すべての動物に使用する手順は、ローカルの管理組織（Regierungspräsidiumカールスルーエ、カールスルーエ、ドイツ）が定める倫理指針に従った。 1。のsiRNA / PEI複合体の調製 以下のようなsiRNA / PEI複合体溶液を製造業者の指示を用いて調製される。 <ol><li>溶液A：端体積の四分の一までの無菌水を有するsiRNAの所望の量（必要な場合）で希釈し、端体積の半分まで10％グルコース溶液を上にして、さらにこれを希釈する。ボルテックス優しく上下にピペッティングにより混和する。 siRNAの最適量は、経験的に決定される必要があるが、動物あたり10μlの複合体溶液中の1μgのsiRNAは、最適化のための良い出発点である。 </li><li>溶液B：エンドボリュームの4分の1に滅菌水を上にして、PEI試薬の必要な量を希釈し、最終体積の半分、10％グルコース溶液を上にしてこれをさらに希釈する。渦GEntlyまたは上下にピペッティングにより混和する。 注意：PEI試薬の量は、トランスフェクションの効率に影響の複合体中のイオンバランスを決定します。同様に、PEI溶液の最適量は、経験的に決定されなければならない。私たちの手では、最適量は1μgのsiRNAのあたりのPEI溶液を0.12μLです。 </li><li>溶液Bと溶液Aを混合一斉に、穏やかにボルテックス。 </li><li>使用前にRTで15分間混合液をインキュベートする。この複合体は、4℃でRTで2時間および24時間安定である</li></ol> 2。髄膜注射<ol><li>それが正向反射の兆候を示していないまで、3％イソフルランでマウスを麻酔。加えて、さらなる麻酔の状態を確実にするために、テールおよび/または足のピンチレフをチェック。 </li><li>針挿入時に良好な視覚化を容易にするために、尾の付け根付近の動物の後方端部に毛皮の約2 cm 2とを剃る。 </li><li>マウスを所定の位置に手順の間に継​​続的なイソフルランの投与のためのノーズコーン、1.5％イソフルランを削減し、目の潤滑剤で、マウスの目をカバーしています。 </li><li>針に30のG 0.5に添付25μlのハミルトンシリンジを使用したsiRNAの混合溶液を使用する準備が準備します。 </li><li>最も顕著な1であること、静かにそれを押すことで、この領域を中心に、脊椎動物の列を修正する必要のある、L6の棘突起の位置を確認します。 </li><li>慎重にL5およびL6椎骨の溝との間に針を挿入し、このサインが硬膜内空間での針の成功エントリを示すのでテールフリックを観察。 ヒント：指の爪を使用して、1が同様に溝を見つけることができるはずです。 </li><li>テイルフリックが観察されたら、すぐに、しかし慎重に、一方の手で針位置を固定し、他方をゆっくりと物質の所望量を注入する。 ヒント：5〜10μlの間のボリュームがボリュームとして最適である5未満＆＃181、Lは信頼性が低く、10μLよりも大きなボリュームがあまりにも多くの圧力につながる。 </li><li>噴射が行われた後、麻酔から回復するためにケージに戻ってマウスを移動します。 </li><li>標的遺伝子の最適なダウンレギュレーションを達成するために、この注射を少なくとも2回以上24時間毎に繰り返します。 </li></ol>

<ol>
	<li>Hylden, J. L., Wilcox, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrathecal+morphine+in+mice:+a+new+technique.">Intrathecal morphine in mice: a new technique.</a> Eur. J. Pharmacol. 67, 313-316 (1980).</li><li>Stokes, J. A., Corr, M., Yaksh, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transient+tactile+allodynia+following+intrathecal+puncture+in+mouse:+contributions+of+Toll-like+receptor+signaling.">Transient tactile allodynia following intrathecal puncture in mouse: contributions of Toll-like receptor signaling.</a> Neurosci. Lett. 504, 215-218 (2011).</li><li>Goula, D., 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=Polyethylenimine-based+intravenous+delivery+of+transgenes+to+mouse+lung.">Polyethylenimine-based intravenous delivery of transgenes to mouse lung.</a> Gene Ther. , 1291-1295 (1998).</li><li>Fairbanks, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spinal+delivery+of+analgesics+in+experimental+models+of+pain+and+analgesia.">Spinal delivery of analgesics in experimental models of pain and analgesia.</a> Adv. Drug. Deliv. Rev. 55, 1007-1041 (2003).</li><li>Hohmann, A. G., Tsou, K., Walker, 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=Cannabinoid+modulation+of+wide+dynamic+range+neurons+in+the+lumbar+dorsal+horn+of+the+rat+by+spinally+administered+WIN55,212-2.">Cannabinoid modulation of wide dynamic range neurons in the lumbar dorsal horn of the rat by spinally administered WIN55,212-2.</a> Neurosci. Lett. 257, 119-122 (1998).</li><li>Song, Z. H., Takemori, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Involvement+of+spinal+kappa+opioid+receptors+in+the+antinociception+produced+by+intrathecally+administered+corticotropin-releasing+factor+in+mice.">Involvement of spinal kappa opioid receptors in the antinociception produced by intrathecally administered corticotropin-releasing factor in mice.</a> J. Pharmacol. Exp. Ther. 254, 363-368 (1990).</li><li>Trang, T., Sutak, M., Jhamandas, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Involvement+of+cannabinoid+(CB1)-receptors+in+the+development+and+maintenance+of+opioid+tolerance.">Involvement of cannabinoid (CB1)-receptors in the development and maintenance of opioid tolerance.</a> Neuroscience. , 1275-1288 (2007).</li><li>Yaksh, T. L., Rudy, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+catheterization+of+the+spinal+subarachnoid+space.">Chronic catheterization of the spinal subarachnoid space.</a> Physiol. Behav. 17, 1031-1036 (1976).</li><li>Tappe, A., 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=Synaptic+scaffolding+protein+Homer1a+protects+against+chronic+inflammatory+pain.">Synaptic scaffolding protein Homer1a protects against chronic inflammatory pain.</a> Nat. Med. , 677-681 (2006).</li><li>Bourinet, E., 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=Silencing+of+the+Cav3.2+T-type+calcium+channel+gene+in+sensory+neurons+demonstrates+its+major+role+in+nociception.">Silencing of the Cav3.2 T-type calcium channel gene in sensory neurons demonstrates its major role in nociception.</a> EMBO J. 24, 315-324 (2005).</li><li>Wang, X., 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=Gene+transfer+to+dorsal+root+ganglia+by+intrathecal+injection:+effects+on+regeneration+of+peripheral+nerves.">Gene transfer to dorsal root ganglia by intrathecal injection: effects on regeneration of peripheral nerves.</a> Mol. Ther. 12, 314-320 (2005).</li><li>Wigdor, S., Wilcox, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Central+and+systemic+morphine-induced+antinociception+in+mice:+contribution+of+descending+serotonergic+and+noradrenergic+pathways.">Central and systemic morphine-induced antinociception in mice: contribution of descending serotonergic and noradrenergic pathways.</a> J. Pharmacol. Exp. Ther. 242, 90-95 (1987).</li></ol>

著者らは、競合する経済的利益を宣言していません。

従って、髄腔内注射針の上記の技術は、有効な高速、特異的に局在し、かつ非破壊的である。技術的には、この手順の最も重要な側面は、溝に針の挿入のポイントです。それは、この手順は非常に穏やかに手と忍耐で行われていることが重要です。多くの外科的処置と同様に、トレーニングが成功した注入速度を向上させます。実際の実験中に、この手法は、直接注射が成功したか否かを確?...

脊髄は加工や痛みを伴う（侵害受容性）の入力4-7の送信を含む主要な生物学的プロセスおよび生理的機能の様々な非常に重要な中心地です。様々な実験技術は、髄腔内カテーテル8、脊髄マイクロインジェクション、および髄腔内注射針9の慢性的注入として、脊髄の薬理学的調節を容易にするために開発されてきた。それぞれの手法には独自の利点と欠点があり、実験パラダイムによっては一つの技術は、他よりも適しているかもしれません。髄内へのカテーテルの慢性的注入はラットにおいて容易に実現可能であるのに対して、この方法は、サイズの制限が指定され、マウスでは非常に困難である。成功率は非常に低く、運動障害は、しばしば、マウスにおいて厳しく限定さ硬膜下腔カテーテルのかさばる存在に起こる。また、薬の長期的な配信が頻繁な血液凝固にレ​​ンダリングされる慢性的に注入されたカテーテルの。最後に、免疫反応が一般的です。 これらの問題は、マウスの脊髄への薬物および試薬の迅速かつ解剖学的に制限されたアプリケーションを可能にしますpreimplantedカテーテルの非存在下で針を介して急性髄腔内注射の方法を使用して回避することができる。この方法は、完全に脊椎低減投与量および制限副作用を可能にする調節、ならびに物質がない送達する能力の特異性のような他の全身送達経路（ 例えば 、経口、静脈内、腹腔内等 ）上の髄腔内送達の利点を保持する髄腔内注射の間、針が硬膜と脊髄の間に挿入されているため、通常は血液脳関門を通過しない。しかしながら重要なことには、髄腔内送達の他の方法と比較して、髄腔内注射針注入法では、多数のアプリケーションを可能にする、最小侵襲性で任意のかなりの組織損傷を引き起こしたり、異物の移植による免疫反応を惹起せずに同じ動物。ただし、有効性を可能にするために、針の非​​常に正確な標的化のための技術的なスキルが必要です。 ここでは、視覚的に具体的に腰部脊髄を標的化するための最適な成功率を達成するための方法を示す。この実験で選択される注射部位は、脊髄脊椎を損傷する可能性を最小限にするために、終了に近いところ、L5およびL6脊椎動物列間の溝である。また、我々は、siRNAを用いた脊髄中の遺伝子をノックダウンするために、この技術の使用を示す。

<table border="0" cellpadding="0" cellspacing="0" width="1012">
	<colgroup>
		<col /> 
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:283px;">in vivo-jetPEI</td>
			<td style="width:255px;">Polyplus</td>
			<td style="width:288px;">201-10G</td>
			<td style="width:188px;"> </td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">WAVE1 siRNA</td>
			<td>Santa Cruz</td>
			<td>sc-36832</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Control siRNA-A</td>
			<td>Santa Cruz</td>
			<td>sc-37007</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Anti-&#223;-Tubulin III antibody</td>
			<td>Sigma</td>
			<td>T2200</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Anti-WAVE1 antibody</td>
			<td>R&#38;D Systems</td>
			<td>AF5514</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fast green dye</td>
			<td>Sigma</td>
			<td>F-7252</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Isoflurane</td>
			<td>Baxter</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Isoflurane setup</td>
			<td>Dr&#228;ger L&#252;beck</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Shaver</td>
			<td>Wella</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hamilton syringe Gastight 1702</td>
			<td>Hamilton</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">30G 1/2, 0,3 * 13mm Needle</td>
			<td>BD Microlance</td>
			<td>304000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Microscope Leica MS5</td>
			<td>Leica</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">WAVE1 forward primer for qRT-PCR</td>
			<td>Sigma</td>
			<td></td>
			<td>cacagagcctcaggacagg</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">WAVE1 reversed primer for qRT-PCR</td>
			<td>Sigma</td>
			<td></td>
			<td>cttttcaccaacggcatctt</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FastStart Essential DNA Green Master</td>
			<td>Roche</td>
			<td>6402712001</td>
			<td></td>
		</tr>
	</tbody>
</table>

in vivo sirna transfection and gene knockdown in spinal cord via rapid noninvasive lumbar intrathecal injections in mice

このレポートでは、カテーテル注入のすなわち独立した非侵襲的な方法で、急性くも膜下針注射技術に関するステップバイステップガイドを、説明しています。この手術法の技術的な制限は、手のフィネスにある。注射は、特に訓練された実験のために、迅速であり、この技術では、組織破壊が最小であるので、反復注射が可能であり、外来ツールにさらに免疫反応が起こらず、それによってより良く読み出すより具体的に与えること（ 例えばカテーテル）。脊髄変調の。物質の適用は、主として脊髄の標的領域に制限されるので、薬物は、大用量で適用する必要はなく、他の組織でのより重要なのは望ましくない効果は、全身送達で観察されるように、1を回避することができる2。また、我々はpolyethylenimの助けを借りて、核酸のin vivoトランスフェクションで、この手法を組み合わせるINE（PEI）の薬理学的薬剤の配信だけでなく、遺伝子、RNA、およびタンパク質モジュレーターを経由して 、脊椎の機能を研究するための多大な汎用性を提供し、試薬3、。

成功した注入を例証するために、我々は成体のC57Bl6マウス（8〜10週齢）にファストグリーンFCF染料を使用してこの手法を行った。動物は、染料が拡散し、次いでCO 2過剰投与により殺しするのに十分な時間を提供するために、注入後数分間回復させた。その後、脊椎動物の列には、解剖し脊髄を露出させた。拡散色素に対応する青色の斑点は、注射部位をマーク。脊髄への損傷の兆候?...

Watch this Scientific Journal Video about In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice at JoVE.com

In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice

このレポートでは、短い持続軽麻酔下マウスにおける腰椎脊髄におけるsiRNAのローカライズされたトランスフェクションのための髄腔内針穿刺の簡便かつ迅速な技術が記載されている。

マウスにおける急速な非侵襲腰椎髄腔内注射を経由して生体内 siRNAトランスフェクションと脊髄における遺伝子ノックダウン

This report describes a step-by-step guide to the technique of acute intrathecal needle injections in a noninvasive manner, i.e. independent of catheter ...

in-vivo-sirna-transfection-gene-knockdown-spinal-cord-via-rapid

Research

JoVE Journal

Biology

In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice

46.1K ビュー.  University of Heidelberg. このレポートでは、短い持続軽麻酔下マウスにおける腰椎脊髄におけるsiRNAのローカライズされたトランスフェクションのための髄腔内針穿刺の簡便かつ迅速な技術が記載されている。 

ビデオ: In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice

Noninvasive In Vivo Small Animal MRI and MRS: Basic Experimental Procedures

Small animal Magnetic Resonance (MR) research has emerged as an important element of modern biomedical research due to its non-invasive nature and the richness of biological information it provides. MR does not require any ionizing radiation and can noninvasively provide higher resolution and better signal-to-noise ratio in comparison to other tomographic or spectroscopic modalities. In this protocol, we will focus on small animal MR imaging and MR spectroscopy (MRI/MRS) to noninvasively acquire relaxation weighted 1H images of mouse and to obtain 31P spectra of mouse muscle. This work does not attempt to cover every aspect of small animal MRI/MRS but rather introduces basic procedures of mouse MRI/MRS experiments. The main goal of this work is to inform researchers of the basic procedures for in vivo MR experiments on small animals. The goal is to provide a better understanding of basic experimental procedures to allow researchers new to the MR field to better plan for non-MR components of their studies so that both MR and non-MR procedures are seamlessly integrated.

Noninvasive In Vivo Small Animal MRI and MRS: Basic Experimental Procedures

This work describes basic procedures of noninvasive small animal MRI and MRS in vivo.

非侵襲的インビボでの小動物MRIとMRS：基本的な実験手順

Small animal Magnetic Resonance (MR) research has emerged as an important element of modern biomedical research due to its non-invasive nature and the ...

生物学

Spinal Cord Electrophysiology

The neonatal mouse spinal cord is a model for studying the development of neural circuitries and locomotor movement. We demonstrate the spinal cord dissection and preparation of recording bath artificial cerebrospinal fluid used for locomotor studies. Once dissected, the spinal cord ventral nerve roots can be attached to a recording electrode to record the electrophysiologic signals of the central pattern generating circuitry within the lumbar cord.

A demonstration of the isolation of neonatal mouse spinal cord for electrophysiologic studies.

脊髄電気生理学

The neonatal mouse spinal cord is a model for studying the development of neural circuitries and locomotor movement. We demonstrate the spinal cord ...

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only to study the effects of downregulating single genes, but also to interrogate signaling pathways and other complex interaction networks.  These pathway analyses require both the use of relevant cellular models and methods that cause less perturbation to the cellular physiology.  Electroporation is increasingly being used as an effective way to introduce siRNA and other nucleic acids into difficult to transfect cell lines and primary cells without altering the signaling pathway under investigation. There are multiple critical steps to a successful siRNA experiment, and there are ways to simplify the work while improving the data quality at several experimental stages.  To help you get started with your siRNA mediated gene knockdown project, we will demonstrate how to perform a pathway study complete from collecting and counting the cells prior to electroporation through post transfection real-time PCR gene expression analysis.  The following study investigates the role of the transcriptional activator STAT6 in IL-4 dependent gene expression of CCL17 in a Burkitt lymphoma cell line (Namalwa).  The techniques demonstrated are useful for a wide range of siRNA-based experiments on both adherent and suspension cells.  We will also show how to streamline cell counting with the TC10 automated cell counter, how to electroporate multiple samples simultaneously using the MXcell electroporation system, and how to simultaneously assess RNA quality and quantity with the Experion automated electrophoresis system.

This procedure describes a quick and easy workflow to introduce siRNA into difficult to transfect cell lines and follow gene expression by real-time PCR. Use of an automated cell counter, multi-well electroporation plate, and automated electrophoresis station provide quick and reliable results without the need for expensive robotic handling.

ナマルバ細胞におけるIL - 4依存性遺伝子発現のsiRNAのノックダウン：遺伝子発現研究を簡素化する自動化セルカウンターの使い方

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only ...

RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes

This video protocol demonstrates an effective technique to knockdown a particular gene in an insect and conduct a novel bioassay to measure excretion rate. This method can be used to obtain a better understanding of the process of diuresis in insects and is especially useful in the study of diuresis in blood-feeding arthropods that are able to take up huge amounts of liquid in a single blood meal. 
This RNAi-mediated gene knockdown combined with an in vivo diuresis assay was developed by the Hansen lab to study the effects of RNAi-mediated knockdown of aquaporin genes on Aedes aegypti mosquito diuresis1. 
The protocol is setup in two parts: the first demonstration illustrates how to construct a simple mosquito injection device and how to prepare and inject dsRNA into the thorax of mosquitoes for RNAi-mediated gene knockdown. The second demonstration illustrates how to determine excretion rates in mosquitoes using an in vivo bioassay.

RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes

In this protocol we combine RNAi-mediated gene silencing with an in vivo diuresis assay to study the effects knockdown of genes of interest has on mosquito fluid excretion.

RNAiによる遺伝子ノックダウンと<emインビボで&gt;</em大人の女性の&gt;利尿アッセイ<em&gt;ネッタイシマカ</em&gt;蚊

This video protocol demonstrates an effective technique to knockdown a particular gene in an insect and conduct a novel bioassay to measure excretion ...

Isolation of Ribosome Bound Nascent Polypeptides in vitro to Identify Translational Pause Sites Along mRNA

The rate of translational elongation is non-uniform. mRNA secondary structure, codon usage and mRNA associated proteins may alter ribosome movement on the messagefor review see 1. However, it's now widely accepted that synonymous codon usage is the primary cause of non-uniform translational elongation rates1. Synonymous codons are not used with identical frequency. A bias exists in the use of synonymous codons with some codons used more frequently than others2. Codon bias is organism as well as tissue specific2,3. Moreover, frequency of codon usage is directly proportional to the concentrations of cognate tRNAs4. Thus, a frequently used codon will have higher multitude of corresponding tRNAs, which further implies that a frequent codon will be translated faster than an infrequent one. Thus, regions on mRNA enriched in rare codons (potential pause sites) will as a rule slow down ribosome movement on the message and cause accumulation of nascent peptides of the respective sizes5-8. These pause sites can have functional impact on the protein expression, mRNA stability and protein foldingfor review see 9. Indeed, it was shown that alleviation of such pause sites can alter ribosome movement on mRNA and subsequently may affect the efficiency of co-translational (in vivo) protein folding1,7,10,11. To understand the process of protein folding in vivo, in the cell, that is ultimately coupled to the process of protein synthesis it is essential to gain comprehensive insights into the impact of codon usage/tRNA content on the movement of ribosomes along mRNA during translational elongation.
Here we describe a simple technique that can be used to locate major translation pause sites for a given mRNA translated in various cell-free systems6-8. This procedure is based on isolation of nascent polypeptides accumulating on ribosomes during in vitro translation of a target mRNA. The rationale is that at low-frequency codons, the increase in the residence time of the ribosomes results in increased amounts of nascent peptides of the corresponding sizes. In vitro transcribed mRNA is used for in vitro translational reactions in the presence of radioactively labeled amino acids to allow the detection of the nascent chains. In order to isolate ribosome bound nascent polypeptide complexes the translation reaction is layered on top of 30% glycerol solution followed by centrifugation. Nascent polypeptides in polysomal pellet are further treated with ribonuclease A and resolved by SDS PAGE. This technique can be potentially used for any protein and allows analysis of ribosome movement along mRNA and the detection of the major pause sites. Additionally, this protocol can be adapted to study factors and conditions that can alter ribosome movement and thus potentially can also alter the function/conformation of the protein.

Isolation of Ribosome Bound Nascent Polypeptides in vitro to Identify Translational Pause Sites Along mRNA

A technique to identify translational pause sites on mRNA is described. This procedure is based on isolation of nascent polypeptides accumulating on ribosomes during in vitro translation of a target mRNA, followed by the size analysis of the nascent chains using a denaturing gel electrophoresis.

リボソーム結合した新生ポリペプチドの分離<em&gt; in vitroで</em&gt; mRNAに沿って並進一時サイトを識別するために

The rate of translational elongation is non-uniform. mRNA secondary structure, codon usage and mRNA associated proteins may alter ribosome movement on the ...

Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides

Extensive research has provided ample evidences suggesting that protein folding in the cell is a co-translational process1-5. However, the exact pathway that polypeptide chain follows during co-translational folding to achieve its functional form is still an enigma. In order to understand this process and to determine the exact conformation of the co-translational folding intermediates, it is essential to develop techniques that allow the isolation of RNCs carrying nascent chains of predetermined sizes to allow their further structural analysis.
SecM (secretion monitor) is a 170 amino acid E. coli protein that regulates expression of the downstream SecA (secretion driving) ATPase in the secM-secA operon6. Nakatogawa and Ito originally found that a 17 amino acid long sequence (150-FSTPVWISQAQGIRAGP-166) in the C-terminal region of the SecM protein is sufficient and necessary to cause stalling of SecM elongation at Gly165, thereby producing peptidyl-glycyl-tRNA stably bound to the ribosomal P-site7-9. More importantly, it was found that this 17 amino acid long sequence can be fused to the C-terminus of virtually any full-length and/or truncated protein thus allowing the production of RNCs carrying nascent chains of predetermined sizes7. Thus, when fused or inserted into the target protein, SecM stalling sequence produces arrest of the polypeptide chain elongation and generates stable RNCs both in vivo in E. coli cells and in vitro in a cell-free system. Sucrose gradient centrifugation is further utilized to isolate RNCs.
The isolated RNCs can be used to analyze structural and functional features of the co-translational folding intermediates. Recently, this technique has been successfully used to gain insights into the structure of several ribosome bound nascent chains10,11. Here we describe the isolation of bovine Gamma-B Crystallin RNCs fused to SecM and generated in an in vitro translation system.

We describe here a technique that is now routinely used to isolate stably bound ribosome nascent chain complexes (RNCs). This technique takes advantage of the discovery that a 17 amino acid long SecM "arrest sequence" can halt translation elongation in a prokaryotic (E. coli) system, when inserted into (or fused to the C-terminus) of virtually any protein.

リボソーム結合したポリペプチドを単離するためのツールと​​してSECM逮捕シーケンスを使用して、

Extensive research has provided ample evidences suggesting that protein folding in the cell is a co-translational process1-5. However, the exact pathway ...

Rapid Genetic Analysis of Epithelial-Mesenchymal Signaling During Hair Regeneration

Hair follicle morphogenesis, a complex process requiring interaction between epithelia-derived keratinocytes and the underlying mesenchyme, is an attractive model system to study organ development and tissue-specific signaling. Although hair follicle development is genetically tractable, fast and reproducible analysis of factors essential for this process remains a challenge. Here we describe a procedure to generate targeted overexpression or shRNA-mediated knockdown of factors using lentivirus in a tissue-specific manner. Using a modified version of a hair regeneration model 5, 6, 11, we can achieve robust gain- or loss-of-function analysis in primary mouse keratinocytes or dermal cells to facilitate study of epithelial-mesenchymal signaling pathways that lead to hair follicle morphogenesis. We describe how to isolate fresh primary mouse keratinocytes and dermal cells, which contain dermal papilla cells and their precursors, deliver lentivirus containing either shRNA or cDNA to one of the cell populations, and combine the cells to generate fully formed hair follicles on the backs of nude mice. This approach allows analysis of tissue-specific factors required to generate hair follicles within three weeks and provides a fast and convenient companion to existing genetic models.

Tissue-specific analysis of a hair follicle regeneration model using lentivirus to mediate gain- or loss-of-function.

髪の再生の間に上皮間葉シグナル伝達の迅速遺伝子解析

Hair follicle morphogenesis, a complex process requiring interaction between epithelia-derived keratinocytes and the underlying mesenchyme, is an ...

Intravenous Injections in Neonatal Mice

Intravenous injection is a clinically applicable manner to deliver therapeutics. For adult rodents and larger animals, intravenous injections are technically feasible and routine. However, some mouse models can have early onset of disease with a rapid progression that makes administration of potential therapies difficult. The temporal (or facial) vein is just anterior to the ear bud in mice and is clearly visible for the first two days after birth on either side of the head using a dissecting microscope. During this window, the temporal vein can be injected with volumes up to 50 &#956;l. The injection is safe and well tolerated by both the pups and the dams. A typical injection procedure is completed within 1-2 min, after which the pup is returned to the home cage. By the third postnatal day the vein is difficult to visualize and the injection procedure becomes technically unreliable. This technique has been used for delivery of adeno-associated virus (AAV) vectors, which in turn can provide almost body-wide, stable transgene expression for the life of the animal depending on the viral serotype chosen.

Animal models of pediatric disease can experience early onset and aggressive disease progression. Clinically relevant therapy delivery to young mouse models can be technically difficult. This protocol describes a non-invasive intravenous injection method for newborn mice within the first two postnatal days of life.

新生児マウスにおける静脈注射

Intravenous injection is a clinically applicable manner to deliver therapeutics. For adult rodents and larger animals, intravenous injections are ...

Filtration Isolation of Nucleic Acids:  A Simple and Rapid DNA Extraction Method

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad to extract cellular DNA from whole blood in less than 2 min. The blood specimen is treated with detergent, mixed briefly and applied by pipet to the separation membrane. The lysate wicks into the blotting pad due to capillary action, capturing the genomic DNA on the surface of the separation membrane. The extracted DNA is retained on the membrane during a simple wash step wherein PCR inhibitors are wicked into the absorbent blotting pad. The membrane containing the entrapped DNA is then added to the PCR reaction without further purification. This simple method does not require laboratory equipment and can be easily implemented with inexpensive laboratory supplies. Here we describe a protocol for highly sensitive detection and quantitation of HIV-1 proviral DNA from 100 &#181;l whole blood as a model for early infant diagnosis of HIV that could readily be adapted to other genetic targets.

We describe here a simple and rapid paper-based DNA extraction method of HIV proviral DNA from whole blood detected by quantitative PCR. This protocol can be extended for use in detecting other genetic markers or using alternative amplification methods.

核酸の濾過単離：簡易迅速DNA抽出方法

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad ...

Cystometric and External Urethral Sphincter Measurements in Awake Rats with Implanted Catheter and Electrodes Allowing for Repeated Measurements

Lower urinary tract function is mainly assessed by means of cystometric bladder function analysis in rodents. Conventional cystometries are usually performed as terminal analysis under urethane anesthesia. It is well known that anesthetic drugs can influence bladder function. Hence, the aim of this technique is to perform cystometric measurements of the urinary bladder and external urethral sphincter in lightly restrained awake rats. For this purpose, a bladder catheter is implanted into the bladder dome. Subsequently, two electrodes are implanted bilateral to the external urethral sphincter and a ground electrode is sutured to a non-responsive skeletal muscle. The bladder catheter and the three electrodes are finally tunneled subcutaneously to the neck region and affixed to a harness. With this technique, the lower urinary tract can be measured at multiple time points in the same animal to assess lower urinary tract function. The main application of this technique is the follow-up of simultaneous urinary bladder and external urethral sphincter function in awake healthy rats and after induction of a disease or injury. Moreover, subsequent lower urinary tract monitoring can be performed during evaluation of the disease/injury and to monitor treatment efficacy.

This protocol first describes the surgical procedure of the permanent implantation of a urinary bladder catheter combined with external urethral sphincter electrodes, and second, the measurement of the function of the urinary bladder and external urethral sphincter in implanted awake animals.

注入カテーテル電極の繰り返し測定を可能にすると目がさめているラットの膀胱内圧測定と外部尿道括約筋の測定

Lower urinary tract function is mainly assessed by means of cystometric bladder function analysis in rodents. Conventional cystometries are usually ...