מחקר זה נתמך על ידי תכנית המחקר העירונית של NIH, המכון הלאומי למחקר דנטלי Craniofacial.

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taking+cell-matrix+adhesions+to+the+third+dimension.">Taking cell-matrix adhesions to the third dimension.</a> Science. 294, 1708-1712 (2001).</li><li>Weigert, R., Sramkova, M., Parente, L., Amornphimoltham, P., Masedunskas, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intravital+microscopy:+a+novel+tool+to+study+cell+biology+in+living+animals.">Intravital microscopy: a novel tool to study cell biology in living animals.</a> Histochem Cell Biol. 133, 481-491 (2010).</li><li>Dunn, K. W., 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=Functional+studies+of+the+kidney+of+living+animals+using+multicolor+two-photon+microscopy.">Functional studies of the kidney of living animals using multicolor two-photon microscopy.</a> Am. J. Physiol. Cell Physiol. 283, C905-C916 (2002).</li><li>Masedunskas, A., Porat-Shliom, N., Weigert, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulated+exocytosis:+novel+insights+from+intravital+microscopy.">Regulated exocytosis: novel insights from intravital microscopy.</a> Traffic. 13, 627-634 (2012).</li><li>Masedunskas, 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=Role+for+the+actomyosin+complex+in+regulated+exocytosis+revealed+by+intravital+microscopy.">Role for the actomyosin complex in regulated exocytosis revealed by intravital microscopy.</a> Proc. Natl. Acad. Sci. U.S.A. 108, 13552-13557 (2011).</li><li>Masedunskas, A., Weigert, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intravital+two-photon+microscopy+for+studying+the+uptake+and+trafficking+of+fluorescently+conjugated+molecules+in+live+rodents.">Intravital two-photon microscopy for studying the uptake and trafficking of fluorescently conjugated molecules in live rodents.</a> Traffic. 9, 1801-1810 (2008).</li><li>Sramkova, M., Masedunskas, A., Parente, L., Molinolo, A., Weigert, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+plasmid+DNA+in+the+salivary+gland+epithelium:+novel+approaches+to+study+dynamic+cellular+processes+in+live+animals.">Expression of plasmid DNA in the salivary gland epithelium: novel approaches to study dynamic cellular processes in live animals.</a> Am. J. Physiol. Cell Physiol. 297, C1347-C1357 (2009).</li><li>Sramkova, M., Najman, S., 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=.">.</a> Current Frontiers and Perspectives in Cell Biology. , (2012).</li><li>Masedunskas, 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=Everything+you+need+to+know+about+intravital+microscopy:+A+practical+guide+on+imaging+intracellular+structures+in+live+animals.">Everything you need to know about intravital microscopy: A practical guide on imaging intracellular structures in live animals.</a> Bioarchitecture. 2, (2012).</li><li>Masedunskas, A., Sramkova, M., Parente, L., Weigert, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intravital+microscopy+to+image+membrane+trafficking+in+live+rats.">Intravital microscopy to image membrane trafficking in live rats.</a> Methods Mol. 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עד כה מבני subcellular כבר צילמו בעיקר במבחנה (תרביות תאים כלומר) או in vivo (כלומר איבר תרבויות, פרוסות רקמה, הכנות acinar) מערכות מודל לשעבר שלעתים קרובות אינו לשחזר את המאפיינים של רקמות גרו בשלמותה 6. מבחינה זו, הגישה המוצגת כאן מייצגת פריצת דרך משמעות?...

בשני העשורים האחרונים כניסתו של מיקרוסקופיה חי והשימוש בחלבוני ניאון הובילו לפריצות דרך משמעותיות בכל תהליך סלולארי ניתן להעלות על הדעת, ובכך לקדם את ההבנה של ביולוגיה של תא 1 שלנו. תחום זה נהנה מאוד מהשימוש בתרביות תאים של יונקים שהן מערכות מודל חזקות מאוד, במיוחד כאשר מדובר במניפולציות ניסיוני. עם זאת, הם לא לעתים קרובים לספק ייצוג אמיתי של הביולוגיה של אורגניזמים רב תאיים מורכבים 2. בעיה זו החלה להיות מטופל על ידי הפיתוח של מיקרוסקופיה intravital (IVM) שפתחה את הדלת לבירורן של שאלות ביולוגיות מרכזיות בתחומים כמו נוירוביולוגיה, אימונולוגיה וגידול ביולוגיה 3. עד כה, רוב המחקרים המבוססים על IVM בוצעו ברמות של רקמות ותאים בודדים, מבלי לספק כל מידע על הדינמיקה של תאי subcellular. לאחרונה, המעבדה ואחרת שלנוים פיתחו טכניקות IVM מסוגלים מבני subcellular הדמיה במכרסמים חיים 4-7, 13-15 ומאפשרים מניפולציות תרופתי וגנטיות בגוף חי. גישה זו נוצלה בעבר על ידי לנו ללמוד סחר קרום in vivo, ובאופן ספציפי יותר אנדוציטוזה ומוסדרת exocytosis 6,7. מערכת המודל הניסויית שלנו מבוססת על חשיפה, ייצוב והדמית בלוטות רוק submandibular (SGS) של מכרסמים בהרדמה. הבחירה של SGS כאיבר מודל לIVM היא בשל העובדה שהבלוטות נגישות בקלות על ידי ביצוע ניתוח קטן, יכול להיות מוחצן מבלי להתפשר על הפיסיולוגיה שלהם, והתייצב כדי להפחית את חפצי התנועה בשל פעימות לב ונשימה. בנוסף, SGS ניתן להשפיע באופן סלקטיבי מבחינה גנטית על ידי הזרקת וקטורים מבוססים או ויראלי או לא ויראלי דרך צינור רוק 8,9. לבסוף, SGS הם בלוטות אקסוקרינית מורכבות מepith המקוטבתאי elial, המהווים את acini והצינוריות, תאי myoepithelial, ואוכלוסייה מורכבת של תאי סטרומה. מסיבה זו, הם מודל מצוין ללמוד exocytosis, אנדוציטוזה, מסירת גן, ושלד תא אקטין, מודגש כמו במחקרים האחרונים שלנו 10, ומציע את ההזדמנות ללמוד היבטים של ביולוגיה של תא, כגון קוטביות תא, חלוקת תא, תא צמתים תא, ותעלות יונים. במאמר זה אנו מתארים בפירוט פרוטוקול הדמיה להשגת הרזולוציה subcellular באפיתל של SGS של עכבר חי. באופן ספציפי, אנו מראים כיצד תמונת גרגרי ההפרשה בתאי acinar של SGS במהלך exocytosis המוסדר. כפי שניתן לראות בעבר, על גירוי עם אגוניסטים של הקולטן בטא adrenergic, גרגרי הפרשה להתמזג עם קרום הפלזמה הפסגה ויתמוטטו בהדרגה, משחררים את התוכן שלהם לcanaliculi acinar 6. המטרה שלנו היא לספק את הכלים הבסיסיים לחוקרים עם מ &#39;ניסיון inimal בפרוצדורות כירורגיות וטיפול בבעלי חיים, כך שהם יכולים לבצע בהצלחה IVM ברזולוציה subcellular. מאז החלק המאתגר ביותר בIVM הוא ההכנה של בעל החיים, כאן אנו מתמקדים בתיאור של פרוצדורות כירורגיות הבסיסיות שמנוצלות לחשוף ולשתק את SGS מבלי להתפשר על התפקוד שלהם. ובאשר לנהלים לתייג מבני subcellular, מספר אסטרטגיות, כגון משלוח מערכתי של בדיקות ניאון, שימוש בבעלי החיים מהונדסים, או שילוב של שניהם, כבר תאר במקום אחר 7,11.

<table border="1" fo:keep-together.within-page="always">
		<tbody>
		 <tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Reagent</td>
		 </tr>
		 <tr>
			<td>Isoflourane (Forane)</td>
			<td>Baxter</td>
			<td>101936-40</td>
			<td>Handle under chemical hood</td>
		 </tr>
		 <tr>
			<td>Ketamine (ketaved)</td>
			<td>Fort Dodge Animal Health</td>
			<td>57457-034-10</td>
			<td>Stock solution 100 mg/ml</td>
		 </tr>
		 <tr>
			<td>Xylazine (Anased)</td>
			<td>Akorn, Decatur</td>
			<td>61311-481-10</td>
			<td>Stock solution 100 mg/ml</td>
		 </tr>
		 <tr>
			<td>Neomycin/Polymyxin B</td>
			<td>Bausch and Lomb</td>
			<td>24208-785-55</td>
			<td>Use to lubricate the eye of the mouse</td>
		 </tr>
		 <tr>
			<td>Carbomer-940</td>
			<td>Ashalnd, Inc.</td>
			<td>4607-1</td>
			<td></td>
		 </tr>
		 <tr>
			<td>D-Sorbitol</td>
			<td>Sigma-Aldrich</td>
			<td>S1876</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Triethanolamine</td>
			<td>Sigma-Aldrich</td>
			<td>90279</td>
			<td>Add drop wise to prevent the solution to solidify</td>
		 </tr>
		 <tr>
			<td>Isoproternol</td>
			<td>Sigma-Aldrich</td>
			<td>16504</td>
			<td>Prepare fresh solutions in saline when needed. Stocks can be stored at -20 &deg;C</td>
		 </tr>
		 <tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Instrument</td>
		 </tr>
		 <tr>
			<td>Isoflurane V 1.9 (Vaporizer)</td>
			<td>Braintree Scientific</td>
			<td>190AF</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Portable Downdraft table equipped with HEPA filter</td>
			<td>Hazard Technology</td>
			<td>PDDT</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Heat lamp, Model HL1</td>
			<td>Braintree Scientific</td>
			<td>HL-1 US</td>
			<td></td>
		 </tr>
		 <tr>
			<td>MicroTherma 2T Thermometer</td>
			<td>Braintree Scientific</td>
			<td>TW2</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Operating Scissors (11.5 cm straight</td>
			<td>World Precision Instruments </td>
			<td>5003708-12</td>
			<td></td>
		 </tr>
		 <tr>
			<td>#7 curved tip tweezers</td>
			<td>World Precision Instruments</td>
			<td>14187</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Microscissors</td>
			<td>World Precision Instruments</td>
			<td>503365</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Black Braided Silk suture #4.0</td>
			<td>George &amp; Tiemann &amp; Co</td>
			<td>160-1219-4</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Gauze sponges 2" x 2"</td>
			<td>Tyco Healthcare</td>
			<td>9022</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Lens cleaning tissue</td>
			<td>Olympus</td>
			<td>CL-TISSUE (M97) AX6476</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

intravital microscopy for imaging subcellular structures in live mice expressing fluorescent proteins

כאן אנו מתארים הליך למבני subcellular תמונה במכרסמים חיים המבוססים על השימוש במיקרוסקופ intravital confocal. כאיבר מודל, אנו משתמשים בבלוטות הרוק של עכברים חיים מכיוון שהם מספקים מספר יתרונות. ראשית, הם יכולים להיחשף בקלות כדי לאפשר גישה לאופטיקה, והתייצבו כדי להקל על ההפחתה של ממצא התנועה בשל פעימות לב ונשימה. זה מקל באופן משמעותי הדמיה ומעקב אחר מבני subcellular קטנים. שנית, רוב אוכלוסיות התאים של בלוטות הרוק נגישים מפני שטח של האיברים. זה מאפשר השימוש במיקרוסקופיה confocal שיש לו רזולוציה מרחבית גבוהה יותר מטכניקות אחרות שהיה בשימוש במשך in vivo הדמיה, כגון שני פוטונים במיקרוסקופ. לבסוף, ניתן להשפיע על בלוטות רוק בקלות פרמקולוגית וגנטי, ובכך לספק מערכת חזקה כדי לחקור תהליכים ביולוגיים ברמה מולקולרית. במחקר זה אנו מתמקדים בפרוטוקול נועד לעקוב קינטיקה של exocytosis של גרגרי הפרשה בתאי acinar ואת הדינמיקה של קרום הפלזמה הפסגה שבו גרגרי הפרשת הפתיל על גירוי של קולטנים בטא adrenergic. באופן ספציפי, השתמשנו בעכבר מהונדס שישתף מבטא GFP cytosolic ופפטיד ממוקד קרום התמזגו עם חלבון טנדם-עגבניות ניאון. עם זאת, הנהלים ששמשנו לייצוב תמונה ובלוטות הרוק יכולים להיות מורחבים לדגמי עכבר אחרים ומצמידים את גישות אחרות לתווית רכיבים סלולריים in vivo, המאפשר ההדמיה של מבני subcellular שונים, כגון endosomes, lysosomes, מיטוכונדריה, ו שלד התא אקטין.

בעכבר ה-GFP / mTomato, acini מופיע מבנים כנבדלים באופן ברור, שמבטאים GFP cytosolic ופפטיד טנדם-עגבניות ממוקדות קרום (איור 2, קו שבור). בacini הבודד, תאי acinar מסומנים בפפטיד טנדם-עגבניות. GFP הוא גם זוהה בגרעינים שנראים בבירור בתוך תאי acinar (איור 2, חיצים). GFP cytosolic מוחרג מגרגי...

Watch this Scientific Journal Video about Intravital Microscopy for Imaging Subcellular Structures in Live Mice Expressing Fluorescent Proteins at JoVE.com

Intravital Microscopy for Imaging Subcellular Structures in Live Mice Expressing Fluorescent Proteins

מיקרוסקופיה Intravital היא כלי רב עוצמה המאפשר הדמיה של תהליכים ביולוגיים שונים בבעלי חיים. במאמר זה, אנו מציגים שיטה מפורטת להדמית הדינמיקה של מבני subcellular, כגון גרגרי ההפרשה, בבלוטות הרוק של עכברים חיים.

מיקרוסקופית Intravital למבני ההדמיה subcellular בעכברים חיים לבטא חלבוני פלורסנט

Here we describe a procedure to image subcellular structures in live rodents that is based on the use of confocal intravital microscopy. As a model organ, ...

intravital-microscopy-for-imaging-subcellular-structures-live-mice

Research

JoVE Journal

Biology

23.5K Views.  National Institutes of Health.  מיקרוסקופיה Intravital היא כלי רב עוצמה המאפשר הדמיה של תהליכים ביולוגיים שונים בבעלי חיים. במאמר זה, אנו מציגים שיטה מפורטת להדמית הדינמיקה של מבני subcellular, כגון גרגרי ההפרשה, בבלוטות הרוק של עכברים חיים. 

Video: Intravital Microscopy for Imaging Subcellular Structures in Live Mice Expressing Fluorescent Proteins

Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy (FSM)

In this protocol we describe the use of Fluorescent Speckle Microscopy (FSM) to capture high-resolution images of actin dynamics in PtK1 cells. A unique advantage of FSM is its ability to capture the movement and turnover kinetics (assembly/disassembly) of the F-actin network within living cells. This technique is particularly useful in deriving quantitative measurements of F-actin dynamics when paired with computer vision software (qFSM).  We describe  the selection, microinjection and visualization of fluorescent actin probes in living cells. Importantly, similar procedures are applicable to visualizing other macomolecular assemblies. FSM has been demonstrated for microtubules, intermediate filaments, and adhesion complexes.  

Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM

Selection, microinjection, and imaging of fluorescently-labeled F-actin via fluorescent speckle microscopy (FSM).

דימות של תא חי F-אקטין Dynamics באמצעות פלורסנט מיקרוסקופית רבב (FSM)

In this protocol we describe the use of Fluorescent Speckle Microscopy (FSM) to capture high-resolution images of actin dynamics in PtK1 cells. A unique ...

Fluorescent Labeling of Drosophila Heart Structures

The Drosophila melanogaster dorsal vessel, or heart, is a tubular structure comprised of a single layer of contractile cardiomyocytes, pericardial cells that align along each side of the heart wall, supportive alary muscles and, in adults, a layer of ventral longitudinal muscle cells. The contractile fibers house conserved constituents of the muscle cytoarchitecture including densely packed bundles of myofibrils and cytoskeletal/submembranous protein complexes, which interact with homologous components of the extracellular matrix. Here we describe a protocol for the fixation and the fluorescent labeling of particular myocardial elements from the hearts of dissected larvae and semi-intact adult Drosophila. Specifically, we demonstrate the labeling of sarcomeric F-actin and of &alpha;-actinin in larval hearts. Additionally, we perform labeling of F-actin and &alpha;-actinin in myosin-GFP expressing adult flies and of &alpha;-actinin and pericardin, a type IV extracellular matrix collagen, in wild type adult hearts. Particular attention is given to a mounting strategy for semi-intact adult hearts that minimizes handling and optimizes the opportunity for maintaining the integrity of the cardiac tubes and the associated tissues. These preparations are suitable for imaging via fluorescent and confocal microscopy. Overall, this procedure allows for careful and detailed analysis of the structural characteristics of the heart from a powerful genetically tractable model system.

Fluorescent Labeling of Drosophila Heart Structures

Here we describe a basic protocol for fluorescent labeling of different elements of heart tubes from larva and adult Drosophila melanogaster. These specimens are well-suited for imaging via fluorescent or confocal microscopy. This technique permits detailed structural analysis of the features of the hearts from a powerful model organism.

תיוג של פלורסנט תסיסנית לב מבנים

The Drosophila melanogaster dorsal vessel, or heart, is a tubular structure comprised of a single layer of contractile cardiomyocytes, pericardial cells ...

Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging

SNAP-tag and CLIP-tag protein labeling systems enable the specific, covalent attachment of molecules, including fluorescent dyes, to a protein of interest in live cells. These systems offer a broad selection of fluorescent substrates optimized for a range of imaging instrumentation. Once cloned and expressed, the tagged protein can be used with a variety of substrates for numerous downstream applications without having to clone again. There are two steps to using this system: cloning and expression of the protein of interest as a SNAP-tag fusion, and labeling of the fusion with the SNAP-tag substrate of choice. The SNAP-tag is a small protein based on human O6-alkylguanine-DNA-alkyltransferase (hAGT), a DNA repair protein. SNAP-tag labels are dyes conjugated to guanine or chloropyrimidine leaving groups via a benzyl linker. In the labeling reaction, the substituted benzyl group of the substrate is covalently attached to the SNAP-tag. CLIP-tag is a modified version of SNAP-tag, engineered to react with benzylcytosine rather than benzylguanine derivatives. When used in conjunction with SNAP-tag, CLIP-tag enables the orthogonal and complementary labeling of two proteins simultaneously in the same cells.

SNAP-tag and CLIP-tag protein labeling systems enable the specific, covalent attachment of molecules, including fluorescent dyes, to a protein of interest in live cells. Once cloned and expressed, the tagged protein can be used with a variety of substrates for numerous downstream applications without having to clone again.

תיוג פלורסנט של COS-7-SNAP הבעת תג חלבונים Fusion עבור דימות תא חי

SNAP-tag and CLIP-tag protein labeling systems enable the specific, covalent attachment of molecules, including fluorescent dyes, to a protein of interest ...

Transplantation of GFP-expressing Blastomeres for Live Imaging of Retinal and Brain Development in Chimeric Zebrafish Embryos

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their environment. Chimeric embryos, which are composed of cells of different genetic background, are great tools to study the cell-cell interactions mediated by genes of interest. The embryonic transparency of zebrafish at early developmental stages permits direct visualization of the morphogenesis of tissues and organs at the cellular level. Here, we demonstrate a protocol to generate chimeric retinas and brains in zebrafish embryos and to perform live imaging of the donor cells. The protocol covers the preparation of transplantation needles, the transplantation of GFP-expressing donor blastomeres to GFP-negative hosts, and the examination of donor cell behavior under live confocal microscopy. With slight modifications, this protocol can also be used to study the embryonic development of other tissues and organs in zebrafish. The advantages of using GFP to label donor cells are also discussed. 

We demonstrate a protocol to generate chimeric zebrafish embryos for live imaging cellular behavior during embryogenesis.

השתלה של ה-GFP-לבטא בלסטומרים עבור הדמיה חיה של התפתחות המוח ואת רשתית עוברי דג הזברה chimeric

Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their ...

Photoconversion of Purified Fluorescent Proteins and Dual-probe Optical Highlighting in Live Cells

Photoconvertible fluorescent proteins (pc-FPs) are a class of fluorescent proteins with "optical highlighter" capability, meaning that the color of fluorescence can be changed by exposure to light of a specific wavelength. Optical highlighting allows noninvasive marking of a subpopulation of fluorescent molecules, and is therefore ideal for tracking single cells or organelles.
Critical parameters for efficient photoconversion are the intensity and the exposure time of the photoconversion light. If the intensity is too low, photoconversion will be slow or not occur at all. On the other hand, too much intensity or too long exposure can photobleach the protein and thereby reduce the efficiency of photoconversion.
This protocol describes a general approach how to set up a confocal laser scanning microscope for pc-FP photoconversion applications. First, we describe a procedure for preparing purified protein droplet samples. This sample format is very convenient for studying the photophysical behavior of fluorescent proteins under the microscope. Second, we will use the protein droplet sample to show how to configure the microscope for photoconversion. And finally, we will show how to perform optical highlighting in live cells, including dual-probe optical highlighting with mOrange2 and Dronpa.

This protocol describes a general approach to perform photoconversion of fluorescent proteins on a confocal laser scanning microscope. We describe procedures for the photoconversion of puried protein samples, as well as for dual-probe optical highlighting in live cells with mOrange2 and Dronpa.

Photoconversion של חלבונים מטוהרים פלורסנט ו Dual-בדיקה אופטי סימון בתאים חיים

Photoconvertible fluorescent proteins (pc-FPs) are a class of fluorescent proteins with "optical highlighter" capability, meaning that the color of ...

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes1,2.
The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis3,4. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent5 and provides a useful system for investigating cytoskeleton function at these stages.
Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup.

Live Imaging of GFP-labeled Proteins in Drosophila Oocytes

A protocol for live imaging of GFP-tagged proteins or autofluorescent structures in individual Drosophila oocytes is described.

חי הדמיה של חלבוני ה-GFP שהכותרת ב-<em&gt; דרוזופילה</em&gt; ביציות

The  Drosophila oocyte has been established as a versatile system for investigating  fundamental questions such as cytoskeletal function, cell ...

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and temporal resolution to study in vivo hematopoiesis using the murine bone marrow transplant experimental model. Genetic combinatorial marking using lentiviral vectors encoding fluorescent proteins (FPs) enabled cell fate mapping through advanced microscopy imaging. Vectors encoding five different FPs: Cerulean, EGFP, Venus, tdTomato, and mCherry were used to concurrently transduce HSPCs, creating a diverse palette of color marked cells. Imaging using confocal/two-photon hybrid microscopy enables simultaneous high resolution assessment of uniquely marked cells and their progeny in conjunction with structural components of the tissues. Volumetric analyses over large areas reveal that spectrally coded HSPC-derived cells can be detected non-invasively in various intact tissues, including the bone marrow (BM), for extensive periods of time following transplantation. Live studies combining video-rate multiphoton and confocal time-lapse imaging in 4D demonstrate the possibility of dynamic cellular and clonal tracking in a quantitative manner.

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

Combinatorial 5 fluorescent proteins marking of hematopoietic stem and progenitor cells allows in vivo clonal tracking via confocal and two-photon microscopy, providing insights into bone marrow hematopoietic architecture during regeneration. This method allows non-invasive fate mapping of spectrally-coded HSPCs-derived cells in intact tissues for extensive periods of time following transplantation.

במשובט מעקב vivo של גזע hematopoietic ובתאים המסומנים על ידי חמישה חלבונים ניאון באמצעות Confocal וmultiphoton מיקרוסקופית

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and ...

Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy

Apart from their essential role in generating ATP, mitochondria also act as local calcium (Ca2+) buffers to tightly regulate intracellular Ca2+ concentration. To do this, mitochondria utilize the electrochemical potential across their inner membrane (&#916;&#936;m) to sequester Ca2+. The influx of Ca2+ into the mitochondria stimulates three rate-limiting dehydrogenases of the citric acid cycle, increasing electron transfer through the oxidative phosphorylation (OXPHOS) complexes. This stimulation maintains &#916;&#936;m, which is temporarily dissipated as the positive calcium ions cross the mitochondrial inner membrane into the mitochondrial matrix.
We describe here a method for simultaneously measuring mitochondria Ca2+ uptake and &#916;&#936;m in live cells using confocal microscopy. By permeabilizing the cells, mitochondrial Ca2+ can be measured using the fluorescent Ca2+ indicator Fluo-4, AM, with measurement of &#916;&#936;m using the fluorescent dye tetramethylrhodamine, methyl ester, perchlorate (TMRM). The benefit of this system is that there is very little spectral overlap between the fluorescent dyes, allowing accurate measurement of mitochondrial Ca2+ and &#916;&#936;m simultaneously. Using the sequential addition of Ca2+ aliquots, mitochondrial Ca2+ uptake can be monitored, and the concentration at which Ca2+ induces mitochondrial membrane permeability transition and the loss of &#916;&#936;m determined.

Mitochondria can utilize the electrochemical potential across their inner membrane (&#916;&#936;m) to sequester calcium (Ca2+), allowing them to shape cytosolic Ca2+ signaling within the cell. We describe a method for simultaneously measuring mitochondria Ca2+ uptake and &#916;&#936;m in live cells using fluorescent dyes and confocal microscopy.

מדידה בו זמנית של סידן מיטוכונדריאלי מיטוכונדריאלי ממברנה פוטנציאלית בתאים חיים באמצעות פלורסנט מיקרוסקופית

Apart from their essential role in generating ATP, mitochondria also act as local calcium (Ca2+) buffers to tightly regulate intracellular Ca2+ ...

Fluorescence Recovery after Photobleaching of Yellow Fluorescent Protein Tagged p62 in Aggresome-like Induced Structures

Fluorescence recovery after photobleaching (FRAP)&#160;is a microscopy technique that can be used to quantify protein mobility in live cells. In a typical FRAP experiment, steady-state fluorescence is observed by repeated imaging with low-intensity laser light. Subsequently, the fluorescent molecules are rapidly and irreversibly impaired via brief exposure to high-intensity laser light. Information about protein mobility is obtained by monitoring the recovery of fluorescence. We used FRAP to determine the mobility of p62 in aggresome-like induced structures (ALIS) in murine macrophages after stimulation with lipopolysaccharide (LPS). Because many existing FRAP protocols are either incomplete or complex, our goal was to provide a comprehensive, practical, and straightforward step-by-step protocol for FRAP experiments with live cells. Here, we describe RAW264.7 macrophage transfection with yellow fluorescent protein-p62 (YFP-p62), induction of ALIS by exposing the cells to LPS, and a step-by-step method for collecting prebleach and postbleach FRAP images and data analysis. Finally, we discuss important factors to consider when conducting a FRAP experiment.

We describe a comprehensive and practical protocol for fluorescence recovery after photobleaching experiments with live cells. Although the protocol was used to measure the mobility of yellow fluorescent protein-tagged p62 in aggresome-like induced structures, it can be applied to a variety of microscopy systems and fluorescent proteins.

קרינה פלואורסצנטית התאוששות לאחר Photobleaching של צהוב הניאון חלבון מתויג p62 במבנים המושרה כמו Aggresome

Fluorescence recovery after photobleaching (FRAP)&#160;is a microscopy technique that can be used to quantify protein mobility in live cells. In a typical ...

Super-Resolution Live Cell Imaging of Subcellular Structures

There has long been a crucial tradeoff between spatial and temporal resolution in imaging. Imaging beyond the diffraction limit of light has traditionally been restricted to be used only on fixed samples or live cells outside of tissue labeled with strong fluorescent signal. Current super-resolution live cell imaging techniques require the use of special fluorescence probes, high illumination, multiple image acquisitions with post-acquisition processing, or often a combination of these processes. These prerequisites significantly limit the biological samples and contexts that this technique can be applied to.
Here we describe a method to perform super-resolution (~140 nm XY-resolution) time-lapse fluorescence live cell imaging in situ. This technique is also compatible with low fluorescent intensity, for example, EGFP or mCherry endogenously tagged at lowly expressed genes. As a proof-of-principle, we have used this method to visualize multiple subcellular structures in the Drosophila testis. During tissue preparation, both the cellular structure and tissue morphology are maintained within the dissected testis. Here, we use this technique to image microtubule dynamics, the interactions between microtubules and the nuclear membrane, as well as the attachment of microtubules to centromeres.
This technique requires special procedures in sample preparation, sample mounting and immobilizing of specimens. Additionally, the specimens must be maintained for several hours after dissection without compromising cellular function and activity. While we have optimized the conditions for live super-resolution imaging specifically in Drosophila male germline stem cells (GSCs) and progenitor germ cells in dissected testis tissue, this technique is broadly applicable to a variety of different cell types. The ability to observe cells under their physiological conditions without sacrificing either spatial or temporal resolution will serve as an invaluable tool to researchers seeking to address crucial questions in cell biology.

Presented here is a protocol for super-resolution live-cell imaging in intact tissue. We have standardized the conditions for imaging a highly sensitive adult stem cell population in its native tissue environment. This technique involves balancing temporal and spatial resolution to allow for the direct observation of biological phenomena in live tissue.

הדמיית תאים חיים ברזולוציה סופר-רזולוציה של מבנים תת-תאיים

There has long been a crucial tradeoff between spatial and temporal resolution in imaging. Imaging beyond the diffraction limit of light has traditionally ...