CQS receives a fellowship from the LOEWE Excellence Cluster for Integrative Fungal Research (IPF). The author would like to thank Ida J. van der Klei for the P. chrysogenum strains used in this work and Andreas S. Reichert for the gift of rapamycin.

P. hazırlanması 1. chrysogenum Açlık Deneyler için <ol><li> P. Eğer Çevrede chrysogenum suşu pirinç (&#39;yeşil pirinç&#39;) tutulur, 1.5 ml mikrosantrifüj tüp içine miselyumu sporlanan ile kaplı 2-3 pirinç tanelerini yerleştirin. 500 ul YGG (10 g / l KCI, 20 g / l glukoz, 10 g / l maya azot baz, 5 g / l K 2 HPO 4, 20 g / l maya ekstresi) ile doldurun. <ol><li> Sporlar etkili bir pirinç ayrılacak şekilde 30 saniye için tüp karıştırın. </li><li> Oda sıcaklığında 1 gün (örneğin, 20 ila 25 ° C) tüp inkübe edin. </li><li> Steril musluk suyu bu spor süspansiyonu, bir 1/50 seyreltme hazırlanır, iyice karıştırın. </li></ol></li><li> P. Eğer Çevrede chrysogenum suşu bir agar plaka (örneğin, YGG agar) tutulur, 400 ul steril musluk suyu ve yaklaşık 100 mg gl içeren 1.5 ml mikrosantrifüj tüp içine misel küçük parçalar aktarmaksteril bir kürdan veya pipet kullanarak eşek boncuk. <ol><li> Vortex 2 dakika süreyle tüp böylece misel parçalanmış olur. Hemen tüp içeriğini kullanın. </li></ol></li></ol> P. Yetiştiriciliği 2. Hazırlık Adımları Açlık Pedleri üzerinde chrysogenum <ol><li> Bir ısıtma plakası üzerinde açma ve yaklaşık 60 ° C&#39;ye ayarlayın. </li><li> Bir mikrodalga fırında pişirme çözümü ile musluk suyu ml 100&#39;de agaroz 2 gr eritin. Bu çözüm ısıttıktan sonra tamamen açıktır özen gösterin. Değilse agaroz tamamen eriyene kadar, tekrar pişirin. Agaroz çözüm kullanılmadan önce yaklaşık 60 ° C&#39;ye kadar soğumasını bekleyin. </li><li> 400 ul steril musluk her (ek bileşikler eklenmiştir) su ya da (örneklerin sayısına bağlı olarak 2-4) 1.5 ml mikrosantrifüj tüpleri Dolgu 400 x ul (adım 2.5 bileşiği çözeltisi ul x ilaveli) ve koyun en az 1 dakika için ısıtma plakası üzerine bu yüzden water içinde ısınıyor. </li><li> En az 1 dakika için ısıtma plakası üzerine bir merkezi boşluğu içeren mikroskop slayt yerleştirin. </li><li> 1.5 ml mikrosantrifüj tüpleri ve girdap kısaca çözeltisine agaroz 400 ul% 2 ekleyin. Eğer istenirse bu adımdan sonra ilave bileşikler (yani, 1 uM rapamisin) ekleyin. Eğer bu yapılırsa, girdap her ek madde tüp pipetle kısaca sonra. Erken katılaşma önlemek için ısıtma masaya geri tüpleri koyun. NOT: mikrosantrifüj tüpü içinde toplam hacim 800 ul olmalıdır. </li></ol> Açlık Pedleri İçeren Mikroskop Slaytlar 3. Hazırlık <ol><li> (Hala ısıtma plakası üzerinde yer almaktadır) mikroskop lamı boşluğuna agaroz çözeltisi Pipet 140 ul. Mümkünse kabarcıkları yapmaktan kaçınmaya çalışın. </li><li> Hemen agaroz çözeltisi üzerine bir kapak kayma yerleştirin. Not: Bu, düz bir yüzeye yol açacaktır. </li><li> Mikro koyYaklaşık 4 dakika laboratuar tezgah üzerine kapsam slayt agaroz ped katılaşmaya izin. </li><li> Dikkatlice başparmak veya işaret parmağı yardımı ile kaymasını agaroz ped lamel çıkarın (kirlenmeyi önlemek için eldiven giymek!). </li><li> Kurumasını önlemek için bir ıslak odasına ped ile mikroskop lamı yerleştirin. Öneri: hala pipet uçları tutmak için ekleme sahip boş bir ipucu kutusunu kullanın. Alt tutulmasını sağlamak için, kutu, steril su eklenir. Insert üzerine mikroskop slaytlar yerleştirin ve kutusunu kapatın. </li></ol> 4. P. ile Açlık Pedleri aşılamak chrysogenum Kuluçka <ol><li> 1/50 spor (kültürler pirinç yetiştirilen olsaydı) seyreltme veya açlık pad merkezine üzerine (kültürler bir agar plaka üzerinde yetiştirilen olsaydı) misel parçalarını içeren sulandırılmamış çözeltinin 5 ul Pipet 5 ul. </li><li> Bu şekilde hizmet vermektedir (ıslak odasına kapatın ve bir plastik torba içinde sarınaçlık yastıkları kuruma karşı ek koruma). Çok aksi aşılama damla rahatsız olacak, çünkü kutusunu taşımak için dikkatli olun. </li><li> Örnekleri analiz etmek için en az 20 saat boyunca oda sıcaklığında sarılmış kutusunu saklayın. </li></ol> Örneklerinde 5. mikroskobik analizi <ol><li> Inkübasyon 20 saat sonra numuneler mikroskobik analiz için hazır; Kuru kağıt mendil üzerine mikroskop lamı koyun (alt ıslak olma eğilimindedir). </li><li> Açlık ped üzerine küçük bir su hacmi (yaklaşık 50 ul) pipetle. Ped üzerine bir lamel koyun ve fazla suyunu sıkın. Bir kağıt mendil ile fazla suyun çıkarın. </li><li> Floresan mikroskop gözlem masaya mikroskop lamı koyun. Misel büyüme bir bakış elde etmek için, bir 20X objektif kullanın. Hif GFP lokalizasyonu incelemek için kullanın 63X veya 100X hedefleri. Için numune analiz yok numune kademeli kuruma önlemek içinuzun 15 dakika ıslak odasına geri koymadan önce. </li><li> (40 saat ve büyüme 60 saat sonra, örneğin) düzenli aralıklarla 5.3 tekrarlayın. NOT: Numune ıslak odasına geri konabilir. O Miseliyum büyümeyi etkilemez gibi lamel kaldırmak için gerekli değildir. </li></ol>

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	<li>Fischer, F., Hamann, A., Osiewacz, H. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+quality+control:+an+integrated+network+of+pathways.">Mitochondrial quality control: an integrated network of pathways.</a> Trends Biochem. Sci. 37 (7), 284-292 (2012).</li><li>Pollack, J. K., Harris, S. D., Marten, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autophagy+in+filamentous+fungi.">Autophagy in filamentous fungi.</a> Fungal Genet. Biol. 46 (1), 1-8 (2009).</li><li>Scheckhuber, C. Q., Osiewacz, H. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Podospora+anserina:+a+model+organism+to+study+mechanisms+of+healthy+ageing.">Podospora anserina: a model organism to study mechanisms of healthy ageing.</a> Mol. Genet. Genomics. 280 (5), 365-374 (2008).</li><li>Pinan-Lucarr&#233;, B., Iraqui, I., Clav&#233;, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Podospora+anserina+target+of+rapamycin.">Podospora anserina target of rapamycin.</a> Curr. Genet. 50 (1), 23-31 (2006).</li><li>Kikuma, T., Ohneda, M., Arioka, M., Kitamoto, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+analysis+of+the+ATG8+homologue+Aoatg8+and+role+of+autophagy+in+differentiation+and+germination+in+Aspergillus+oryzae.">Functional analysis of the ATG8 homologue Aoatg8 and role of autophagy in differentiation and germination in Aspergillus oryzae.</a> Eukaryot. Cell. 5 (8), 1328-1336 (2006).</li><li>Pinan-Lucarr&#233;, B., Balguerie, A., Clav&#233;, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accelerated+cell+death+in+Podospora+autophagy+mutants.">Accelerated cell death in Podospora autophagy mutants.</a> Eukaryot. Cell. 4 (11), 1765-1774 (2005).</li><li>Veneault-Fourrey, C., Barooah, M., Egan, M., Wakley, G., Talbot, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autophagic+fungal+cell+death+is+necessary+for+infection+by+the+rice+blast+fungus.">Autophagic fungal cell death is necessary for infection by the rice blast fungus.</a> Science. 312 (5773), 580-583 (2006).</li><li>Bartoszewska, M., Kiel, J. A., Bovenberg, R. A., Veenhuis, M., van der Klei, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autophagy+deficiency+promotes+beta-lactam+production+in+Penicillium+chrysogenum.">Autophagy deficiency promotes beta-lactam production in Penicillium chrysogenum.</a> Appl. Environ. Microbiol. 77 (4), 1413-1422 (2011).</li><li>Meijer, W. H., 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=Peroxisomes+are+required+for+efficient+penicillin+biosynthesis+in+Penicillium+chrysogenum.">Peroxisomes are required for efficient penicillin biosynthesis in Penicillium chrysogenum.</a> Appl. Environ. Microbiol. 76 (17), 5702-5709 (2010).</li><li>Cubitt, A. B., Heim, R., Adams, S. R., Boyd, A. E., Gross, L. A., Tsien, R. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding,+improving+and+using+green+fluorescent+proteins.">Understanding, improving and using green fluorescent proteins.</a> Trends Biochem. Sci. 20 (11), 448-455 (1995).</li><li>Jung, C. H., Ro, S. H., Cao, J., Otto, N. M., Kim, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=mTOR+regulation+of+autophagy.">mTOR regulation of autophagy.</a> FEBS Lett. 584 (7), 1287-1295 (2010).</li><li>Hickey, P. C., Read, N. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+living+cells+of+Aspergillus+in+vitro.">Imaging living cells of Aspergillus in vitro.</a> Med. Mycol. 47, S110-S119 (2009).</li></ol>

The author has nothing to disclose.

Burada sunulan yöntem, P. otofaji uygun ve tekrarlanabilir çalışma sağlar chrysogenum. Örneğin, bu mantar ya da değil Otofaji tepkisini modüle edebilen olup çeşitli bileşiklerin etkinliğini taramak için kullanılabilir. rapamisin ile sonuçlar Devri sinyallemesinin engellenmesi P. otofaji belirgin bir indüksiyonuna neden olduğunu göstermektedir chrysogenum, diğer organizmalar 11 kanıtlanabildiği. Daha karmaşık mikroskoplar?...

İpliksi mantar gelişme işlemine çalışma için mükemmel bir model sistemleridir. Bunlar ucuz ekimi, döl ve genetik erişilebilirlik yüksek sayılar gibi birçok deneysel faydaları sunuyoruz. son nokta, çeşitli hücresel mekanizmalar için çok-çok uncharacterized genlerin önemini araştıran izin Transformantların yapımı için özellikle önemlidir. İpliksi mantar fazlası ve / veya işlevsel hücre bileşenlerinin çıkarılması için mitokondriyal bütünlüğü ve Otofaji sağlamak ve sürdürmek için çeşitli elemanlar ve anormal protein, mitokondriyal dinamikleri indirgenmesi için proteaz aktivitesi hücresel kalite kontrol yollarının mekanizmaların açıklanması için etkili olmuştur açlık 1,2,3 zamanlarında hücre canlılığı. Ipliksi mantarlar 2 Otofaji çalışma için uygun bir çok deneysel teknik vardır: vaküol (i) inceleme ıproteazlar, transmisyon elektron mikroskopisi 4 tarafından önlendiği zaman f de yoğun otofajik organları içeren, (ii) flüoresan boya monodansyl kadavenn kullanılarak floresan mikroskop 5,6 ve asidifiye autophagosomal yapıları (iii) algılama ile GFP Atg8 odak izleyerek autophagosomes görselleştirme 7. Burada, otofaji çalışmaları için penicillium chrysogenum büyüyen yeni bir yöntem sunulmaktadır. Ana unsur sadece agaroz sterilize musluk suyunda çözünmüş 1% oluşur &#39;açlık pedi&#39; olduğunu. Ek bileşikler (örneğin, stres, temizleyiciler, otofaji modülatörleri) sürece otomatik floresan göstermez altlığınızda ilave edilebilir. ped sığ merkezi boşluğu ihtiva mikroskop slaytlar yer almaktadır. Bir spor süspansiyonu ile ya da küçük miselyum fragmanları ile aşılanır Bu ped. ilgi suşu sporulat başarısız olursa ikinci tavsiye ediliretkin bir şekilde, e (örneğin, Δ atg1 suşları 8). slaytlar numunenin kuruma önlemek için (bunlar kolayca boş pipet ucu kutuları kullanılarak inşa edilebilir) ve oda sıcaklığında inkübe ıslak odalarında konumlandırılmış. P. chrysogenum, bu koşullar altında bir kaç gün için büyümeye edebilmektedir. Otofaji mantar Otofaji için olumlu bir belirtecidir vakuolar genişleme ile mikroskobik edilebilir. Bu katkı, bir P. chrysogenum soyu (Wisconsin 54-1255) C-terminal &#39;SKL&#39; dizisi 9 ile peroksisomlara hedeflenen yeşil floresan proteini oluşturan kullanılır. Bu nedenle, peroksizom bozulmasını izlemek mümkündür. Uygun lokalizasyon sinyallerini kullanarak, aynı zamanda hücrenin (örneğin, mitokondriya) &#39;in diğer bölmeleri etiket ve bozunmasını analiz etmek mümkündür. P. veri rağmen chrysogenum Ws54-1255 (GFP-SKL) kesinlikle mümkün, burada sunulmuşturDiğer ipliksi mantarlar için de &#39;açlık ped&#39; yöntemi kullanmak (örneğin, Neurospora crassa, Sordaria macrospora, Aspergillus türleri, vb).

<table><tbody><tr><td>Microscope slides with central cavity</td><td>Carl Roth GmbH, Karlsruhe, Germany</td><td>H884.1</td><td>These can be used multiple times after cleaning.</td></tr><tr><td>Glass beads</td><td>Carl Roth GmbH, Karlsruhe, Germany</td><td>A553.1</td><td>Diameter: 0.25 - 0.50 mm</td></tr></tbody></table>

analysis of autophagy in penicillium chrysogenum by using starvation pads in combination with fluorescence microscopy

The study of cellular quality control systems has emerged as a highly dynamic and relevant field of contemporary research. It has become clear that cells possess several lines of defense against damage to biologically relevant molecules like nucleic acids, lipids and proteins. In addition to organelle dynamics (fusion/fission/motility/inheritance) and tightly controlled protease activity, the degradation of surplus, damaged or compromised organelles by autophagy (cellular &#8216;self-eating&#8217;) has received much attention from the scientific community. The regulation of autophagy is quite complex and depends on genetic and environmental factors, many of which have so far not been elucidated. Here a novel method is presented that allows the convenient study of autophagy in the filamentous fungus Penicillium chrysogenum. It is based on growth of the fungus on so-called &#8216;starvation pads&#8217; for stimulation of autophagy in a reproducible manner. Samples are directly assayed by microscopy and evaluated for autophagy induction / progress. The protocol presented here is not limited for use with P. chrysogenum and can be easily adapted for use in other filamentous fungi.

P. peroksizom bozulması yukarıda ayrıntılı protokol kullanılmasını göstermek için chrysogenum suşu Ws54-1255 (GFP-SKL) analiz edildi. Bu gerginlik GFP-SKL genellikle peroksizom 9 aktarılır. Örnek floresan mikroskobu ile analiz edildiğinde, bu çok sayıda küresel şekiller görünümüne yol açar. Otofaji oluşursa, vakuolleri büyütmek. GFP-SKL otofaji (pexophagy) tarafından vakuollerde dahil olur. Nedeniyle GFP vakuol proteazlar tarafından bozulmaya dirençli olduğu ge...

Watch this Scientific Journal Video about Analysis of Autophagy in Penicillium chrysogenum by Using Starvation Pads in Combination With Fluorescence Microscopy at JoVE.com

Analysis of Autophagy in Penicillium chrysogenum by Using Starvation Pads in Combination With Fluorescence Microscopy

A convenient and powerful method for studying autophagy in Penicillium chrysogenum by using starvation pads (mixtures of agarose and tap water in a microscope slide containing a central cavity) is presented here.

Otofaji Analiz<em&gt; Penicillium chrysogenum</em&gt; Floresan Mikroskopi ile Kombinasyon Açlık Pedleri kullanarak

The study of cellular quality control systems has emerged as a highly dynamic and relevant field of contemporary research. It has become clear that cells ...

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Biology

Analysis of Autophagy in Penicillium chrysogenum by Using Starvation Pads in Combination With Fluorescence Microscopy

8.5K Görüntüleme.  Senckenberg Research Institute. A convenient and powerful method for studying autophagy in Penicillium chrysogenum by using starvation pads (mixtures of agarose and tap water in a microscope slide containing a central cavity) is presented here.

Video: Analysis of Autophagy in Penicillium chrysogenum by Using Starvation Pads in Combination With Fluorescence Microscopy

Cecal Ligation and Puncture-induced Sepsis as a Model To Study Autophagy in Mice

Experimental sepsis can be induced in mice using the cecal ligation and puncture (CLP) method, which causes polymicrobial sepsis. Here, a protocol is provided to induce sepsis of varying severity in mice using the CLP technique. Autophagy is a fundamental tissue response to stress and pathogen invasion. Two current protocols to assess autophagy in vivo in the context of experimental sepsis are also presented here. (I) Transgenic mice expressing green fluorescence protein (GFP)-LC3 fusion protein are subjected to CLP. Localized enhancement of GFP signal (puncta), as assayed either by immunohistochemical or confocal assays, can be used to detect enhanced autophagosome formation and, thus, altered activation of the autophagy pathway. (II) Enhanced autophagic vacuole (autophagosome) formation per unit tissue area (as a marker of autophagy stimulation) can be quantified using electron microscopy. The study of autophagic responses to sepsis is a critical component of understanding the mechanisms by which tissues respond to infection. Research findings in this area may ultimately contribute towards understanding the pathogenesis of sepsis, which represents a major problem in critical care medicine.

Experimental sepsis can be induced in mice using the cecal ligation and puncture (CLP) method. Current protocols to assess autophagy in vivo in the context of CLP-induced sepsis are presented here: A protocol for measuring autophagy using (GFP)-LC3 mice, and a protocol for measuring autophagosome formation by electron microscopy.

Çekal ligasyon ve Farelerde Autophagy incelemek için bir model olarak Sepsis Patamaya kaynaklı

Experimental sepsis can be induced in mice using the cecal ligation and puncture (CLP) method, which causes polymicrobial sepsis. Here, a protocol is ...

İmmünoloji ve Enfeksiyon

A Fluorescence Microscopy Assay for Monitoring Mitophagy in the Yeast Saccharomyces cerevisiae

Autophagy is important for turnover of cellular components under a range of different conditions. It serves an essential homeostatic function as well as a quality control mechanism that can target and selectively degrade cellular material including organelles1-4. For example, damaged or redundant mitochondria (Fig. 1), not disposed of by autophagy, can represent a threat to cellular homeostasis and cell survival. In the yeast, Saccharomyces cerevisiae, nutrient deprivation (e.g., nitrogen starvation) or damage can promote selective turnover of mitochondria by autophagy in a process termed mitophagy 5-9.
We describe a simple fluorescence microscopy approach to assess autophagy. For clarity we restrict our description here to show how the approach can be used to monitor mitophagy in yeast cells. The assay makes use of a fluorescent reporter, Rosella, which is a dual-emission biosensor comprising a relatively pH-stable red fluorescent protein linked to a pH-sensitive green fluorescent protein. The operation of this reporter relies on differences in pH between the vacuole (pH ~ 5.0-5.5) and mitochondria (pH ~ 8.2) in living cells. Under growing conditions, wild type cells exhibit both red and green fluorescence distributed in a manner characteristic of the mitochondria. Fluorescence emission is not associated with the vacuole. When subjected to nitrogen starvation, a condition which induces mitophagy, in addition to red and green fluorescence labeling the mitochondria, cells exhibit the accumulation of red, but not green fluorescence, in the acidic vacuolar lumen representing the delivery of mitochondria to the vacuole. Scoring cells with red, but not green fluorescent vacuoles can be used as a measure of mitophagic activity in cells5,10-12.

A Fluorescence Microscopy Assay for Monitoring Mitophagy in the Yeast Saccharomyces cerevisiae

A robust approach to monitor the delivery of organelles to the acidic lumen of the yeast vacuole for degradation and recycling is described. The method relies on the specific labeling of target organelles with a genetically encoded dual-emission fluorescence pH-biosensor, and visualization of individual cells using fluorescence microscopy.

Maya İzleme Mitophagy Floresan Mikroskopi Testi Saccharomyces cerevisiae

Autophagy is important for turnover of cellular components under a range of different conditions. It serves an essential homeostatic function as well as a ...

Biyoloji

Quantitative Cell Biology of Neurodegeneration in Drosophila Through Unbiased Analysis of Fluorescently Tagged Proteins Using ImageJ

With the rising prevalence of neurodegenerative diseases, it is increasingly important to understand the underlying pathophysiology that leads to neuronal dysfunction and loss. Fluorescence-based imaging tools and technologies enable unprecedented analysis of subcellular neurobiological processes, yet there is still a need for unbiased, reproducible, and accessible approaches for extracting quantifiable data from imaging studies. We have developed a simple and adaptable workflow to extract quantitative data from fluorescence-based imaging studies using Drosophila models of neurodegeneration. Specifically, we describe an easy-to-follow, semi-automated approach using Fiji/ImageJ to analyze two cellular processes: first, we quantify protein aggregate content and profile in the Drosophila optic lobe using fluorescent-tagged mutant huntingtin proteins; and second, we assess autophagy-lysosome flux in the Drosophila visual system with ratiometric-based quantification of a tandem fluorescent reporter of autophagy. Importantly, the protocol outlined here includes a semi-automated segmentation step to ensure all fluorescent structures are analyzed to minimize selection bias and to increase resolution of subtle comparisons. This approach can be extended for the analysis of other cell biological structures and processes implicated in neurodegeneration, such as proteinaceous puncta (stress granules and synaptic complexes), as well as membrane-bound compartments (mitochondria and membrane trafficking vesicles). This method provides a standardized, yet adaptable reference point for image analysis and quantification, and could facilitate reliability and reproducibility across the field, and ultimately enhance mechanistic understanding of neurodegeneration.

Quantitative Cell Biology of Neurodegeneration in Drosophila Through Unbiased Analysis of Fluorescently Tagged Proteins Using ImageJ

We have developed a simple and adaptable workflow to extract quantitative data from fluorescence-imaging-based cell biological studies of protein aggregation and autophagic flux in the central nervous system of Drosophila models of neurodegeneration.

Ateş Drosophila ImageJ kullanarak Fluorescently Tagged proteinlerin tarafsız analizi ile yılında niceliksel hücre biyolojisi

With the rising prevalence of neurodegenerative diseases, it is increasingly important to understand the underlying pathophysiology that leads to neuronal ...

Nörobilim

Quantitative Analysis of Autophagy using Advanced 3D Fluorescence Microscopy

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, traditional chemotherapeutic approaches have been largely unsuccessful. Hormone therapy is effective at early stage, but often fails with the eventual development of hormone-refractory tumors. We have been interested in developing therapeutics targeting specific metabolic deficiency of tumor cells. We recently showed that prostate tumor cells specifically lack an enzyme (argininosuccinate synthase, or ASS) involved in the synthesis of the amino acid arginine1. This condition causes the tumor cells to become dependent on exogenous arginine, and they undergo metabolic stress when free arginine is depleted by arginine deiminase (ADI)1,10. Indeed, we have shown that human prostate cancer cells CWR22Rv1 are effectively killed by ADI with caspase-independent apoptosis and aggressive autophagy (or macroautophagy)1,2,3. Autophagy is an evolutionarily-conserved process that allows cells to metabolize unwanted proteins by lysosomal breakdown during nutritional starvation4,5. Although the essential components of this pathway are well-characterized6,7,8,9, many aspects of the molecular mechanism are still unclear - in particular, what is the role of autophagy in the death-response of prostate cancer cells after ADI treatment? In order to address this question, we required an experimental method to measure the level and extent of autophagic response in cells - and since there are no known molecular markers that can accurately track this process, we chose to develop an imaging-based approach, using quantitative 3D fluorescence microscopy11,12.
Using CWR22Rv1 cells specifically-labeled with fluorescent probes for autophagosomes and lysosomes, we show that 3D image stacks acquired with either widefield deconvolution microscopy (and later, with super-resolution, structured-illumination microscopy) can clearly capture the early stages of autophagy induction. With commercially available digital image analysis applications, we can readily obtain statistical information about autophagosome and lysosome number, size, distribution, and degree of colocalization from any imaged cell. This information allows us to precisely track the progress of autophagy in living cells and enables our continued investigation into the role of autophagy in cancer chemotherapy.

Autophagy is a ubiquitous process that enables cells to degrade and recycle proteins and organelles. We apply advanced fluorescence microscopy to visualize and quantify the small, but essential, physical changes associated with the induction of autophagy, including the formation and distribution of autophagosomes and lysosomes, and their fusion into autolysosomes.

Gelişmiş 3D Floresan Mikroskobu kullanılarak Otofaji Kantitatif Analiz

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, ...

Live Cell Imaging of Early Autophagy Events: Omegasomes and Beyond

Autophagy is a cellular response triggered by the lack of nutrients, especially the absence of amino acids. Autophagy is defined by the formation of double membrane structures, called autophagosomes, that sequester cytoplasm, long-lived proteins and protein aggregates, defective organelles, and even viruses or bacteria. Autophagosomes eventually fuse with lysosomes leading to bulk degradation of their content, with the produced nutrients being recycled back to the cytoplasm. Therefore, autophagy is crucial for cell homeostasis, and dysregulation of autophagy can lead to disease, most notably neurodegeneration, ageing and cancer.	
	Autophagosome formation is a very elaborate process, for which cells have allocated a specific group of proteins, called the core autophagy machinery. The core autophagy machinery is functionally complemented by additional proteins involved in diverse cellular processes, e.g. in membrane trafficking, in mitochondrial and lysosomal biology. Coordination of these proteins for the formation and degradation of autophagosomes constitutes the highly dynamic and sophisticated response of autophagy. Live cell imaging allows one to follow the molecular contribution of each autophagy-related protein down to the level of a single autophagosome formation event and in real time, therefore this technique offers a high temporal and spatial resolution.	
	Here we use a cell line stably expressing GFP-DFCP1, to establish a spatial and temporal context for our analysis. DFCP1 marks omegasomes, which are precursor structures leading to autophagosomes formation. A protein of interest (POI) can be marked with either a red or cyan fluorescent tag. Different organelles, like the ER, mitochondria and lysosomes, are all involved in different steps of autophagosome formation, and can be marked using a specific tracker dye. Time-lapse microscopy of autophagy in this experimental set up, allows information to be extracted about the fourth dimension, i.e. time. Hence we can follow the contribution of the POI to autophagy in space and time.

Time-lapse microscopy of fluorescently labeled autophagy markers allows monitoring of the dynamic autophagy response with high temporal resolution. Using specific autophagy and organelle markers in a combination of 3 different colors, we can follow the contribution of a protein to autophagosome formation in a robust spatial and temporal context.

Erken Otofaji Etkinlikler Hücre Görüntüleme Canlı: Omegasomes ve Ötesi

Autophagy is a  cellular response triggered by the lack of nutrients, especially the absence of  amino acids. Autophagy is defined by the formation of ...

Assessing Autophagic Flux by Measuring LC3, p62, and LAMP1 Co-localization Using Multispectral Imaging Flow Cytometry

Autophagy is a catabolic pathway in which normal or dysfunctional cellular components that accumulate during growth and differentiation are degraded via the lysosome and are recycled. During autophagy, cytoplasmic LC3 protein is lipidated and recruited to the autophagosomal membranes. The autophagosome then fuses with the lysosome to form the autolysosome, where the breakdown of the autophagosome vesicle and its contents occurs. The ubiquitin-associated protein p62, which binds to LC3, is also used to monitor autophagic flux. Cells undergoing autophagy should demonstrate the co-localization of p62, LC3, and lysosomal markers. Immunofluorescence microscopy has been used to visually identify LC3 puncta, p62, and/or lysosomes on a per-cell basis. However, an objective and statistically rigorous assessment can be difficult to obtain. To overcome these problems, multispectral imaging flow cytometry was used along with an analytical feature that compares the bright detail images from three autophagy markers (LC3, p62 and lysosomal LAMP1) and quantifies their co-localization, in combination with LC3 spot counting to measure autophagy in an objective, quantitative, and statistically robust manner.

Here, multispectral imaging flow cytometry with an analytical feature that compares bright detail images of 3 autophagy markers and quantifies their co-localization, along with LC3 spot counting, was used to measure autophagy in an objective, quantitative, and statistically robust manner.

Multifektral Görüntüleme Akış Sitometrisi Kullanılarak LC3, p62 ve LAMP1 Birlikte Lokalizasyonu Ölçülerek Otofajik Fluxın Değerlendirilmesi

Autophagy is a catabolic pathway in which normal or dysfunctional cellular components that accumulate during growth and differentiation are degraded via ...

Study of Protein-protein Interactions in Autophagy Research

Protein-protein interactions are important for understanding cellular signaling cascades and identifying novel pathway components and protein dynamics. The majority of cellular activities require physical interactions between proteins. To analyze and map these interactions, various experimental techniques as well as bioinformatics tools were developed. Autophagy is a cellular recycling mechanism that allows the cells to cope with different stressors, including nutrient deprivation, chemicals, and hypoxia. In order to better understand autophagy-related signaling events and to discover novel factors that regulate protein complexes in autophagy, we performed protein-protein interaction screens. Validation of these screening results requires the use of immunofluorescence and immunoprecipitation techniques. In this system, specific autophagy-related protein-protein interactions that we discovered were tested in Neuro2A (N2A) and HEK293T cell lines. Details of the technical procedures used are explained in this visualized experiment paper.

Presented here are two antibody-based protein-protein interaction research techniques: immunofluorescence and immunoprecipitation. These techniques are suitable for studying physical interactions between proteins for the discovery of novel components of cellular signaling pathways and for understanding protein dynamics.

Protein-protein etkileşimlerinin Autophagy araştırma çalışma

Protein-protein interactions are important for understanding cellular signaling cascades and identifying novel pathway components and protein dynamics. ...

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.

Floresans canlı hücre mikroskobu ile mitotik ve meiotic Fission Maya nükleer dinamiklerinin incelenmesi

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 ...

Application of Membrane and Cell Wall Selective Fluorescent Dyes for Live-Cell Imaging of Filamentous Fungi

The application of membrane and cell wall selective fluorescent dyes for live-cell imaging analyses of organelle dynamics in fungal cells started two decades ago and since then continues to contribute greatly to our understanding of the filamentous fungal lifestyle. This paper provides a practical guide for the utilization of the two membrane dyes FM 1-43 and FM 4-64 and the four cell wall stains Calcofluor White M2R, Solophenyl Flavine 7GFE 500, Pontamine Fast Scarlet 48 and Congo Red. The focus is on their low-dose application to ascertain artefact-free staining, their co-imaging properties, and their quantitative evaluation. The presented methods are applicable to all filamentous fungal samples that can be prepared in the described ways. The fundamental staining approaches can serve as starting points for adaptations to species that might require different cultivation conditions. First, biophysical and biochemical properties are reviewed as their understanding is essential for using these dyes as truly vital fluorescent stains. Secondly, step-by-step protocols are presented that detail the preparation of various fungal sample types for fluorescent live-cell imaging. Finally, example experiments illustrate different approaches to: (1) identify defects in the spatio-temporal organization of endocytosis in genetic mutants, (2) comparatively characterize shared and distinct co-localization of GFP-labeled target proteins in the endocytic pathway, (3) identify morphogenetic cell wall defects in a genetic mutant, and (4) monitor cell wall biogenesis in real time.

Vital fluorescent dyes are essential tools for live-cell imaging analyses in modern fungal cell biology. This paper details the application of established and lesser-known fluorescent dyes for tracking plasma membrane dynamics, endo-/exocytosis and cell wall morphogenesis in filamentous fungi.

Filamentöz Mantarların Canlı Hücre Görüntülemesi İçin Membran ve Hücre Duvarı Seçici Floresan Boyaların Uygulanması

The application of membrane and cell wall selective fluorescent dyes for live-cell imaging analyses of organelle dynamics in fungal cells started two ...

Analyzing Starvation-Induced Autophagy in the Drosophila melanogaster Larval Fat Body

Autophagy is a cellular self-digestion process. It delivers cargo to the lysosomes for degradation in response to various stresses, including starvation. The malfunction of autophagy is associated with aging and multiple human diseases. The autophagy machinery is highly conserved-from yeast to humans.&#160;The larval fat body of Drosophila melanogaster, an analog for vertebrate liver and adipose tissue, provides a unique model for monitoring autophagy in vivo. Autophagy can be easily induced by nutrient starvation in the larval fat body. Most autophagy-related genes are conserved in Drosophila. Many transgenic fly strains expressing tagged autophagy markers have been developed, which facilitates the monitoring of different steps in the autophagy process. The clonal analysis enables a close comparison of autophagy markers in cells with different genotypes in the same piece of tissue. The current protocol details procedures for (1) generating somatic clones in the larval fat body, (2) inducing autophagy via amino acid starvation, and (3) dissecting the larval fat body, aiming to create a model for analyzing differences in autophagy using an autophagosome marker (GFP-Atg8a) and clonal analysis.

Analyzing Starvation-Induced Autophagy in the Drosophila melanogaster Larval Fat Body

The present protocol describes the induction of autophagy in the Drosophila melanogaster larval fat body via nutrient depletion and analyzes changes in autophagy using transgenic fly strains.

Drosophila melanogaster larva yağ gövdesinde açlığa bağlı otofajinin analizi

Autophagy is a cellular self-digestion process. It delivers cargo to the lysosomes for degradation in response to various stresses, including starvation. ...

Otofaji Analiz

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