我々は、ソフトウェア上のコメントにエミリージャクソン、ジョシュアZeidman、そしてニコラスレンに感謝します。この作品はGM95733（NM）に、BBBE 103316とMITスタートアップ資金（NMへ）によって賄われていた。

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J., Quinn, K., Zeidman, J., Maheshri, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-cycle+dependence+of+transcription+dominates+noise+in+gene+expression.">Cell-cycle dependence of transcription dominates noise in gene expression.</a> , (2013).</li><li>Kaufmann, B. B., Yang, Q., Mettetal, J. T., Van Oudenaarden, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heritable+stochastic+switching+revealed+by+single-cell+genealogy.">Heritable stochastic switching revealed by single-cell genealogy.</a> PLoS Biology. 5 (9), e239 (2007).</li><li>Cookson, S., Ostroff, N., Pang, W. L., Volfson, D., Hasty, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+dynamics+of+single-cell+gene+expression+over+multiple+cell+cycles.">Monitoring dynamics of single-cell gene expression over multiple cell cycles.</a> Molecular Systems Biology. 1 (1), 2005.0024 (2005).</li><li>Paliwal, S., Iglesias, P. A., Campbell, K., Hilioti, Z., Groisman, A., Levchenko, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MAPK-mediated+bimodal+gene+expression+and+adaptive+gradient+sensing+in+yeast.">MAPK-mediated bimodal gene expression and adaptive gradient sensing in yeast.</a> Nature. 446 (7131), 46-51 (2007).</li><li>Charvin, G., Cross, F. R., Siggia, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+microfluidic+device+for+temporally+controlled+gene+expression+and+long-term+fluorescent+imaging+in+unperturbed+dividing+yeast+cells.">A microfluidic device for temporally controlled gene expression and long-term fluorescent imaging in unperturbed dividing yeast cells.</a> PloS One. 3 (1), e1468 (2008).</li><li>Gordon, A., Colman-Lerner, A., Chin, T. E., Benjamin, K. R., Yu, R. C., Brent, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-cell+quantification+of+molecules+and+rates+using+open-source+microscope-based+cytometry.">Single-cell quantification of molecules and rates using open-source microscope-based cytometry.</a> Nat. Meth. 4 (2), 175-181 (2007).</li><li>Otsu, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Threshold+Selection+Method+from+Gray-Level+Histograms.">A Threshold Selection Method from Gray-Level Histograms.</a> IEEE Trans. Sys. Man. Cyber. 9 (1), 62-66 (1979).</li><li>Goranov, A. I., Cook, M., 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=The+rate+of+cell+growth+is+governed+by+cell+cycle+stage.">The rate of cell growth is governed by cell cycle stage.</a> Genes &amp; Development. 23 (12), 1408-1422 (2009).</li><li>To, T. -. L., Maheshri, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noise+Can+Induce+Bimodality+in+Positive+Transcriptional+Feedback+Loops+Without+Bistability.">Noise Can Induce Bimodality in Positive Transcriptional Feedback Loops Without Bistability.</a> Science. 327 (5969), 1142-1145 (2010).</li><li>O'Neill, E. M., Kaffman, A., Jolly, E. R., O'Shea, E. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+PHO4+nuclear+localization+by+the+PHO80-PHO85+cyclin-CDK+complex.">Regulation of PHO4 nuclear localization by the PHO80-PHO85 cyclin-CDK complex.</a> Science. 271 (5246), 209-212 (1996).</li><li>Raser, J. M., O'Shea, E. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+stochasticity+in+eukaryotic+gene+expression.">Control of stochasticity in eukaryotic gene expression.</a> Science. 304 (5678), 1811-1814 (2004).</li></ol>

著者は、彼らが競合する経済的利益を持っていないことを宣言します。

上記のプロトコルでは、マイクロ流体、またはソフトウェア開発の限られた経験を有する蛍光時系列データを取得して分析するための簡単​​な方法が記載されている。バーテン追跡および系統の割り当て;、関連するセルサイズおよび発現測定値を抽出し、それは1つは、単一の酵母細胞の経時蛍光ムービーを取得することができ、市販のマイクロ流体培養装置を用いて、時間と汎用性の高?...

遺伝子発現の単一細胞解析は遺伝子調節の多くの側面の我々の理解を進めたた。フローサイトメトリーまたは顕微鏡を用いて蛍光レポーター発現の静的なスナップショットは、単一セルの発現の分布に有用な情報を提供するが、直接遺伝子発現動態を通知するために必要な時系列データの履歴と進化を欠いている。蛍光タイムラプス顕微鏡は、単一セルの測定とその歴史の両方を取得する手段を提供します。種々の実験および解析技術は、このような遺伝子調節機能洞察を付与する、蛍光レポーター発現の映画を取得し、定量化するために開発されている（概説1を参照）は、セル間のばらつき2,3、細菌persister形成4、転写として開始と伸長5、6,7を破裂転写、細胞周期依存性8,9、および遺伝10。しかし、OBTaining品質単一細胞蛍光時系列は、培養の重要な技術的課題に制御環境で、取得した蛍光映画のハイスループット定量化における細胞の単層を伴う。ここでは、Sの蛍光ムービーを取得し、分析するための手順を説明細胞培養装置の製造における、またはソフトウェア開発の経験のない必須（ 図1） セレビシエ 。 まず、我々は詳細例プロトコルを一つ以上の蛍光レポーターを表現する出芽酵母用蛍光時系列ムービーを生成する。カスタマイズされたマイクロ流体文化室が建設され、成功した以前に11-13採用されてきたけれども、我々はCellAsic（ヘイワード、カリフォルニア州）から市販のマイクロ流体デバイスを使用しています。システム閉じ込める単分子層の成長への細胞とは、灌流環境の継続的な制御が可能になります。我々は提示顕微鏡プロトコルはfluorescを取得するための簡単​​な手段です。単一の酵母細胞の蛍光類似動画データを得レンス出芽酵母の映画が、任意の修飾実験プロトコルは、（カスタマイズ培養装置、代替メディア条件等 ）置換されていてもよい。 次に、時系列データを抽出するためにグラフィカルユーザーインターフェース（GUI）系蛍光時系列の迅速分析（移植片）のためのGUIと呼ばれるMATLABのソフトウェアパッケージ（Mathworks社、ナティック、MA）を使用して、映画の分析を概説単一細胞のために。移植片は、細胞をセグメント化し、追跡すると蛍光強度と幾何学的な情報を抽出することで汎用性の高い、オープンソースのソフトウェアパッケージセルID 14と同様の機能を備えています。しかし、移植片は重要な追加機能を提供します。まず、セ​​グメンテーションとデータの正確性ではなく、分析後の外れ値の領域のトレースだけ統計ゲーを確認するために追跡の結果を簡単にインタラクティブな編集を提供しています。また、分析にautomaticallに延びyは出芽酵母の関心系統および細胞周期の点を指定する。母と娘は、2つの独立したセル領域を形成するために分割したときに決定することは、セル全体（任意の接続つぼみ含む母）細胞周期8全体の測定値を決定する非常に重要です。スイートは、これらのタスクを達成するために3つのモジュールから構成されています。最初のセグメントはセル領域に焦点を当てたとやり場の明視野像との対比に基づいており、ユーザが定義し、視覚的にセグメントパラメータをテストすることができます。第二トラック（クロッカーら IDLルーチンのブレアとデュフレーヌのMATLAB実装を使用して、で入手可能：。 <a href="http://physics.georgetown.edu/matlab/" target="_blank">http://physics.georgetown.edu/MATLAB/</a> ）および時間を介して細胞領域を測定し、自動的に系統を割り当て、および目視検査を可能にする誤り訂正。シンプルなプロットのGUIは、クエリの単一セルのプロパティに含まれています。第三のモジュールは、つぼみ出現と分裂T​​Iを帰しMES、および全細胞時系列データならびにそれら第一及び第二の時間導関数を（9などを参照）を出力する。解析モジュールは、選択した統計ソフトウェアでその後の研究のためのスペース区切りのテキストフ​​ァイルとしてデータを出力します。したがって、パッケージは、ユーザがグラフィカル·インターフェースを介して高品質の時系列データを抽出することができます。我々は、細胞周期9の関数として単一出芽酵母細胞内でリアルタイムの転写率を推定するためにこの方法を使用している。モジュールは出芽酵母のために最適化されているが、パラメータや、必要に応じて、自由に利用可能なコードは、他の生物やイメージタイプに適合させることができる。セグメンテーション、トラッキング、系統割り当てアルゴリズムは、割り当てられたイメージングおよび問題の生物の種類に特異的であり得る。既存のアルゴリズムが置き換えられますが、それでもユーザーフレンドリーな目視検査とセグメンテーションの補正と常にoccuトラッキングエラーを可能にするGUIインタフェースを保持することができます任意のアルゴリズムでR。

<table border="1">
	<tbody>
		<tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Y04C Yeast Perfusion Plate</td>
			<td>CellAsic</td>
			<td>Y04C-02</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>ONIX Microfluidic Perfusion Platform</td>
			<td>CellAsic</td>
			<td>EV-262</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Axio Observer.Z1 Microscope</td>
			<td>Zeiss</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Plan-Apochromat 63X/1.40 Oil DIC objective</td>
			<td>Zeiss</td>
			<td>440762-9904-000</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cascade II EMCCD camera</td>
			<td>Photometrics</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Lumen 200 metal-halide arc lamp</td>
			<td>PRIOR Scientific</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Triple-bandpass dichroic filter cube and excitation and emission filter set</td>
			<td>Chroma Technology Corp</td>
			<td>set #89006</td>
			<td>Used for YFP (Venus/Citrine), CFP (Cerulean), RFP (mCherry/tdTomato)</td>
		</tr>
		<tr>
			<td>MAC 5000 controller and filter wheels</td>
			<td>Ludl Electronic Products</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>MATLAB R2011a</td>
			<td>Mathworks</td>
			<td>&nbsp;</td>
			<td>64-bit version handles large data files better than 32-bit</td>
		</tr>
	</tbody>
</table>

acquiring fluorescence time-lapse movies of budding yeast and analyzing single-cell dynamics using grafts

蛍光タイムラプス顕微鏡は、単一細胞レベルでの多くの生物学的過程の研究の強力なツールとなっています。具体的には、遺伝子発現の時間依存性を示すムービーは、その規制のダイナミクスへの洞察を提供するが、単一細胞の蛍光ムービーを取得し、分析する多くの技術的課題がある。ここでは、そのようなデータを生成するために市販のマイクロ流体培養装置を用いた単純なプロトコル、およびMATLABベースのグラフィカル·ユーザー·インターフェース（GUI）系蛍光画像を定量化するためのソフトウェアパッケージを説明する。ソフトウェアセグメントとトラックセル、ユー​​ザが視覚的にデータのエラーをキュレーションすることができますし、自動的に系統と分裂時間を割り当てます。 GUIはさらに、全細胞トレースならびにそれら第一及び第二の時間導関数を生成するために時系列を解析する。ソフトウェアはS.のために設計されましたが出芽酵母は、そのモジュール性と多様性は、それトン許可する必要がありますいくつかの変更を他の細胞型を研究するためのプラットフォームとしての役割を果たす、Ø。

正常に実行され、分析実験は、現実的に割り当てられた芽の出現と分割時間を持つ単一の細胞全体のために主に連続的な時系列が得られます。例として、我々は表4、Y47の成長とグローバルな表現は、単一の細胞で、経時的に変化するかを観察するために構成的ADH1プロモーターによって駆動セルリアン蛍光タンパク質（CFP）（の統合されたコピーを表現ハプロイド酵...

Watch this Scientific Journal Video about Acquiring Fluorescence Time-lapse Movies of Budding Yeast and Analyzing Single-cell Dynamics using GRAFTS at JoVE.com

Acquiring Fluorescence Time-lapse Movies of Budding Yeast and Analyzing Single-cell Dynamics using GRAFTS

我々は、単一セルの時系列データを抽出するために蛍光成長酵母細胞の顕微鏡ムービー、GUIベースのソフトウェアパッケージを取得する単純なプロトコルを提示する。分析では、目視検査と追跡対象データの手動キュレーションと統合され自動化された系統と分裂時間の割り当てが含まれています。

出芽酵母の蛍光タイムラプス作品を取得し、移植片を使用したシングルセルダイナミクスの解析

Fluorescence time-lapse microscopy has become a powerful tool in the study of many biological processes at the single-cell level. In particular, movies ...

acquiring-fluorescence-time-lapse-movies-budding-yeast-analyzing

Research

JoVE Journal

Biology

12.7K ビュー.  Massachusetts Institute of Technology. 我々は、単一セルの時系列データを抽出するために蛍光成長酵母細胞の顕微鏡ムービー、GUIベースのソフトウェアパッケージを取得する単純なプロトコルを提示する。分析では、目視検査と追跡対象データの手動キュレーションと統合され自動化された系統と分裂時間の割り当てが含まれています。

ビデオ: Acquiring Fluorescence Time-lapse Movies of Budding Yeast and Analyzing Single-cell Dynamics using GRAFTS

Measuring Replicative Life Span in the Budding Yeast

Aging is a degenerative process characterized by a progressive deterioration of cellular components and organelles resulting in mortality. The budding yeast Saccharomyces cerevisiae has been used extensively to study the biology of aging, and several determinants of yeast longevity have been shown to be conserved in multicellular eukaryotes, including worms, flies, and mice 1. Due to the lack of easily quantified age-associated phenotypes, aging in yeast has been assayed almost exclusively by measuring the life span of cells in different contexts, with two different life span paradigms in common usage 2. Chronological life span refers to the length of time that a mother cell can survive in a non-dividing, quiescence-like state, and is proposed to serve as a model for aging of post-mitotic cells in multicellular eukaryotes. Replicative life span, in contrast, refers the number of daughter cells produced by a mother cell prior to senescence, and is thought to provide a model of aging in mitotically active cells. Here we present a generalized protocol for measuring the replicative life span of budding yeast mother cells. The goal of the replicative life span assay is to determine how many times each mother cell buds. The mother and daughter cells can be easily differentiated by an experienced researcher using a standard light microscope (total magnification 160X), such as the Zeiss Axioscope 40 or another comparable model. Physical separation of daughter cells from mother cells is achieved using a manual micromanipulator equipped with a fiber-optic needle. Typical laboratory yeast strains produce 20-30 daughter cells per mother and one life span experiment requires 2-3 weeks.

In this article we present a general protocol for measuring the replicative life span of yeast mother cells.

出芽酵母の複製寿命の測定

Aging is a degenerative process characterized by a progressive deterioration of cellular components and organelles resulting in mortality. The budding ...

生物学

Time-lapse Imaging of Mitosis After siRNA Transfection

Changes in cellular organization and chromosome dynamics that occur during mitosis are tightly coordinated to ensure accurate inheritance of genomic and cellular content. Hallmark events of mitosis, such as chromosome movement, can be readily tracked on an individual cell basis using time-lapse fluorescence microscopy of mammalian cell lines expressing specific GFP-tagged proteins. In combination with RNAi-based depletion, this can be a powerful method for pinpointing the stage(s) of mitosis where defects occur after levels of a particular protein have been lowered. In this protocol, we present a basic method for assessing the effect of depleting a potential mitotic regulatory protein on the timing of mitosis. Cells are transfected with siRNA, placed in a stage-top incubation chamber, and imaged using an automated fluorescence microscope. We describe how to use software to set up a time-lapse experiment, how to process the image sequences to make either still-image montages or movies, and how to quantify and analyze the timing of mitotic stages using a cell-line expressing mCherry-tagged histone H2B. Finally, we discuss important considerations for designing a time-lapse experiment. This strategy is complementary to other approaches and offers the advantages of 1) sensitivity to changes in kinetics that might not be observed when looking at cells as a population and 2) analysis of mitosis without the need to synchronize the cell cycle using drug treatments. The visual information from such imaging experiments not only allows the sub-stages of mitosis to be assessed, but can also provide unexpected insight that would not be apparent from cell cycle analysis by FACS.

Here we describe a basic protocol to image and quantify the mitotic timing of live mammalian tissue culture cells after siRNA transfection.

siRNAトランスフェクション後の有糸分裂のタイムラプスイメージング

Changes in cellular organization and chromosome dynamics that occur during mitosis are tightly coordinated to ensure accurate inheritance of genomic and ...

Recording Multicellular Behavior in Myxococcus xanthus Biofilms using Time-lapse Microcinematography

A swarm of the &delta;-proteobacterium Myxococcus xanthus contains millions of cells that act as a collective, coordinating movement through a series of signals to create complex, dynamic patterns as a response to environmental cues. These patterns are self-organizing and emergent; they cannot be predicted by observing the behavior of the individual cells. Using a time-lapse microcinematography tracking assay, we identified a distinct emergent pattern in M. xanthus called chemotaxis, defined as the directed movement of a swarm up a nutrient gradient toward its source 1.
In order to efficiently characterize chemotaxis via time-lapse microcinematography, we developed a highly modifiable plate complex (Figure 1) and constructed a cluster of 8 microscopes (Figure 2), each capable of capturing time-lapse videos. The assay is rigorous enough to allow consistent replication of quantifiable data, and the resulting videos allow us to observe and track subtle changes in swarm behavior. Once captured, the videos are transferred to an analysis/storage computer with enough memory to process and store thousands of videos. The flexibility of this setup has proven useful to several members of the M. xanthus community.

Recording Multicellular Behavior in Myxococcus xanthus Biofilms using Time-lapse Microcinematography

To study Myxococcus xanthus swarm behavior, we have designed a time-lapse microcinematography protocol that can be modified for different assays. It employs standard growth conditions adapted for microscopy, and yields reproducible results by the use of inexpensive, reusable silicone gaskets. We have used this method to quantify multicellular chemotaxis.

で多細胞の動作を記録する Myxococcusザンザス</emタイムラプスMicrocinematographyを使用して>バイオフィルム

A swarm of the &delta;-proteobacterium Myxococcus xanthus contains millions of cells that act as a collective, coordinating movement through a series of ...

Quantitative Analysis of Random Migration of Cells Using Time-lapse Video Microscopy

Cell migration is a dynamic process, which is important for embryonic development, tissue repair, immune system function, and tumor invasion 1, 2. During directional migration, cells move rapidly in response to an extracellular chemotactic signal, or in response to intrinsic cues 3 provided by the basic motility machinery. Random migration occurs when a cell possesses low intrinsic directionality, allowing the cells to explore their local environment.
Cell migration is a complex process, in the initial response cell undergoes polarization and extends protrusions in the direction of migration 2. Traditional methods to measure migration such as the Boyden chamber migration assay is an easy method to measure chemotaxis in vitro, which allows measuring migration as an end point result. However, this approach neither allows measurement of individual migration parameters, nor does it allow to visualization of morphological changes that cell undergoes during migration.
Here, we present a method that allows us to monitor migrating cells in real time using video - time lapse microscopy. Since cell migration and invasion are hallmarks of cancer, this method will be applicable in studying cancer cell migration and invasion in vitro. Random migration of platelets has been considered as one of the parameters of platelet function 4, hence this method could also be helpful in studying platelet functions. This assay has the advantage of being rapid, reliable, reproducible, and does not require optimization of cell numbers. In order to maintain physiologically suitable conditions for cells, the microscope is equipped with CO2 supply and temperature thermostat. Cell movement is monitored by taking pictures using a camera fitted to the microscope at regular intervals. Cell migration can be calculated by measuring average speed and average displacement, which is calculated by Slidebook software.

This method allows monitoring of cells in real time and quantitative measurements of different cell migration parameters such as speed, displacement, and velocity. Unlike the traditional methods, this real time approach is not based on endpoint quantitative migration measurements; instead it allows monitoring and calculating different parameters continuously.

タイムラプスビデオ顕微鏡を用いた細胞のランダムな移行の定量分析

Cell migration is a dynamic process, which is important for embryonic development, tissue repair, immune system function, and tumor invasion 1, 2. During ...

Budding Yeast Protein Extraction and Purification for the Study of Function, Interactions, and Post-translational Modifications

Homogenization by bead beating is a fast and efficient way to release DNA, RNA, proteins, and metabolites from budding yeast cells, which are notoriously hard to disrupt. Here we describe the use of a bead mill homogenizer for the extraction of proteins into buffers optimized to maintain the functions, interactions and post-translational modifications of proteins. Logarithmically growing cells expressing the protein of interest are grown in a liquid growth media of choice. The growth media may be supplemented with reagents to induce protein expression from inducible promoters (e.g. galactose), synchronize cell cycle stage (e.g. nocodazole), or inhibit proteasome function (e.g. MG132). Cells are then pelleted and resuspended in a suitable buffer containing protease and/or phosphatase inhibitors and are either processed immediately or frozen in liquid nitrogen for later use. Homogenization is accomplished by six cycles of 20 sec&#160;bead-beating (5.5 m/sec), each followed by one minute incubation on ice. The resulting homogenate is cleared by centrifugation and small particulates can be removed by filtration. The resulting cleared whole cell extract (WCE) is precipitated using 20% TCA for direct analysis of total proteins by SDS-PAGE followed by Western blotting. Extracts are also suitable for affinity purification of specific proteins, the detection of post-translational modifications, or the analysis of co-purifying proteins. As is the case for most protein purification protocols, some enzymes and proteins may require unique conditions or buffer compositions for their purification and others may be unstable or insoluble under the conditions stated. In the latter case, the protocol presented may provide a useful starting point to empirically determine the best bead-beating strategy for protein extraction and purification. We show the extraction and purification of an epitope-tagged SUMO E3 ligase, Siz1, a cell cycle regulated protein that becomes both sumoylated and phosphorylated, as well as a SUMO-targeted ubiquitin ligase subunit, Slx5.

The preparation of high quality yeast cell extracts is a necessary first step in the analysis of individual proteins or entire proteomes. Here we describe a fast, efficient, and reliable homogenization protocol for budding yeast cells that has been optimized to preserve protein functions, interactions, and post-translational modifications.

機能の研究、相互作用、および翻訳後修飾のため出芽酵母タンパク質の抽出と精製

Homogenization by bead beating is a fast and efficient way to release DNA, RNA, proteins, and metabolites from budding yeast cells, which are notoriously ...

High-resolution Time-lapse Imaging and Automated Analysis of Microtubule Dynamics in Living Human Umbilical Vein Endothelial Cells

The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes within individual endothelial cells (ECs). These processes are critical for homeostatic maintenance such as wound healing, and are also crucial in promoting tumor growth and metastasis. EC morphology is defined by the organization of the cytoskeleton, a tightly regulated system of actin and microtubule (MT) dynamics that is known to control EC branching, polarity and directional migration, essential components of angiogenesis. To study MT dynamics, we used high-resolution fluorescence microscopy coupled with computational image analysis of fluorescently-labeled MT plus-ends to investigate MT growth dynamics and the regulation of EC branching morphology and directional migration. Time-lapse imaging of living Human Umbilical Vein Endothelial Cells (HUVECs) was performed following transfection with fluorescently-labeled MT End Binding protein 3 (EB3) and Mitotic Centromere Associated Kinesin (MCAK)-specific cDNA constructs to evaluate effects on MT dynamics. PlusTipTracker software was used to track EB3-labeled MT plus ends in order to measure MT growth speeds and MT growth lifetimes in time-lapse images. This methodology allows for the study of MT dynamics and the identification of how localized regulation of MT dynamics within sub-cellular regions contributes to the angiogenic processes of EC branching and migration.

Protocols for Human Umbilical Vein Endothelial Cell (HUVEC) culture, transient transfection of fluorescently-labeled markers of microtubule growth, live-cell imaging and automated analysis of interphase microtubule growth dynamics are detailed.

リビングヒト臍帯静脈内皮細胞における高解像度タイムラプスイメージングと微小管ダイナミクスの自動解析

The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes ...

Applications of pHluorin for Quantitative, Kinetic and High-throughput Analysis of Endocytosis in Budding Yeast

Green fluorescent protein (GFP) and its variants are widely used tools for studying protein localization and dynamics of events such as cytoskeletal remodeling and vesicular trafficking in living cells. Quantitative methodologies using chimeric GFP fusions have been developed for many applications; however, GFP is somewhat resistant to proteolysis, thus its fluorescence persists in the lysosome/vacuole, which can impede quantification of cargo trafficking in the endocytic pathway. An alternative method for quantifying endocytosis and post-endocytic trafficking events makes use of superecliptic pHluorin, a pH-sensitive variant of GFP that is quenched in acidic environments. Chimeric fusion of pHluorin to the cytoplasmic tail of transmembrane cargo proteins results in a dampening of fluorescence upon incorporation of the cargo into multivesicular bodies (MVBs) and delivery to the lysosome/vacuole lumen. Thus, quenching of vacuolar fluorescence facilitates quantification of endocytosis and early events in the endocytic pathway. This paper describes methods using pHluorin-tagged cargos for quantification of endocytosis via fluorescence microscopy, as well as population-based assays using flow cytometry.

Accurate quantification of vesicular trafficking events often provides key insights into roles for specific proteins and the effects of mutations. This paper presents methods for using superecliptic pHluorin, a pH-sensitive GFP variant, as a tool for quantification of endocytic events in living cells using quantitative fluorescence microscopy and flow cytometry.

出芽酵母におけるエンドサイトーシスの定量的、動力学的およびハイスループット分析のためのpHluorinの応用

Green fluorescent protein (GFP) and its variants are widely used tools for studying protein localization and dynamics of events such as cytoskeletal ...

Using Microfluidic Devices to Measure Lifespan and Cellular Phenotypes in Single Budding Yeast Cells

Budding yeast Saccharomyces cerevisiae is an important model organism in aging research. Genetic studies have revealed many genes with conserved effects on the lifespan across species. However, the molecular causes of aging and death remain elusive. To gain a systematic understanding of the molecular mechanisms underlying yeast aging, we need high-throughput methods to measure lifespan and to quantify various cellular and molecular phenotypes in single cells. Previously, we developed microfluidic devices to track budding yeast mother cells throughout their lifespan while flushing away newborn daughter cells. This article presents a method for preparing microfluidic chips and for setting up microfluidic experiments. Multiple channels can be used to simultaneously track cells under different conditions or from different yeast strains. A typical setup can track hundreds of cells per channel and allow for high-resolution microscope imaging throughout the lifespan of the cells. Our method also allows detailed characterization of the lifespan, molecular markers, cell morphology, and the cell cycle dynamics of single cells. In addition, our microfluidic device is able to trap a significant amount of fresh mother cells that can be identified by downstream image analysis, making it possible to measure the lifespan with higher accuracy.

This article presents a protocol optimized for the production of microfluidic chips and the setup of microfluidic experiments to measure the lifespan and cellular phenotypes of single yeast cells.

シングル出芽酵母細胞での寿命と細胞表現型を測定するためのマイクロ流体デバイスを使用しました

Budding yeast Saccharomyces cerevisiae is an important model organism in aging research. Genetic studies have revealed many genes with conserved effects ...

High-resolution Imaging and Analysis of Individual Astral Microtubule Dynamics in Budding Yeast

Dynamic microtubules are fundamental to many cellular processes, and accurate measurements of microtubule dynamics can provide insight into how cells regulate these processes and how genetic mutations impact regulation. The quantification of microtubule dynamics in metazoan models has a number of associated challenges, including a high microtubule density and limitations on genetic manipulations. In contrast, the budding yeast model offers advantages that overcome these challenges. This protocol describes a method to measure the dynamics of single microtubules in living yeast cells. Cells expressing fluorescently tagged tubulin are adhered to assembled slide chambers, allowing for stable time-lapse image acquisition. A detailed guide for high-speed, four-dimensional image acquisition is also provided, as well as a protocol for quantifying the properties of dynamic microtubules in confocal image stacks. This method, combined with conventional yeast genetics, provides an approach that is uniquely suited for quantitatively assessing the effects of microtubule regulators or mutations that alter the activity of tubulin subunits.

Budding yeast is an advantageous model for studying microtubule dynamics in vivo due to its powerful genetics and the simplicity of its microtubule cytoskeleton. The following protocol describes how to transform and culture yeast cells, acquire confocal microscopy images, and quantitatively analyze microtubule dynamics in living yeast cells.

出芽酵母における高解像度画像と個人アストラル微小管動態の解析

Dynamic microtubules are fundamental to many cellular processes, and accurate measurements of microtubule dynamics can provide insight into how cells ...

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy

Live-cell imaging is a microscopy technique used to examine cell and protein dynamics in living cells. This imaging method is not toxic, generally does not interfere with cell physiology, and requires minimal experimental handling. The low levels of technical interference enable researchers to study cells across multiple cycles of mitosis and to observe meiosis from beginning to end. Using fluorescent tags such as Green Fluorescent Protein (GFP) and Red Fluorescent Protein (RFP), researchers can analyze different factors whose functions are important for processes like transcription, DNA replication, cohesion, and segregation. Coupled with data analysis using Fiji (a free, optimized ImageJ version), live-cell imaging offers various ways of assessing protein movement, localization, stability, and timing, as well as nuclear dynamics and chromosome segregation. However, as is the case with other microscopy methods, live-cell imaging is limited by the intrinsic properties of light, which put a limit to the resolution power at high magnifications, and is also sensitive to photobleaching or phototoxicity at high wavelength frequencies. However, with some care, investigators can bypass these physical limitations by carefully choosing the right conditions, strains, and fluorescent markers to allow for the appropriate visualization of mitotic and meiotic events.

Here, we present live-cell imaging which is a non-toxic microscopy method that allows researchers to study protein behavior and nuclear dynamics in living fission yeast cells during mitosis and meiosis.

蛍光生細胞顕微鏡によるミトティック・マイオシス酵母核ダイナミクスの検討

Live-cell imaging is a microscopy technique used to examine cell and protein dynamics in living cells. This imaging method is not toxic, generally does ...