Here, we present a modification of a previously reported method that allows for the isolation of high quality and purified mitochondria from smaller quantities of mouse skeletal muscle. This procedure results in highly coupled mitochondria that respire with high function during microplate based respirometirc assays.
機能不全骨格筋ミトコンドリアは、加齢、肥満およびII型糖尿病で観察し、変化した代謝の役割を果たしています。分離されたミトコンドリア調製物からのミトコンドリア呼吸アッセイは、薬物や代謝を調節するタンパク質の作用メカニズム(複数可)のミトコンドリア機能の評価だけでなく、決意を可能にします。現在の単離方法は、多くの場合、呼吸アッセイに必要な高品質のミトコンドリアを得るために組織を大量に必要とします。本明細書に提示される方法は、(〜450μgの)は、高スループットの呼吸測定に使用するために、マウスの骨格筋の最小量(〜75-100ミリグラム)から単離することができる方法を高品質精製ミトコンドリア説明します。私たちは、分離法は、分光光度法、クエン酸合成酵素活性を測定することにより、92.5±2.0%、完全なミトコンドリアをもたらすことを決定しました。また、単離ミトコンドリアにおけるウェスタンブロット分析は、cytosoのかすかな発現をもたらしましたLICタンパク質、GAPDH、およびミトコンドリアタンパク質、COXIVの強い発現。単離されたミトコンドリアにおいて顕著GAPDHのバンドが存在しないことは、単離手順の間の非ミトコンドリア源からの少量の汚染の指標です。最も重要なのは、O 2消費率の測定マイクロプレートベースの技術とし、結合された呼吸アッセイのための呼吸調節比(RCR)を決定するには、高度(RCRを、全てのアッセイのための> 6)に接続ショーや機能ミトコンドリア。結論として、独立したミンチ工程の追加とはかなり以前に報告された方法のモーター駆動均質化速度を低下させることにより、高機能と呼吸性の高い結合されたミトコンドリアになり、マウス骨格筋の少ない量から高品質、精製されたミトコンドリアの単離を可能にしましたマイクロプレートベースrespirometircアッセイ中に。
The primary function of mitochondria is to produce ATP from oxidative phosphorylation. However, mitochondria have many other important cellular functions including but not limited to: the production and detoxification of reactive oxygen species, the regulation of cytoplasmic and mitochondrial calcium, organelle trafficking, ionic homeostasis, and involvement in apoptosis1,2. Therefore, it is not surprising that dysfunctional mitochondria play a role in many disease pathologies, such as aging, neurodegenerative diseases, cardiovascular disease, cancer, obesity, and diabetes3,4. Importantly, skeletal muscle mitochondria specifically are involved in many of these pathologies3-5.
Mitochondrial respiration assays using isolated mitochondria allow for the assessment of electron transport chain and oxidative phosphorylation function, and the determination of mechanism(s) of action of drugs and proteins that modulate metabolism. Mitochondrial isolation procedures exist for multiple tissue and cell types for a variety of species6,7. However, these procedures often require large quantities of tissue/cells for a high quality mitochondria yield necessary for classic respirometric assays.
Microplate based respirometirc assays allow for high throughput measurements using minimal quantities of isolated mitochondria, often just several µg per well8. Therefore, we present a modification of previously published methods7 to allow for high quality mitochondria to be isolated from smaller quantities of mouse skeletal muscle for use in microplate based respirometirc assays. In addition, methods are provided to establish the quality of the mitochondrial isolation preparation and the integrity of the mitochondrial membranes. Given that skeletal muscle mitochondria are involved in many pathological conditions, the measurement of O2 consumption in mechanistically driven studies is becoming more prevalent in biomedical research9,10.
本明細書に提示する方法は、マウス骨格筋の最小量(〜75〜100ミリグラム)から、ミトコンドリアの単離手順の詳細な説明を提供します。この単離手順は、O 2消費率、RCR値、最大のクエン酸シンターゼ活性およびイムノブロットからのタンパク質の発現によって証明されるように、高機能、純粋なミトコンドリア(〜450μgの)を生成することができます。重要なことには、この手順か…
The authors have nothing to disclose.
The Fralin Life Science Research Institute and The Metabolic Phenotyping Core at Virginia Tech supported this work.
Essentially Fatty | Sigma Aldrich | A6003 | N/A |
Acid Free- BSA | |||
Tris/HCl | Promega | H5123 | N/A |
KCL | Sigma Aldrich | P9541 | N/A |
Tris Base | Promega | H5135 | N/A |
EDTA | Sigma Aldrich | E6511 | N/A |
EGTA | Sigma Aldrich | E4378 | N/A |
Sucrose | Sigma Aldrich | S7903 | N/A |
D-Mannitol | Sigma Aldrich | 63559 | N/A |
Trypsin-EDTA (0.25%), phenol red | Thermo Scientific | 25200-056 | N/A |
Sodium Chloride White Crystals or Crystalline Powder ≥99.0 % |
Fisher Scientific | BP3581 | N/A |
Sodium dodecyl sulfate | Sigma Aldrich | L3771 | N/A |
Sodium deoxycholate | Sigma Aldrich | D6750 | N/A |
Polyoxyethylene (12) nonylphenyl ether, branched | Sigma Aldrich | 238651 | N/A |
Single Edge Razor Blades | Fisher Scientific | 12-640 | N/A |
Falcon- 100 uM Nylon Cell Strainers | Fisher Scientific | 352360 | N/A |
Halt Protease & Phosphatse Inhibitor Cocktail | Thermo Scientific | 1861284 | N/A |
1.5mL microcentrifuge tubes with screw cap | Thermo Scientific | 3474 | N/A |
Zirconium Oxide beads | Fisher Scientific | C9012112 | N/A |
GAPDH antibody (1D4) | Santa Cruz Biotechnology | sc-59540 | N/A |
Anti- COXIV antibody | Cell Signaling | 4844s | Any mitochondrial inner membrane protein will suffice |
Peroxidase conjugated affinipure Donkey, Anti Rabbit IgG (H+L) | Jackson ImmunoResearh | 711-035-152 | N/A |
Peroxidase conjugated affinipure Goat, Anti Mouse IgG (H+L) | Jackson ImmunoResearh | 115-001-003 | N/A |
Triton-X100 | Sigma Aldrich | X100 | N/A |
Pierce BCA Protein Assay Kit | Thermo Scientific | 23225 | N/A |
Pyruvic Acid, 98% | Sigma Aldrich | 107360 | Store at 4°C,pH to 7.4 with KOH prior to use in respirometric assay |
Succinic Acid | Sigma Aldrich | S9512 | Store at room temperature, pH to 7.4 with KOH prior to use in respirometric assay |
L(-) Malic Acid, BioXtra, ≥95% | Sigma Aldrich | M6413 | Store at room temperature, to 7.4 with KOH prior to use in respirometric assay |
L-Glutamic acid | Sigma Aldrich | G1251 | Store at room temperature, to 7.4 with KOH prior to use in respirometric assay, to 7.4 with KOH prior to use in respirometric assay |
Palmitoyl L-carnitine chloride | Sigma Aldrich | P1645 | Store at -20°C |
Oligomycin A, ≥ 95% (HPLC) | Sigma Aldrich | 75351 | Store at -20°C |
Carbonyl cyanide 4-(trifluoromethoxy) | Sigma Aldrich | C2920 | Store at 2-8°C |
phenylhydrazone | |||
≥98% (TLC), powder [FCCP] | |||
Antimycin A from streptomyces sp. | Sigma Aldrich | A8674 | Store at -20°C |
Adenosine 5′-diphosphate monopotassium salt dehydrate [ADP] | Sigma Aldrich | A5285 | Store at -20°C, to 7.4 with KOH prior to use in respirometric assay |
Rotenone | Sigma Aldrich | R8875 | Store at room temperature |