Biz mükemmel teknik destek için bir kollajen protokol ve Jutta Fey ve Ursula Hinz paylaşmak için Urmas Arumae teşekkür etmek istiyorum. Ayrıca biz nazik Video Atış için yardım için Hıristiyan F. Ackermann, Ulrike Engel ve Heidelberg Üniversitesi Nikon Görüntüleme Merkezi ve ayrıca Joachim Kirsch teşekkür etmek istiyorum. Çalışma kısmen Deutsche Forschungsgemeinschaft (SFB 592) yoluyla finanse edildi.

1. Kollajen Jeller hazırlanması <ol><li> 455 ul 10x MEM, 112 ul% 7.5 NaHCO3, 50 ul glutamin ve NaOH içeren bir stok ortamı hazırlayın. Konsantrasyon ve NaOH miktarı sıçan kuyruğu kolajeni hazırlanması (1.2), 1.000 ul olmak stok orta son hacmine bağlıdır. </li><li> Ebendal (1) &#39;e göre-fare kuyruk kolajeni hazırlayın. 4 ° C&#39;de depolayın Kolajen çözeltisi Kollajen çözümün bir bozulma gözlenmemektedir. Yeni bir toplu hazırlandıktan sonra, (1.1) stok ortam için gerekli olan NaOH konsantrasyonunun tahmin. NaOH miktarı ve konsantrasyon titrasyonu için ortamın pH gösterge kullanın. 800 ul asidik fare kuyruk kolajeni stok orta 210 ul karıştığında kırmızı bir gölge çevirmek zorunda. NaOH konsantrasyonunun çok düşük ise kolajen çözeltisi ortamın pH gösterge dolayı, sarı dönecektir. Eşya olmadan ortam ve karışım için kolajen eklemekabarcıklar ucing. Buz üzerinde bu adımları uygulayın. Polimerizasyon kolajen çözeltisi ve stok orta karıştırıldıktan sonra 2 saat içinde meydana gelir ve yeni çözelti 37 ° C de kuluçkaya bırakılır Bir deneme başlamadan önce bunu sınayın. 1.3) stok orta 210 ul (1.2) ile kollajen solüsyonu 800 ul karıştırın. 8 de kamara slayt kuyularda bu çözüm yeri 100 ul. 37 slaytlar inkübe ° C,% 5 CO2 ve bir hücre kültürü inkübatöründe nemli koşullar. Bir hücre kültür tezgah ve steril koşullar altında kolajen jellerin hazırlanması. Kollajen 2 saat içinde gelatinizes. </li></ol> 2. Embriyonik SCGs diseksiyonu <ol><li> Kez hamile rahim fareler (E16-18) ve daha fazla ihtiyaç kadar PBS saklayın Harvest embriyolar. </li><li> Amniyon itibaren bir embriyo teşrih. Klavikula düzeyinde kaudal embriyo başını kesmek. &quot;Böcek-iğne&quot; ile Silikon alt yemeğin üzerine başını düzelt. Başın ventral tarafında bir size karşı karşıya bulunmaktadırEğer submandibuler bölgede görmek olurdu. Fiksasyon daha kolay hazırlanmasını sağlar. </li><li> Sol ve sağ submandibular bölgedeki cilt çıkarın ve deri altı bağ dokusu ile. </li><li> Hyoid, infrahyoidal kas ve SKM kas üzerine görünümünü temizlemek için kendi konumdan submandibular tükrük bezleri çıkarın. </li><li> Gırtlak ve nefes borusu üzerine görünümünü temizlemek için dikkatle bu kaslar çıkarın. Trakea ve larinks çıkarın. Karotis arterler sonra prevertebral kaslar üzerinde her iki tarafta görülür. SCG karotid arterlerin çatallanma bulunan ve oval bir şekil vardır. Dikkatlice ganglionlar kaldırmak ve PBS koyun. Onları yapışmasını iseniz diseksiyon araçları yavaşça ganglionlarda çıkarın. Bu forseps hem de SCG çıkarılması için bir &quot;böcek iğne&quot; ile monte edilmiş bir iğne tutucuya kullanmak için faydalıdır. </li><li> Eğer enou parçalara kadar bir kez PBS içinde, PBS içinde oda sıcaklığında saklayın gangliyongh ganglionlarda. Sonra kan damarları ve bağ dokusundan ganglionlarda temizleyin. Bir laminer akış tezgah altına yerleştirilen bir diseksiyon mikroskobu altında SCG diseksiyonu ve temizlik yapın. </li><li> Son olarak, daha kolay kullanım için şırınga üzerine monte şırınga iğne yardımıyla jelatinize kollajen jeller üzerine eksplante ganglionlarda yerleştirin. </li><li> % 5 CO2 ile nemli koşullar ile, 37 ° C &#39;de bir hücre kültürü kuluçka makinesi içinde jelatinleştirilmiş kollajen SCG eksplantlar inkübe edin. </li></ol> 3. SCG Eksplantlarından Tedavisi <ol><li> 1-2 saat inkübasyondan sonra, B27 takviyesi, glutamin ve antibiyotik içeren 100 ul Neurobasal hücre kültür ortamı ile SCG eksplant içeren kollajen kapsamaktadır. Artık oda slaytların kuyular 200 ul (100 ul ve 100 ul jel orta) bir hacmi içerir. , Besiyerinin bir 200 ul ekle ancak şimdi akson büyümesini kolaylaştırmak için NGF (60 ng / ml) içeren. Buna uygun olarak, NGF, nihai konsantrasyon 30 ng / ml &#39;dir. </li><li><ol class="lalpha"><li> SC göç başlangıçlı araştırmak için, in vitro 0 (DIV0) gün doğrudan ek faktörler ekleyin. Gerekli olan çift konsantrasyonu (2) &#39;de NGF içeren medyumda faktörler çözülür. </li><li> Zaten aksonlar boyunca göç başladı SC&#39;ler, üzerindeki etkisini analiz etmek amacıyla, DIV4 (deney potansiyel durağı) kadar DIV3 ilave faktörler ekleyin. Bu amaçla, dikkatlice DIV3 de çözelti 180 ul kaldırmak ve 200 ul yeni ortamı içeren NGF ve çift konsantrasyonu (2) çıkar ve ek faktörler ekleyin. </li></ol></li></ol> 4. Time-lapse Görüntüleme Analizler için bir inverted mikroskop kullanın. Çeşitli amaçları görünümü ve büyütme alanını tanımlayarak, kullanılabilir. SCG eksplant görüntüleme cam slayt ve kollajen ile gerçekleştirilir olarak önemli bir yönü ise, ikinci amacı çalışma mesafesijel. 1/10-30 dakika kayıt kare hızı iyi sonuçlar (2) gösterdi. Bununla birlikte, bu görünüş bilimsel soruya ayarlanmak zorundadır. Normal bir CCD kamera ile görüntü elde etmek için de kullanılabilir. Zaman atlamalı görüntüleme için bir hücre kültürü inkübasyon odası mikroskop aşamasına bağlı olmak zorundadır. % 5 CO2 ile nemli koşullar ile, 37 ° C de görüntüleme sırasında doku inkübe edin. Görüntüleme başlamadan önce kuluçka sistemi bir saat başlatın. Bu odaya slayt dahil mikroskop parçaları (örneğin objektif) sıcaklığa ayarlamanızı sağlar ve sıcaklık kaynaklı sürüklenir önler. Mikroskop yazılım yardımı ve SCG eksplantlar farklı uygulanan koşulların eşzamanlı analizleri için bir yazılım kontrollü motorize aşaması (Çok pozisyonlu ayar) ile analizler belirli alanlarda (eksplant üzerinde olan ve farklı eksplant arasında) tanımlayın. Kullanılabilir hızlandırılmış görüntüleme yabani-tip doku hem de transjenik hayvanlardan elde edilen doku için(3): SC&#39;ler (GFP S100B) markalama. Görüntüleme floroforlar için bir floresan ışık kaynağı micropscope kurulum uygulanacak vardır. Standart filtreleri kullanın. 5. SC göç mesafeleri kantifikasyonu <ol><li> Son nokta (örneğin DIV4) az, 3-4 saat boyunca odasında slayt% 4 PFA ile kollajen jeller sabitleyin. Ardışık olarak PBS ile 10 dakika için kolajen jellerin 5 kez yıkayın. Immünsitokimya (2) için standart protokoller uygulayın. Eğer SCGs hazırlanması için yeni iseniz, tirozin hidroksilaz karşı immünohistokimyasal tarafından sempatik ganglion (TH) katekolaminerjik hücreler için ortak bir belirteç olarak ganglion kimliğini doğrulamak. Immünohistokimya sırasında (birincil antikor sonra), jeller yıkama için yararlı olan daha büyük bir hacimde sahip 24 gözlü levhalar için eksplant ihtiva eden kolajen jellerin aktarın. </li><li> Immünhistokimya sonra, cam slaytlar kollajen jel dikkatlice yerleştirin. DikkatliceKalan çözüm kaldırmak ve kollajen kurulayın / iki boyut için küçültmek sağlar. Bu mesafe (2) kolayca ölçümleri sağlar. Bundan sonra, örnekleri monte. </li><li> Nihayet, Fiji (NIH) yazılımı yardımıyla göç mesafeleri ölçmek. Hiçbir özel eklentileri bu amaçla ihtiyaç vardır. Um içinde doğru ölçümler sağlamak için, doğru görüntüleme metadata ve Fiji altındaki ayarları, görüntü ve ölçek kontrol edin. Hücrelerin ölçümü için de Fiji kullanın. </li></ol>

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L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescent+proteins+expressed+in+mouse+transgenic+lines+mark+subsets+of+glia,+neurons,+macrophages,+and+dendritic+cells+for+vital+examination.">Fluorescent proteins expressed in mouse transgenic lines mark subsets of glia, neurons, macrophages, and dendritic cells for vital examination.</a> The Journal of Neuroscience. 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R., Mirsky, R., Matsas, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+neuron-glia+signal+beta-neuregulin+promotes+Schwann+cell+motility+via+the+MAPK+pathway.">The neuron-glia signal beta-neuregulin promotes Schwann cell motility via the MAPK pathway.</a> Glia. 34 (1), 39-51 (2001).</li><li>Yamauchi, J., Miyamoto, Y., Chan, J. R., Tanoue, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ErbB2+directly+activates+the+exchange+factor+Dock7+to+promote+Schwann+cell+migration.">ErbB2 directly activates the exchange factor Dock7 to promote Schwann cell migration.</a> The Journal of cell biology. 181 (2), 351-365 (2008).</li><li>Anton, E. S., Weskamp, G., Reichardt, L. F., Matthew, W. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nerve+growth+factor+and+its+low-affinity+receptor+promote+Schwann+cell+migration.">Nerve growth factor and its low-affinity receptor promote Schwann cell migration.</a> Proceedings of the National Academy of Sciences of the United States of America. 91 (7), 2795-2799 (1994).</li><li>Mahanthappa, N. K., Anton, E. S., Matthew, W. 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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=Hyperglycaemia+inhibits+Schwann+cell+proliferation+and+migration+and+restricts+regeneration+of+axons+and+Schwann+cells+from+adult+murine+DRG.">Hyperglycaemia inhibits Schwann cell proliferation and migration and restricts regeneration of axons and Schwann cells from adult murine DRG.</a> Molecular and Cellular Neurosciences. 37 (2), 298-311 (2008).</li><li>Sakaue-Sawano, A., Kurokawa, H., Morimura, T., Hanyu, A., Hama, H., Osawa, H., Kashiwagi, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+spatiotemporal+dynamics+of+multicellular+cell-cycle+progression.">Visualizing spatiotemporal dynamics of multicellular cell-cycle progression.</a> Cell. 132 (3), 487-498 (2008).</li><li>Park, D., Don, A. S., Massamiri, T., Karwa, A., Warner, B., MacDonald, J., Hemenway, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+imaging+of+cell+death+using+an+Hsp90+ligand.">Noninvasive imaging of cell death using an Hsp90 ligand.</a> Journal of the American Chemical Society. 133 (9), 2832-2835 (2011).</li><li>Shcherbo, D., Souslova, E. A., Goedhart, J., Chepurnykh, T. V., Gaintzeva, A., Shemiakina, I. I., Gadella, T. W. J., Lukyanov, S., Chudakov, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Practical+and+reliable+FRET/FLIM+pair+of+fluorescent+proteins.">Practical and reliable FRET/FLIM pair of fluorescent proteins.</a> BMC Biotechnology. 9, 24 (2009).</li></ol>

Çıkar çatışması ilan etti.

Periferik sinir sisteminin gelişimi heyecan verici bir süreçtir. Gelişimi tamamlandıktan sonra, aksonların, insanlarda, sık sık, 100 cm olabilir tüm uzunluğu boyunca, SKS ile ensheathed edilir. Bu amaca yönelik olarak, gerekli SCs sayısı doğru gelişme sırasında oluşturulmalıdır ve SCs da tam kapsamı sağlamak aksonal için çevre uzanan akson boyunca hareket etmek zorunda. Bu miyelinli hem de için unmeylinated aksonlar için de geçerlidir. Her iki durumda da tüm aksonların SCs ile temas halinde ...

<table border="1"><tbody><tr><td> Reaktif / Malzeme Adı </td><td> Şirket </td><td> Katalog Numarası </td><td> Yorumlar </td></tr><tr><td> 10x MEM </td><td> Gibco </td><td> 21430 </td><td></td></tr><tr><td> Sodyum Bikarbonat (% 7.5) </td><td> Gibco </td><td> 25080 </td><td></td></tr><tr><td> Glutamin </td><td> Gibco </td><td> 25030 </td><td></td></tr><tr><td> NaOH </td><td> Merck </td><td> 109137 </td><td></td></tr><tr><td> NGF </td><td> Roche </td><td> 1058231 </td><td> ARGE # 556-NG-100 </td></tr><tr><td> Neurobasal Orta </td><td> Gibco </td><td> 21103 </td><td></td></tr><tr><td> B27 Supplement </td><td> Gibco </td><td> 17504 </td><td></td></tr><tr><td> antibiyotikler </td><td> Gibco </td><td> 15640 </td><td></td></tr><tr><td> d-PBS </td><td> Gibco </td><td> 14040 </td><td></td></tr><tr><td> Böcek iğneleri </td><td> FST </td><td> 26002-20 </td><td></td></tr><tr><td> şırınga iğnesi </td><td> Braun </td><td></td><td> BD # 300013 </td></tr><tr><td> 8 de kamara slayt </td><td> Lab tek </td><td> 177402 </td><td></td></tr></tbody></table>

analyzing murine schwann cell development along growing axons

Periferik sinirlerin gelişimi ilginç bir süreçtir. Nöronlar insanlarda 100&#39;den fazla cm uzaklıkta nöronun soma gelen genellikle belirli hedeflere, innerve aksonlar gönderir. Gelişme sırasında nöronal hayatta kalma hedef türevi büyüme faktörleri üzerinde değil, aynı zamanda Schwann hücreleri (SC&#39;ler) bir desteğe bağlıdır. Sinaps veya nöromuskuler kavşağa nöronal soma (veya merkezi periferik sinir sistemine geçiş) bölgesinden Bu amaçla SC ensheath aksonlar için. Schwann hücreleri nöral krest türevleri ve tüm akson SC&#39;ler ile kaplıdır kadar çıkan aksonlar boyunca habercileri olarak göç ederler. Bu periferik sinir sisteminin gelişimi için SC göçün önemini göstermektedir ve bu sürecin araştırılması gerekliliğini vurgulamaktadır. SC gelişme analiz etmek için, bir ayar da geçiş için onların fizyolojik alt tabaka, akson içeren SCs yanında olan ihtiyaç vardır. Intrauterin gelişme nedeniyle <em&gt; in vivo time-lapse görüntüleme, ancak, (Mus musculus) fare gibi plasental omurgalılarda mümkün değildir. Bunu aşmak için, biz üstün servikal ganglion (SCG) eksplant tekniği uyarlanmıştır. Sinir büyüme faktörü (NGF) ile tedavi üzerine SCG eksplantlar gangliyondan çevreye aksonları boyunca göç SC öncüleri takip aksonlar uzatmak. Bu sistemin güzelliği SC endojen SC bir havuz ve onlar aynı anda büyüyor kendi fizyolojik aksonlar boyunca göç ettiğini elde olmasıdır. Aksonlar boyunca SC gelişimi SC göç içgörüler kazanmak için başka imkanların açıldığı, time-lapse görüntüleme ile analiz edilebilir, çünkü bu sistem, özellikle şaşırtıcıdır.

Aksonal büyüme NGF (4) (film düzeni S1 Şekil 1 düzeni) ile muamele üzerine ikinci eksplantlar SCG kolaylaştırılır. Bu işlem herhangi bir inverted mikroskop ile görülebilen ve time-lapse görüntüleme (film S2) takip edilebilir. Bir bilim adamı fare embriyoları SCG diseksiyon için yeni ise şiddetle basit bir anti-tirozin hidroksilaz (TH) immünohistokimyasal olarak tekniğin bir doğrulama öneririz. TH etiketi aksonlar (Şekil 2B) katekolaminerjik nör...

Watch this Scientific Journal Video about Analyzing Murine Schwann Cell Development Along Growing Axons at JoVE.com

Analyzing Murine Schwann Cell Development Along Growing Axons

Burada SC&#39;ler uzanan aksonlar boyunca geliştirmek için mümkün olduğu bir Schwann hücresi (SC) göç tahlil tarif.

Büyüyen Aksonlar boyunca murin Schwann Hücresi Kalkınma Analizi

The  development of peripheral nerves is an intriguing process. Neurons send out  axons to innervate specific targets, which in humans are often more than ...

analyzing-murine-schwann-cell-development-along-growing-axons

Research

JoVE Journal

Neuroscience

11.6K Görüntüleme.  University of Freiburg. Burada SC'ler uzanan aksonlar boyunca geliştirmek için mümkün olduğu bir Schwann hücresi (SC) göç tahlil tarif.

Video: Analyzing Murine Schwann Cell Development Along Growing Axons

Live Imaging of Dorsal Root Axons after Rhizotomy

The primary sensory axons injured by spinal root injuries fail to regenerate into the spinal cord, leading to chronic pain and permanent sensory loss. Regeneration of dorsal root (DR) axons into spinal cord is prevented at the dorsal root entry zone (DREZ), the interface between the CNS and PNS. Our understanding of the molecular and cellular events that prevent regeneration at DREZ is incomplete, in part because complex changes associated with nerve injury have been deduced from postmortem analyses. Dynamic cellular processes, such as axon regeneration, are best studied with techniques that capture real-time events with multiple observations of each living animal. Our ability to monitor neurons serially in vivo has increased dramatically owing to revolutionary innovations in optics and mouse transgenics. Several lines of thy1-GFP transgenic mice, in which subsets of neurons are genetically labeled in distinct fluorescent colors, permit individual neurons to be imaged in vivo1. These mice have been used extensively for in vivo imaging of muscle2-4 and brain5-7, and have provided novel insights into physiological mechanisms that static analyses could not have resolved. Imaging studies of neurons in living spinal cord have only recently begun. Lichtman and his colleagues first demonstrated their feasibility by tracking injured dorsal column (DC) axons with wide-field microscopy8,9. Multi-photon in vivo imaging of deeply positioned DC axons, microglia and blood vessels has also been accomplished10. Over the last few years, we have pioneered in applying in vivo imaging to monitor regeneration of DR axons using wide-field microscopy and H line of thy1-YFP mice. These studies have led us to a novel hypothesis about why DR axons are prevented from regenerating within the spinal cord11.
In H line of thy1-YFP mice, distinct YFP+ axons are superficially positioned, which allows several axons to be monitored simultaneously. We have learned that DR axons arriving at DREZ are better imaged in lumbar than in cervical spinal cord. In the present report we describe several strategies that we have found useful to assure successful long-term and repeated imaging of regenerating DR axons. These include methods that eliminate repeated intubation and respiratory interruption, minimize surgery-associated stress and scar formation, and acquire stable images at high resolution without phototoxicity.

An in vivo imaging protocol to monitor primary sensory axons following dorsal root crush is described. The procedures utilize wide-field fluorescence microscopy and thy1-YFP transgenic mice, and permit repeated imaging of axon regeneration over 4 cm in the PNS and axon interactions with the interface of the CNS.

Rizotomi sonra Dorsal Kök Aksonlar Canlı Görüntüleme

The primary sensory axons injured by spinal root injuries fail to regenerate into the spinal cord, leading to chronic pain and permanent sensory loss. ...

Nörobilim

Single-cell Profiling of Developing and Mature Retinal Neurons

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and gene expression programs for extremely rare cell subsets has been a challenge using standard whole-tissue approaches. Gene expression profiling of individual cells allows for unprecedented access to cell types that comprise only a small percentage of the total tissue1-7. In addition, this technique can be used to examine the gene expression programs that are transiently expressed in small numbers of cells during dynamic developmental transitions8.
This issue of cellular diversity arises repeatedly in the central nervous system (CNS) where neuronal connections can occur between quite diverse cells9. The exact number of distinct cell types is not precisely known, but it has been estimated that there may be as many as 1000 different types in the cortex itself10. The function(s) of complex neural circuits may rely on some of the rare neuronal types and the genes they express. By identifying new markers and helping to molecularly classify different neurons, the single-cell approach is particularly useful in the analysis of cell types in the nervous system. It may also help to elucidate mechanisms of neural development by identifying differentially expressed genes and gene pathways during early stages of neuronal progenitor development.
As a simple, easily accessed tissue with considerable neuronal diversity, the vertebrate retina is an excellent model system for studying the processes of cellular development, neuronal differentiation and neuronal diversification. However, as in other parts of the CNS, this cellular diversity can present a problem for determining the genetic pathways that drive retinal progenitors to adopt a specific cell fate, especially given that rod photoreceptors make up the majority of the total retinal cell population11. Here we report a method for the identification of the transcripts expressed in single retinal cells (Figure 1). The single-cell profiling technique allows for the assessment of the amount of heterogeneity present within different cellular populations of the retina2,4,5,12. In addition, this method has revealed a host of new candidate genes that may play role(s) in the cell fate decision-making processes that occur in subsets of retinal progenitor cells8. With some simple adjustments to the protocol, this technique can be utilized for many different tissues and cell types.

A method for the isolation of single retinal cells and subsequent amplification of their cDNAs is described. Single-cell transcriptomics reveals the degree of cellular heterogeneity present in a tissue and uncovers new marker genes for rare cell populations. The accompanying protocol can be adjusted to suit many different cell types.

Gelişen ve Olgun Retina Nöronlar Tek hücreli Profilleme

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and ...

Isolation and Culture of Neural Crest Cells from Embryonic Murine Neural Tube

The embryonic neural crest (NC) is a multipotent progenitor population that originates at the dorsal aspect of the neural tube, undergoes an epithelial to mesenchymal transition (EMT) and migrates throughout the embryo, giving rise to diverse cell types 1-3. NC also has the unique ability to influence the differentiation and maturation of target organs4-6. When explanted in vitro, NC progenitors undergo self-renewal, migrate and differentiate into a variety of tissue types including neurons, glia, smooth muscle cells, cartilage and bone. 
NC multipotency was first described from explants of the avian neural tube7-9. In vitro isolation of NC cells facilitates the study of NC dynamics including proliferation, migration, and multipotency. Further work in the avian and rat systems demonstrated that explanted NC cells retain their NC potential when transplanted back into the embryo10-13. Because these inherent cellular properties are preserved in explanted NC progenitors, the neural tube explant assay provides an attractive option for studying the NC in vitro. 
To attain a better understanding of the mammalian NC, many methods have been employed to isolate NC populations. NC-derived progenitors can be cultured from post-migratory locations in both the embryo and adult to study the dynamics of post-migratory NC progenitors11,14-20, however isolation of NC progenitors as they emigrate from the neural tube provides optimal preservation of NC cell potential and migratory properties13,21,22. Some protocols employ fluorescence activated cell sorting (FACS) to isolate a NC population enriched for particular progenitors11,13,14,17. However, when starting with early stage embryos, cell numbers adequate for analyses are difficult to obtain with FACS, complicating the isolation of early NC populations from individual embryos. Here, we describe an approach that does not rely on FACS and results in an approximately 96% pure NC population based on a Wnt1-Cre activated lineage reporter23. 
The method presented here is adapted from protocols optimized for the culture of rat NC11,13. The advantages of this protocol compared to previous methods are that 1) the cells are not grown on a feeder layer, 2) FACS is not required to obtain a relatively pure NC population, 3) premigratory NC cells are isolated and 4) results are easily quantified. Furthermore, this protocol can be used for isolation of NC from any mutant mouse model, facilitating the study of NC characteristics with different genetic manipulations. The limitation of this approach is that the NC is removed from the context of the embryo, which is known to influence the survival, migration and differentiation of the NC2,24-28.

Isolation of embryonic neural crest from the neural tube facilitates the use of in vitro methods for studying migration, self-renewal, and multipotency of neural crest.

Embriyonik Mürin Nöral Tüp çıkan sinirsel Crest Hücre İzolasyonu ve Kültür

The embryonic neural crest (NC) is a multipotent progenitor population that originates at the dorsal aspect of the neural tube, undergoes an epithelial to ...

A Quantitative Cell Migration Assay for Murine Enteric Neural Progenitors

Neural crest cells (NCC) are a transient and multipotent cell population that originates from the dorsal neural tube and migrates extensively throughout the developing vertebrate embryo. In addition to providing peripheral glia and neurons, NCC generate melanocytes as well as most of the cranio-facial skeleton. NCC migration and differentiation is controlled by a combination of their axial origin along the neural tube and their exposure to regionally distinct extracellular cues. Such contribution of extracellular ligands is especially evident during the formation of the enteric nervous system (ENS), a complex interconnected network of neural ganglia that locally controls (among other things) gut muscle movement and intestinal motility. Most of the ENS is derived from a small initial pool of NCC that undertake a long journey in order to colonize - in a rostral to caudal fashion - the entire length of the prospective gut. Among several signaling pathways known to influence enteric NCC colonization, GDNF/RET signaling is recognized as the most important. Indeed, spatiotemporally controlled secretion of the RET ligand GDNF by the gut mesenchyme is chiefly responsible for the attraction and guidance of RET-expressing enteric NCC to and within the embryonic gut. Here, we describe an ex vivo cell migration assay, making use of a transgenic mouse line possessing fluorescently labeled NCC, which allows precise quantification of enteric NCC migration potential in the presence of various growth factors, including GDNF.

We present an ex vivo cell migration assay that allows precise quantification of enteric neural crest cell migration potential in the presence of various growth factors.

Kemirgen Enterik Sinir progenitörlerin için Kantitatif Hücre Göç Tahlili

Neural crest cells (NCC) are a transient and multipotent cell population that originates from the dorsal neural tube and migrates extensively throughout ...

Laser Nanosurgery of Cerebellar Axons In Vivo

Only a few neuronal populations in the central nervous system (CNS) of adult mammals show local regrowth upon dissection of their axon. In order to understand the mechanism that promotes neuronal regeneration, an in-depth analysis of the neuronal types that can remodel after injury is needed. Several studies showed that damaged climbing fibers are capable of regrowing also in adult animals1,2. The investigation of the time-lapse dynamics of degeneration and regeneration of these axons within their complex environment can be performed by time-lapse two-photon fluorescence (TPF) imaging in vivo3,4. This technique is here combined with laser surgery, which proved to be a highly selective tool to disrupt fluorescent structures in the intact mouse cortex5-9.
This protocol describes how to perform TPF time-lapse imaging and laser nanosurgery of single axonal branches in the cerebellum in vivo. Olivocerebellar neurons are labeled by anterograde tracing with a dextran-conjugated dye and then monitored by TPF imaging through a cranial window. The terminal portion of their axons are then dissected by irradiation with a Ti:Sapphire laser at high power. The degeneration and potential regrowth of the damaged neuron are monitored by TPF in vivo imaging during the days following the injury.

Laser Nanosurgery of Cerebellar Axons In Vivo

Two-photon imaging, coupled to laser nanodissection, are useful tools to study degenerative and regenerative processes in the central nervous system with subcellular resolution. This protocol shows how to label, image, and dissect single climbing fibers in the cerebellar cortex in vivo.

Serebellar Aksonlar Lazer Nanosurgery<em&gt; In Vivo</em

Only a few neuronal populations in the central nervous system (CNS) of adult mammals show local regrowth upon dissection of their axon. In order to ...

Live Imaging of Nicotine Induced Calcium Signaling and Neurotransmitter Release Along Ventral Hippocampal Axons

Sustained enhancement of axonal signaling and increased neurotransmitter release by the activation of pre-synaptic nicotinic acetylcholine receptors (nAChRs) is an important mechanism for neuromodulation by acetylcholine (ACh). The difficulty with access to probing the signaling mechanisms within intact axons and at nerve terminals both in vitro and in vivo has limited progress in the study of the pre-synaptic components of synaptic plasticity. Here we introduce a gene-chimeric preparation of ventral hippocampal (vHipp)&#8211;accumbens (nAcc) circuit in vitro that allows direct live imaging to analyze both the pre- and post-synaptic components of transmission while selectively varying the genetic profile of the pre- vs post-synaptic neurons. We demonstrate that projections from vHipp microslices, as pre-synaptic axonal input, form multiple, reliable glutamatergic synapses with post-synaptic targets, the dispersed neurons from nAcc. The pre-synaptic localization of various subtypes of nAChRs are detected and the pre-synaptic nicotinic signaling mediated synaptic transmission are monitored by concurrent electrophysiological recording and live cell imaging. This preparation also provides an informative approach to study the pre- and post-synaptic mechanisms of glutamatergic synaptic plasticity in vitro.

We developed a gene-chimeric preparation of ventral hippocampal &#8211; accumbens circuit in vitro that allows direct live imaging to analyze presynaptic mechanisms of nicotinic acetylcholine receptors (nAChRs) mediated synaptic transmission. This preparation also provides an informative approach to study the pre- and post-synaptic mechanisms of synaptic plasticity.

Nikotin Kaynaklı Kalsiyum Sinyali ve ventral Hipokampal Aksonlar boyunca Nörotransmitter Release Canlı Görüntüleme

Sustained enhancement of axonal signaling and increased neurotransmitter release by the activation of pre-synaptic nicotinic acetylcholine receptors ...

In Vivo Gene Transfer to Schwann Cells in the Rodent Sciatic Nerve by Electroporation

The formation of the myelin sheath by Schwann cells (SCs) is essential for rapid conduction of nerve impulses along axons in the peripheral nervous system. SC-selective genetic manipulation in living animals is a powerful technique for studying the molecular and cellular mechanisms of SC myelination and demyelination in vivo. While knockout/knockin and transgenic mice are powerful tools for studying SC biology, these methods are costly and time consuming. Viral vector-mediated transgene introduction into the sciatic nerve is a simpler and less laborious method. However, viral methods have limitations, such as toxicity, transgene size constraints, and infectivity restricted to certain developmental stages. Here, we describe a new method that allows selective transfection of myelinating SCs in the rodent sciatic nerve using electroporation. By applying electric pulses to the sciatic nerve at the site of plasmid DNA injection, genes of interest can be easily silenced or overexpressed in SCs in both neonatal and more mature animals. Furthermore, this in vivo electroporation method allows for highly efficient simultaneous expression of multiple transgenes. Our novel technique should enable researchers to efficiently manipulate SC gene expression, and facilitate studies on SC development and function.

In Vivo Gene Transfer to Schwann Cells in the Rodent Sciatic Nerve by Electroporation

Here, we present an in vivo technique for gene transfer to Schwann cells (SCs) in the rodent sciatic nerve. This simple technique is useful for investigating signaling mechanisms involved in the development and maintenance of myelinating SCs.

Elektroporasyon tarafından Kemirgen Siyatik Sinir Schwann Hücreleri için Vivo Gen Transferi

The formation of the myelin sheath by Schwann cells (SCs) is essential for rapid conduction of nerve impulses along axons in the peripheral nervous ...

Using Linear Agarose Channels to Study Drosophila Larval Crawling Behavior

Drosophila larval crawling is emerging as a powerful model to study neural control of sensorimotor behavior. However, larval crawling behavior on flat open surfaces is complex,&#160;including: pausing, turning, and meandering. This complexity in the repertoire of movement hinders detailed analysis of the events occurring during a single crawl stride cycle. To overcome this obstacle, linear agarose channels were made that constrain larval behavior to straight, sustained, rhythmic crawling. In principle, because agarose channels and the Drosophila larval body are both optically clear, the movement of larval structures labeled by genetically-encoded fluorescent probes can be monitored in intact, freely-moving larvae. In the past, larvae were placed in linear channels and crawling at the level of whole organism, segment, and muscle were analyzed1. In the future, larvae crawling in channels can be used for calcium imaging to monitor neuronal activity. Moreover, these methods can be used with larvae of any genotype and with any researcher-designed channel. Thus the protocol presented below is widely applicable for studies using the Drosophila larva as a model to understand motor control.

Using Linear Agarose Channels to Study Drosophila Larval Crawling Behavior

The Drosophila larva is a powerful model system to study neural control of behavior. This publication describes the use of linear agarose channels to elicit sustained bouts of linear crawling and methods to quantify the dynamics of larval structures during repetitive crawling behavior.

Doğrusal Agaroz Kanallar kullanarak Okuyacak<em&gt; Drosophila</em&gt; Larva Tarama Davranış

Drosophila larval crawling is emerging as a powerful model to study neural control of sensorimotor behavior. However, larval crawling behavior on flat ...

Analyzing Dendritic Morphology in Columns and Layers

In many regions of the central nervous systems, such as the fly optic lobes and the vertebrate cortex, synaptic circuits are organized in layers and columns to facilitate brain wiring during development and information processing in developed animals. Postsynaptic neurons elaborate dendrites in type-specific patterns in specific layers to synapse with appropriate presynaptic terminals. The fly medulla neuropil is composed of 10 layers and about 750 columns; each column is innervated by dendrites of over 38 types of medulla neurons, which match with the axonal terminals of some 7 types of afferents in a type-specific fashion. This report details the procedures to image and analyze dendrites of medulla neurons. The workflow includes three sections: (i) the dual-view imaging section combines two confocal image stacks collected at orthogonal orientations into a high-resolution 3D image of dendrites; (ii) the dendrite tracing and registration section traces dendritic arbors in 3D and registers dendritic traces to the reference column array; (iii) the dendritic analysis section analyzes dendritic patterns with respect to columns and layers, including layer-specific termination and planar projection direction of dendritic arbors, and derives estimates of dendritic branching and termination frequencies. The protocols utilize custom plugins built on the open-source MIPAV (Medical Imaging Processing, Analysis, and Visualization) platform and custom toolboxes in the matrix laboratory language. Together, these protocols provide a complete workflow to analyze the dendritic routing of Drosophila medulla neurons in layers and columns, to identify cell types, and to determine defects in mutants.

Here, we show how to analyze dendritic routing of Drosophila medulla neurons in columns and layers. The workflow includes a dual-view imaging technique to improve the image quality and computational tools for tracing, registering dendritic arbors to the reference column array and for analyzing the dendritic structures in 3D space.

Sütunlar ve Katmanlar dendritik Morfoloji Analizi

In many regions of the central nervous systems, such as the fly optic lobes and the vertebrate cortex, synaptic circuits are organized in layers and ...

Spectral Reflectometric Microscopy on Myelinated Axons In Situ

In a mammalian nervous system, myelin provides an electrical insulation by enwrapping the axon fibers in a multilayered spiral. Inspired by its highly-organized subcellular architecture, we recently developed a new imaging modality, named spectral reflectometry (SpeRe), which enables unprecedented label-free nanoscale imaging of the live myelinated axons in situ. The underlying principle is to obtain nanostructural information by analyzing the reflectance spectrum of the multilayered subcellular structure. In this article, we describe a detailed step-by-step protocol for performing a basic SpeRe imaging of the nervous tissues using a commercial confocal microscopic system, equipped with a white-light laser and a tunable filter. We cover the procedures of sample preparation, acquisition of spectral data, and image processing for obtaining nanostructural information.

Spectral Reflectometric Microscopy on Myelinated Axons In Situ

Here, we present a step-by-step protocol for imaging myelinated axons in a fixed brain slice using a label-free nanoscale imaging technique based on spectral reflectometry.