s diverse functions and cellular responses. The crowded, spatially complex, mitochondrial membrane is a challenging environment to distinguish regulatory factors. Experimental control of protein and lipid components can help answer specific questions of regulation. Yet, quantitative manipulation of these factors is challenging in cellular assays. To investigate the molecular mechanism of mitochondria inner-membrane fusion, we introduced an in vitro reconstitution platform that mimics the lipid environment of the mitochondrial inner-membrane. Here we describe detailed steps for preparing lipid bilayers and reconstituting mitochondrial membrane proteins. The platform allowed analysis of intermediates in mitochondrial inner-membrane fusion, and the kinetics for individual transitions, in a quantitative manner. This protocol describes the fabrication of bilayers with asymmetric lipid composition and describes general considerations for reconstituting transmembrane proteins into a cushioned bilayer. The method may be applied to study other membrane systems.

Mitochondrial fusion is an important homeostatic reaction underlying mitochondrial dynamics. Described here is an in vitro reconstitution system to study mitochondrial inner-membrane fusion that can resolve membrane tethering, docking, hemifusion, and pore opening. The versatility of this approach in exploring cell membrane systems is discussed.

ミトコンドリア膜動態を再構成するためのモデル膜プラットフォーム

Mitochondrial dynamics is essential for the organelle&#8217;s diverse functions and cellular responses. The crowded, spatially complex, mitochondrial ...

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae

Despite recent advances in the characterization of yeast mitochondrial proteome, the submitochondrial localization of a significant number of proteins remains elusive. Here, we describe a robust and effective method for determining the suborganellar localization of yeast mitochondrial proteins, which is considered a fundamental step during mitochondrial protein function elucidation. This method involves an initial step that consists of obtaining highly pure intact mitochondria. These mitochondrial preparations are then subjected to a subfractionation protocol consisting of hypotonic shock (swelling) and incubation with proteinase K (protease). During swelling, the outer mitochondrial membrane is selectively disrupted, allowing the proteinase K to digest proteins of the intermembrane space compartment. In parallel, to obtain information about the topology of membrane proteins, the mitochondrial preparations are initially sonicated, and then subjected to alkaline extraction with sodium carbonate. Finally, after centrifugation, the pellet and supernatant fractions from these different treatments are analyzed by SDS-PAGE and western blot. The submitochondrial localization as well as the membrane topology of the protein of interest is obtained by comparing its western blot profile with known standards.

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae

Despite recent advances, many yeast mitochondrial proteins still remain with their functions completely unknown. This protocol provides a simple and reliable method to determine the submitochondrial localization of proteins, which has been fundamental for the elucidation of their molecular functions.

出芽酵母サッカロミセスセレビシエにおけるサブソキアドタンパク質の局在化の評価

Despite recent advances in the characterization of yeast mitochondrial proteome, the submitochondrial localization of a significant number of proteins ...

ミトコンドリア接触部位の分離

An Improved Method to Isolate Mitochondrial Contact Sites

Mitochondria are present in virtually all eukaryotic cells and perform essential functions that go far beyond energy production, for instance, the synthesis of iron-sulfur clusters, lipids, or proteins, Ca2+ buffering, and the induction of apoptosis. Likewise, mitochondrial dysfunction results in severe human diseases such as cancer, diabetes, and neurodegeneration. In order to perform these functions, mitochondria have to communicate with the rest of the cell across their envelope, which consists of two membranes. Therefore, these two membranes have to interact constantly. Proteinaceous contact sites between the mitochondrial inner and outer membranes are essential in this respect. So far, several contact sites have been identified. In the method described here, Saccharomyces cerevisiae mitochondria are used to isolate contact sites and, thus, identify candidates that qualify for contact site proteins. We used this method to identify the mitochondrial contact site and cristae organizing system (MICOS) complex, one of the major contact site-forming complexes in the mitochondrial inner membrane, which is conserved from yeast to humans. Recently, we further improved this method to identify a novel contact site consisting of Cqd1 and the Por1-Om14 complex.

著者スポットライト:ミトコンドリアの接触部位と建築的洞察の発表 

Mitochondrial contact sites are protein complexes that interact with mitochondrial inner and outer membrane proteins. These sites are essential for the communication between the mitochondrial membranes and, thus, between the cytosol and the mitochondrial matrix. Here, we describe a method to identify candidates qualifying for this specific class of proteins.

ミトコンドリア接触部位を単離するための改良された方法

Mitochondria are present in virtually all eukaryotic cells and perform essential functions that go far beyond energy production, for instance, the ...

Preparation, Purification, and Use of Fatty Acid-containing Liposomes

Liposomes containing single-chain amphiphiles, particularly fatty acids, exhibit distinct properties compared to those containing diacylphospholipids due to the unique chemical properties of these amphiphiles. In particular, fatty acid liposomes enhance dynamic character, due to the relatively high solubility of single-chain amphiphiles. Similarly, liposomes containing free fatty acids are more sensitive to salt and divalent cations, due to the strong interactions between the carboxylic acid head groups and metal ions. Here we illustrate techniques for preparation, purification, and use of liposomes comprised in part or whole of single chain amphiphiles (e.g., oleic acids).

Liposomes containing single-chain amphiphiles, particularly fatty acids, exhibit distinct properties compared to those containing diacylphospholipids due to the unique chemical properties of single chain amphiphiles. Here we describe techniques for the preparation, purification, and use of liposomes comprised in part or whole of these amphiphiles.

準備、精製、および脂肪酸含有リポソームを用いる

Liposomes containing single-chain amphiphiles, particularly fatty acids, exhibit distinct properties compared to those containing diacylphospholipids due ...

生物工学

Reconstitution of a Kv Channel into Lipid Membranes for Structural and Functional Studies

To study the lipid-protein interaction in a reductionistic fashion, it is necessary to incorporate the membrane proteins into membranes of well-defined lipid composition. We are studying the lipid-dependent gating effects in a prototype voltage-gated potassium (Kv) channel, and have worked out detailed procedures to reconstitute the channels into different membrane systems. Our reconstitution procedures take consideration of both detergent-induced fusion of vesicles and the fusion of protein/detergent micelles with the lipid/detergent mixed micelles as well as the importance of reaching an equilibrium distribution of lipids among the protein/detergent/lipid and the detergent/lipid mixed micelles. Our data suggested that the insertion of the channels in the lipid vesicles is relatively random in orientations, and the reconstitution efficiency is so high that no detectable protein aggregates were seen in fractionation experiments. We have utilized the reconstituted channels to determine the conformational states of the channels in different lipids, record electrical activities of a small number of channels incorporated in planar lipid bilayers, screen for conformation-specific ligands from a phage-displayed peptide library, and support the growth of 2D crystals of the channels in membranes. The reconstitution procedures described here may be adapted for studying other membrane proteins in lipid bilayers, especially for the investigation of the lipid effects on the eukaryotic voltage-gated ion channels.

Procedures for complete reconstitution of a prototype voltage-gated potassium channel into lipid membranes are described. The reconstituted channels are suitable for biochemical assays, electrical recordings, ligand screening and electron crystallographic studies. These methods may have general applications to the structural and functional studies of other membrane proteins.

構造と機能研究のための脂質膜へのKvチャネルの再構築

To study the lipid-protein interaction in a reductionistic fashion, it is necessary to incorporate the membrane proteins into membranes of well-defined ...

要約

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この動画の章

洗剤無料補完充電プロテオリポソーム融合ペプチドを用いた脂質膜に膜タンパク質の超高速再構成。

F₁の分離-寄生原生トリパノソーマから atp アーゼ

ローカライズされたカルシウムイオン勾配に対応した膜小胞の膜を改造

ミトコンドリア膜動態を再構成するためのモデル膜プラットフォーム

出芽酵母サッカロミセスセレビシエにおけるサブソキアドタンパク質の局在化の評価

ミトコンドリア接触部位を単離するための改良された方法

ミトコンドリア接触部位を単離するための改良された方法

ミトコンドリア接触部位を単離するための改良された方法

準備、精製、および脂肪酸含有リポソームを用いる

構造と機能研究のための脂質膜へのKvチャネルの再構築

要約

さらに動画を探す

この動画の章

洗剤無料補完充電プロテオリポソーム融合ペプチドを用いた脂質膜に膜タンパク質の超高速再構成。

F1の分離-寄生原生トリパノソーマから atp アーゼ

ローカライズされたカルシウム イオン勾配に対応した膜小胞の膜を改造

ミトコンドリア膜動態を再構成するためのモデル膜プラットフォーム

出芽酵母サッカロミセスセレビシエにおけるサブソキアドタンパク質の局在化の評価

ミトコンドリア接触部位を単離するための改良された方法

ミトコンドリア接触部位を単離するための改良された方法

ミトコンドリア接触部位を単離するための改良された方法

準備、精製、および脂肪酸含有リポソームを用いる

構造と機能研究のための脂質膜へのKvチャネルの再構築

F₁の分離-寄生原生トリパノソーマから atp アーゼ

ローカライズされたカルシウムイオン勾配に対応した膜小胞の膜を改造