Bu çalışma RIKEN Beyin Bilimi Enstitüsü (BSI), İnsan Frontier Bilim Programı (HFSP) (TS verilen) ve RIKEN Junior Araştırma İşbirliği Programı (JRA), MK verilen RIKEN Beyin Bilimi Enstitüsü (BSI), İnsan Frontier Lisans Programı tarafından finanse edildi (HFSP) (TS ödüllendirildi) ve RIKEN Seyirci Araştırma İşbirliği Programı (JRA, MK verilen) bu işi finanse.

1. Kapiller ve DNA çözüm enjeksiyon için hazırlanması <ol><li> Maxi-Hazırlık veya dengi yöntemi plazmid DNA arındırın ve 2-3 mg / ml bir final konsantrasyon. Kısım 100 mikrogram, DNA hızlı yeşil boya (% 1 hisse senedi) ve TE 10μl (10mM Tris Üssü, 1mm EDTA Çözüm, pH 8.0) ve enjeksiyon karışımı için son DNA konsantrasyonu 1μg / ul 100 ses seviyesini ayarlamak ul. Plazmid DNA konsantrasyonu değiştirilebilir tek tek test edilmesi gerekir transfeksiyon verimliliği, plazmid boyutu bağlıdır ve. </li><li> 14.000 RPM hızında oda sıcaklığında 5 dakika boyunca DNA çözüm Spin ve herhangi bir kalıntı kaldırmak için supernatant toplamak. </li><li> Mikropipet çektirmenin kullanarak bir cam kapiller tubea cam kapiller tüplerin çekin. Ucu 20-30 mikron çapında yapmak için forseps ile ucu kapalı Pinch. Ucundan 800 mm-1 mm ölçün ve dış çapı 60 mikron (Şekil 1A) daha az olup olmadığını kontrol edin. </li><li> Mikromanipülatör kılcal bağlayın ve madeni yağ ile doldurun. DNA çözüm, çözüm içine daldırın ucu kapiller doldurmak ve DNA çözüm emmek için. </li></ol> 2. Platin elektrot Kaynaş Burada beyin korteks (Şekil 1F) gibi yüzeysel bölge içine electroporate sopa platin elektrotlar (Nepe gen, CUY611P2-1) kullanılır. 3. Mikro elektrotlar hazırlanması Beyin (yani, talamus ve hipotalamus) (Şekil 2B-E) derin bölüme electroporated için mikro elektrotlar kullanın. <ol><li> Bir tungsten sonunda (negatif elektrot) ve platin (pozitif elektrot) teller, altın kaplama pinler sarılmış ve parafilm ile sabittir. Bir pamuklu çubukla kök tel takın ve parafilm (Şekil 1B) ile her iki ucunda sarın. </li><li> 20-30 mikron 800 dış çapı 60 mikron mikron 1 mm ucu (Şekil 1C ve D) ulaşıncaya kadar eşit bir şekilde zımpara kağıdı ile telin ucu keskinleştirmek. </li><li> Yalıtımı için tel oje ince bir kat uygulayın. Oje kuruduktan sonra, ucu (uç kısmından yaklaşık 200 mikron) çıkarmak için aseton batırılmış bir pamuklu bir bez kullanın. Önemli not: farenin rahmine zarar görmesini önlemek için, 800 içinde kısmı mm-1 mm uç çapı 70 mm daha fazla (Şekil 1E) olmalıdır. </li></ol> 4. Ameliyat hazırlanması <ol><li> Hamile bir fare (E9.5-E15.5) anestezisi. Biz ilaç sınıf sodyum pentobarbital anesthetization göstermektedir (Tablo II; gram vücut ağırlığı başına 50 mikrogram, intraperitoneal olarak enjekte edilir ve 5 dakika bekleyin). Bir anestezik olarak pentobarbital sodyum Alternatifler Ketamin / Xylazine enjeksiyon veya gaz anestezikler (gaz kısa süreli işlemleri için tercih edilir). Enjeksiyon herhangi bir organ önlemek için dikkat ile yapılmalıdır, aksi takdirde rahmin zarar veya hayvanı öldürmek için neden olacaktır. Başarılı IP yapıldığında, hayatta kalma oranı% 95 daha fazla. Ayrıca cerrahi, açık hava ortamında yapılabilmektedir. Önce anestezik onaylamak için parmak pinching hayvan tarafından tepki olmaması için çalışma, test başladı. </li><li> Bir jilet ve% 50 EtOH kullanarak karın saç tıraş. Alternatif scrubs betadin ve alkol (% 70) ile cildi hazırlayın. </li><li> Ince makas ile karın orta hat kesi olun ve tüm rahim boynuzları 37 üzerine dikkatlice dışarı çekin ° C önceden ısıtılmış fosfat tamponlu salin (PBS) nemlendirilmiş pamuk gazlı bez, yara etrafına yerleştirilir. PBS zaman rahim nemli tutun. </li><li> Parmağı ve orta parmak arasında esnek bir fiber optik kablo tutun ve uterin boynuz altına koyun. Kullanmadan önce% 70 EtOH ile temizleyin kablo. Hiçbir mikroskop ya da büyüteç görünüm için gereklidir. Pozisyon fiber optik ışık optik kablo ve başparmak arasında rahim ve rahim duvarına yakın embriyo yukarı itmek için yavaşça sıkın. </li></ol> 5. DNA ve elektroporasyon Enjeksiyon <ol><li> Embriyo yerleştirilmiş, cam hedef ventrikül içine dikkatlice kılcal ve yaklaşık 1 ul DNA çözüm (Şekil 2A) enjekte yerleştirin. </li><li> Electoporation için sopa platin elektrotları ile brainIf yüzeysel bir parçası elektroporasyon için rahim dışında elektrotlar ve üreticinin talimatlarına göre (Tablo I) önerilen kare dalga akım darbeleri uygulayın. Beynin derin kısmında usingFor elektroporasyon, nmicro elektroporasyon, eedle tipi elektrotlar iseniz. Iinsert DNA&#39;sına ince bir tungsten negatif elektrot önerilen kare dalga akım darbeleri (Tablo I) (Şekil 2B) uygulamak sonra, iki elektrot arasındaki yeri ve hedef bölge rahim içine enjekte ventrikül ve platin elektrot. </li></ol> 6. Mesaj elektroporasyon <ol><li> Onun orig uterin horn yerine geriİnal konumu ve 37 ° C önceden ısıtılmış PBS 500 mcL ekleyin. </li><li> 9 mm autoclipauto klip ile cerrahi dikiş ve yakın dış tabaka ile iç tabaka dikin. </li><li> 2 saatlik bir ısıtma yastığı yerleştirin hayvanlar anestezi kurtarma izin vermek. Carprofen veya buprenorfin gibi Analjezikler, ameliyat sonrası ağrı için verilebilir. </li></ol> 7. Temsilcisi sonuçları: PCAG-EYFP kortikal elektroporasyon bazı örnekler, farklı zaman noktalarında sopa platin elektrot kullanılarak inşa şekil Şekil 32 de gösterilmiştir. Brain E13.5, E14.5, E15.5 electroporated ve postnatal gün (P) 6 hasat edilir. Ortaya çıkan ntibody boyama RORC &#39;ün 4. katmandaki ve EYFP transfekte hücreleri konumunu konumu GFP antikor boyama ile ortaya ortaya çıkarır ve her iki görüntüler dayatılan süper (Şekil 3A ve B) . Etiketli kortikal hücreler, zaman-bağımlı elektroporasyon kortikal tabaka özel GOF / LOF mümkün kılar (Şekil 32), her bir deney electroporated kortikal hücreler katmanı açıkça farklıdır. Hücre transfeksiyon embriyolar ve verimlilik canlılığı, embriyonun yaşına ve elektroporasyon yerini bağlı olarak değişir. Örnekler Tablo 1&#39;de listelenmiştir, ancak, koşullar sahne ve beynin bir parçası olarak her elektroporasyon için optimize edilmiş olmalıdır. Sopa platin elektrotları ile talamus ve hipotalamus gibi derin bir doku içine Elektroporasyon genelde düşük verimlilik (Tablo 1) verir. Beynin derin bölgelerine ulaşacak whichelectrodes, mikro elektrotlar kullanarak bu sorun çözülebilir. Şekil 3, gelişmekte olan diensefalon pCAG EYFP elektroporasyon 4 gösterileri örnek. Plazmid DNA çözüm E11.5 3. ventrikül içine enjekte edilir ve mikro elektroporasyon (Şekil 3C4C) tarafından takip edilmektedir. Electroporated alan talamus sınırlıdır korteks (Şekil 3B4B) aksonlar proje. Korteks tabakası 4 Akson, projeksiyon, aynı zamanda tüm nöron fillesfills EYFP tarafından görüntülenmiştir. (Şekil 3A4A). <img src="/files/ftp_upload/3024/3024fig1.jpg" alt="Şekil 1"/> Şekil 1 Cartoon kılcal doğru şekli gösteren şematik. (A) cam kapiller tüp, belli bir şekli yapmak için bir mikropipet çektirmesi ile çekilir. Bir ucu 20-30 mikron yapmak için forseps sıkışmak kapalı. Ucu (kırmızı dirsek) 800 mm-1mm ölçün ve dış çapı 60 mikron (yeşil dirsek) daha az olduğundan emin olun. (B), tungsten veya platin tel Bir ucu altın kaplama pimlerin üzerine sarılmış ve parafilm ile sabittir. Daha sonra ucu 1 mm den 20-30 mikron dış çap ve 60 mm olmak için bahşiş yapmak için zımpara kağıdı kullanın. (C) Görüntü tungsten tel şekillendirme önce. (D), tungsten tel şekillendirme sonra Image. (E), ince bir kat oje uygulandıktan sonra tungsten tel Resim. E Ölçekli bar CE için 10 mikron (küçük ölçekli). (F) Stick platin elektrot (Nepa gen. CUY611P2-1). F Ölçekli bar, 2 mm. <img src="/files/ftp_upload/3024/3024fig2.jpg" alt="Şekil 2"/> Şekil 2 cerrahi işlemin Karikatür şema. (A), lateral ventrikül veya büyük embriyolar (sol taraf) içine ve 3. ventrikül veya küçük embriyolar (sağ tarafı) içine enjeksiyon Diyagramı . (B) platin çubuk elektrot (sol taraf) ve iğne tipi elektrot (sağ tarafı) tarafından electrporation Diyagramı. <img src="/files/ftp_upload/3024/3024fig3.jpg" alt="Şekil 3"/> Şekil 3 fare telencephalon geliştirilmesi E13.5 (A) E14.5 (B) ve E15.5 (C) pCAG-EYFP electroporated ve P6 hasat edildi. Brain ayrı koronal kesitli ve GFP antikor veya RORC &#39;ün antikor ile boyandı ve görüntüler birleştirilir. (A) E13.5 transfect birçok katman 4 nöronlar pCAG-EYFP plazmid Elektroporasyon. 4 belirteçlerinin RORC &#39;ün tabakası ile örtüşmektedir. Katman 4 nöronlar daha yüzeysel E14.5 transfect hücreler, (B) pCAG-EYFP plazmid Elektroporasyon. (C) E15.5 layer 2 / 3 gibi elektroporasyon etiket birçok yüzeysel nöronlar. Ölçek çubuğu 200 mm. <img src="/files/ftp_upload/3024/3024fig4.jpg" alt="Şekil 4"/> Şekil 4 talamo-kortikal aksonlar (TCA) içine EYFP Transfeksiyon. (A) kortikal 4. katmandaki TCA terminus GFP antikor boyama ile ortaya çıkar. RORC &#39;ün antikor boyama, 4 katmanlı bir pozisyon ortaya çıkarmak için kullanılır. Her iki görüntü aynı bölümde alınan ve birleştirilir. (B) talamus içine elektroporasyon konumu ifade talamus 11 sınırlıdır GFP antikor boyama ve RORC &#39;ün boyama, aynı zamanda gösterilir. (C) talamik elektroporasyon ve TCA projeksiyon Karikatür şematik gösterilmiştir. Ölçek çubuğu 200 mm.

<ol>
	<li>Tabata, H., Nakajima, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+in+utero+gene+transfer+system+to+the+developing+mouse+brain+using+electroporation:+Visualization+of+neuronal+migration+in+the+developing+cortex.">Efficient in utero gene transfer system to the developing mouse brain using electroporation: Visualization of neuronal migration in the developing cortex.</a> Neuroscience. 103, 865-872 (2001).</li><li>Saito, T., Nakatsuji, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+gene+transfer+into+the+embryonic+mouse+brain+using+in+vivo+electroporation.">Efficient gene transfer into the embryonic mouse brain using in vivo electroporation.</a> Developmental Biology. 240, 237-246 (2001).</li><li>Fukuchi-Shimogori, T., Grove, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neocortex+patterning+by+the+secreted+signaling+molecule+FGF8.">Neocortex patterning by the secreted signaling molecule FGF8.</a> Science. 294, 1071-1074 (2001).</li><li>Kataoka, A., Shimogori, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fgf8+controls+regional+identity+in+the+developing+thalamus.">Fgf8 controls regional identity in the developing thalamus.</a> Development. 135, 2873-2881 (2008).</li><li>Imayoshi, I., Shimogori, T., Ohtsuka, T., Kageyama, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hes+genes+and+neurogenin+regulate+non-neural+versus+neural+fate+specification+in+the+dorsal+telencephalic+midline.">Hes genes and neurogenin regulate non-neural versus neural fate specification in the dorsal telencephalic midline.</a> Development. 135, 2531-2541 (2008).</li><li>Shimogori, T., Banuchi, V., Ng, H. Y., Strauss, J. B., Grove, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+signaling+centers+expressing+BMP,+WNT+and+FGF+proteins+interact+to+pattern+the+cerebral+cortex.">Embryonic signaling centers expressing BMP, WNT and FGF proteins interact to pattern the cerebral cortex.</a> Development. 131, 5639-5647 (2004).</li><li>Shimogori, T., Ogawa, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+application+with+in+utero+electroporation+in+mouse+embryonic+brain.">Gene application with in utero electroporation in mouse embryonic brain.</a> Development Growth &#38; Differentiation. 50, 499-506 (2008).</li><li>Takahashi, Y., Watanabe, T., Nakagawa, S., Kawakami, K., Sato, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Avian+Embryology.">Avian Embryology.</a> Methods in Cell Biology. Vol 87, 271-271 (2008).</li><li>Feil, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ligand-activated+site-specific+recombination+in+mice.">Ligand-activated site-specific recombination in mice.</a> Proceedings of the National Academy of Sciences of the United States of America. 93, 10887-10890 (1996).</li><li>Indra, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temporally-controlled+site-specific+mutagenesis+in+the+basal+layer+of+the+epidermis:+comparison+of+the+recombinase+activity+of+the+tamoxifen-inducible+Cre-ERT+and+Cre-ERT2+recombinases.">Temporally-controlled site-specific mutagenesis in the basal layer of the epidermis: comparison of the recombinase activity of the tamoxifen-inducible Cre-ERT and Cre-ERT2 recombinases.</a> Nucleic Acids Research. 27, 4324-4327 (1999).</li><li>Nakagawa, Y., O'Leary, D. 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=Dynamic+patterned+expression+of+orphan+nuclear+receptor+genes+ROR+alpha+and+ROR+beta+in+developing+mouse+forebrain.">Dynamic patterned expression of orphan nuclear receptor genes ROR alpha and ROR beta in developing mouse forebrain.</a> Developmental Neuroscience. 25, 234-244 (2003).</li></ol>

Çıkar çatışması ilan etti.

Bu protokol, biz sadece, farklı şeklinde elektrotlar kullanarak küçük bir embriyonik beyin kısıtlı alana pCAG EYFP transfeksiyon tekniği yararları nitelendirdi. Transfeksiyon verimlilik karşılaştırması farklı organizatörü tarafından daha önce açıklandığı için, hücre tipi özgüllüğü 1 gösterir. Ancak, sadece geçici ve plazmid bağlıdır değişir transfeksiyon gibi tekniği, sınırlamalar vardır, herhangi bir hücreyi özgüllüğü sahip değildir ve transfekte hücrelerinin sayısını kontrol altında tutmak zordur. ThereforeHowever, bu protokolü diğer tekniklerle birleştirerek daha farklı işleme yöntemleri için olanakları sağlayacaktır. İlk olarak, plazmid DNA hücre içine özel organizatörü birleştiren, nöronlar, glial hücreler ve astrositler hücre türüne özgü transfeksiyon sağlayacaktır. İkincisi, transfeksiyon geçici olduğundan, sonraki hayatında genin fonksiyonunu analiz etmek isteyen bilim adamları için uygun değildir. Bu nedenle, plazmid DNA genom entegre olmak için bir transposase ile birlikte istikrarlı bir transfeksiyon 8 dönüştürmek . Tet-veya tet-off sistemi, evlat edinme 8 sinir hücreleri veya hücre tipine özgü gen ekspresyonu zamanlama işlemek için mümkün kılacaktır. Alternatif olarak, bu protokol tamoksifen-indüklenebilir Cre-ER (T) recombinases 9 ve muhabir fareler 10 birleştirebilirsiniz. Dokuların Bu geniş erişilebilirlik nörobilim kullanılan deneysel tasarımları büyük ölçüde değişecektir.

<table border="1"><tbody><tr><td> Reaktifin Adı </td><td> Şirket </td><td> Katalog numarası </td></tr><tr><td> çıplak tungsten tel çapı 125 mm </td><td> AM sistemleri </td><td> 797600 </td></tr><tr><td> çıplak platin tel çapı 125 mm </td><td> AM sistemleri </td><td> 767000 </td></tr><tr><td> Çubuk elektrotlar </td><td> Nepa gen </td><td> CUY610P4-1 </td></tr><tr><td> Cam kılcal tüp </td><td> Stoelting </td><td> 50611 </td></tr><tr><td> mikromanipülatör </td><td> KD Bilimsel </td><td> KDS310 </td></tr><tr><td> makas </td><td> ROBOZ </td><td> RS-5865 </td></tr><tr><td> darbe jeneratörü </td><td> AM Sistemleri </td><td> Model 2100 </td></tr><tr><td> 9 mm AutoCLIP </td><td> ROBOZ </td><td> RS-9260 </td></tr><tr><td> altın kaplama pinler </td><td> TEFE </td><td> 5482 </td></tr><tr><td> RORC &#39;ün antikor </td><td> Perseus Proteomik </td><td> H3925 </td></tr></tbody></table>

mouse in utero electroporation: controlled spatiotemporal gene transfection

Gelişmekte olan beyin, sinyal molekülleri ve akson rehberlik molekülleri, yerel gen transferi veya knock-out gereklidir dahil olmak üzere belirli bir bölgedeki genlerin işlevini anlamak için. Knock-knock-out hedefleme Gen yerel bölgeye belirli bir zahmetli, masraflı CRE hattı, ve zaman alıcı bir kombinasyonu ile gerçekleştirmek mümkün. Bu nedenle, basit bir transfeksiyon yöntemi, kısa sürede yapılabilir bir utero elektroporasyon tekniği, transgenik hayvanlar 1,2 nesil öncesinde aday genlerin olası fonksiyon testi için kullanışlı olacaktır. Buna ek olarak, in utero elektroporasyon, belirli bir CRE hattı var olan beyin alanları hedef ve embriyonik öldürücülüğü 3,4 sınırlayacaktır . Burada, biz, basit ve kullanışlı bir gen transferi için iki farklı tür elektrotlar birleştirerek gelişmekte olan beyin hedef alanlara utero elektroporasyon bir yöntem mevcut. İlk olarak, benzersiz bir optik fiber optik ışık kablosu kullanarak bir embriyo tutma yöntemi ventriküller ve hedeflenen beyin alanı 5,6 iğne tipi elektrodlar ekleme içine hedeflenen DNA çözüm enjeksiyon için görünür küçük embriyolar (E9.5) yapacaktır . Bu nedenle, kortikal alanı gibi beyin desenlendirme E9.5 bu erken elektroporasyon tüm alanı desenlendirme olayı anlamak için büyük bir katkı yapmak, erken embriyonik aşamada meydana gelir. İkincisi, bir kılcal kesin şeklini kılcal ekleme delik yaparak rahim zarar görmesini engeller. Ayrıca, iğne elektrotlar kesin şeklini tungsten ve platin tel ile oluşturulan ve zımpara kağıdı kullanarak bilenmiş ve tırnak cilası 7, bu protokol çok detaylı olarak açıklanan bir yöntem ile izole edilir. Bu benzersiz tekniği, beynin sınırlı alanlar içine plazmid DNA transfeksiyon sağlar ve küçük embriyolar electroporated olmasını sağlayacak. Bu, çok erken embriyonik aşamada hücre farklılaşması, hücre göçü, akson rehberliği üzerinde çalışıyoruz birçok bilim adamları için yeni bir pencere açmak için yardımcı olacaktır. Ayrıca, bu teknik, bilim adamları, birçok bölgeye özel CRE hatları fonksiyon kazanç (GOF) veya fonksiyon (LOF) analizleri kaybı var talamus ve hipotalamus, beyin gibi gelişmekte olan derin bölüme plazmid DNA transfect sağlayacaktır.

Watch this Scientific Journal Video about Mouse in Utero Electroporation: Controlled Spatiotemporal Gene Transfection at JoVE.com

Mouse in Utero Electroporation: Controlled Spatiotemporal Gene Transfection

Gelişmekte olan fare beyninin içine bir gen transferi yöntemi eşsiz bir cerrahi yöntem ve elektrotlar özel şekli ile tarif edilir. Bu benzersiz tekniği, beyin gelişimi okuyan birçok Nörobilimadamları yardımcı olacak zamansal ve mekansal plazmid DNA transfeksiyon sağlar.

Fare Utero Elektroporasyon: Kontrollü Spatiotemporal Gen Transfeksiyon

In order to understand the function of genes expressed in specific region of the developing brain, including signaling molecules and axon guidance ...

mouse-utero-electroporation-controlled-spatiotemporal-gene

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JoVE Journal

Neuroscience

Mouse in Utero Electroporation: Controlled Spatiotemporal Gene Transfection

42.7K Görüntüleme.  RIKEN Brain Science Institute. Gelişmekte olan fare beyninin içine bir gen transferi yöntemi eşsiz bir cerrahi yöntem ve elektrotlar özel şekli ile tarif edilir. Bu benzersiz tekniği, beyin gelişimi okuyan birçok Nörobilimadamları yardımcı olacak zamansal ve mekansal plazmid DNA transfeksiyon sağlar.

Video: Mouse in Utero Electroporation: Controlled Spatiotemporal Gene Transfection

In utero Electroporation followed by Primary Neuronal Culture for Studying Gene Function in Subset of Cortical Neurons

In vitro study of primary neuronal cultures allows for quantitative analyses of neurite outgrowth. In order to study how genetic alterations affect neuronal process outgrowth, shRNA or cDNA constructs can be introduced into primary neurons via chemical transfection or viral transduction. However, with primary cortical cells, a heterogeneous pool of cell types (glutamatergic neurons from different layers, inhibitory neurons, glial cells) are transfected using these methods. The use of in utero electroporation to introduce DNA constructs in the embryonic rodent cortex allows for certain subsets of cells to be targeted: while electroporation of early embryonic cortex targets deep layers of the cortex, electroporation at late embryonic timepoints targets more superficial layers. Further, differential placement of electrodes across the heads of individual embryos results in the targeting of dorsal-medial versus ventral-lateral regions of the cortex. Following electroporation, transfected cells can be dissected out, dissociated, and plated in vitro for quantitative analysis of neurite outgrowth. Here, we provide a step-by-step method to quantitatively measure neuronal process outgrowth in subsets of cortical cells.
The basic protocol for in utero electroporation has been described in detail in two other JoVE articles from the Kriegstein lab 1, 2. We will provide an overview of our protocol for in utero electroporation, focusing on the most important details, followed by a description of our protocol that applies in utero electroporation to the study of gene function in neuronal process outgrowth.

In utero Electroporation followed by Primary Neuronal Culture for Studying Gene Function in Subset of Cortical Neurons

In utero electroporation is a valuable method for transfecting neuronal progenitor cells in vivo. Depending upon the placement of the electrodes and the developmental timepoint of electroporation, certain subsets of cortical cells can be targeted. Targeted cells can then be analyzed in vivo or in vitro for effects of genetic alteration.

In utero Elektroporasyon Kortikal nöronlar Altküme Gen Fonksiyonu Öğrenmenin İlköğretim Nöronal Kültür takip

In vitro study of primary neuronal cultures allows for quantitative analyses of neurite outgrowth. In order to study how genetic alterations affect ...

Nörobilim

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural connectivity form during development. In mice, retinofugal projections are arranged in a topographic manner and form eye-specific layers in the Lateral Geniculate Nucleus (dLGN) of the thalamus and the Superior Colliculus (SC). The development of these precise patterns of retinofugal projections has typically been studied by labeling populations of RGCs with fluorescent dyes and tracers, such as horseradish peroxidase1-4. However, these methods are too coarse to provide insight into developmental changes in individual RGC axonal arbor morphology that are the basis of retinotopic map formation. They also do not allow for the genetic manipulation of RGCs.
Recently, electroporation has become an effective method for providing precise spatial and temporal control for delivery of charged molecules into the retina5-11. Current retinal electroporation protocols do not allow for genetic manipulation and tracing of retinofugal projections of a single or small cluster of RGCs in postnatal mice. It has been argued that postnatal in vivo electroporation is not a viable method for transfecting RGCs since the labeling efficiency is extremely low and hence requires targeting at embryonic ages when RGC progenitors are undergoing differentiation and proliferation6. 
In this video we describe an in vivo electroporation protocol for targeted delivery of genes, shRNA, and fluorescent dextrans to murine RGCs postnatally. This technique provides a cost effective, fast and relatively easy platform for efficient screening of candidate genes involved in several aspects of neural development including axon retraction, branching, lamination, regeneration and synapse formation at various stages of circuit development. In summary we describe here a valuable tool which will provide further insights into the molecular mechanisms underlying sensory map development.

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

We demonstrate an in vivo electroporation protocol for transfecting single or small clusters of retinal ganglion cells (RGCs) and other retinal cell types in postnatal mice over a wide range of ages. The ability to label and genetically manipulate postnatal RGCs in vivo is a powerful tool for developmental studies.

Fare Retina Ganglion Hücreleri Transfeksiyon tarafından In vivo Elektroporasyon

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural ...

Efficient Gene Delivery into Multiple CNS Territories Using In Utero Electroporation

The ability to manipulate gene expression is the cornerstone of modern day experimental embryology, leading to the elucidation of multiple developmental pathways. Several powerful and well established transgenic technologies are available to manipulate gene expression levels in mouse, allowing for the generation of both loss- and gain-of-function models. However, the generation of mouse transgenics is both costly and time consuming. Alternative methods of gene manipulation have therefore been widely sought. In utero electroporation is a method of gene delivery into live mouse embryos1,2 that we have successfully adapted3,4. It is largely based on the success of in ovo electroporation technologies that are commonly used in chick5. Briefly, DNA is injected into the open ventricles of the developing brain and the application of an electrical current causes the formation of transient pores in cell membranes, allowing for the uptake of DNA into the cell. In our hands, embryos can be efficiently electroporated as early as embryonic day (E) 11.5, while the targeting of younger embryos would require an ultrasound-guided microinjection protocol, as previously described6. Conversely, E15.5 is the latest stage we can easily electroporate, due to the onset of parietal and frontal bone differentiation, which hampers microinjection into the brain. In contrast, the retina is accessible through the end of embryogenesis. Embryos can be collected at any time point throughout the embryonic or early postnatal period. Injection of a reporter construct facilitates the identification of transfected cells.
To date, in utero electroporation has been most widely used for the analysis of neocortical development1,2,3,4. More recent studies have targeted the embryonic retina7,8,9 and thalamus10,11,12. Here, we present a modified in utero electroporation protocol that can be easily adapted to target different domains of the embryonic CNS. We provide evidence that by using this technique, we can target the embryonic telencephalon, diencephalon and retina. Representative results are presented, first showing the use of this technique to introduce DNA expression constructs into the lateral ventricles, allowing us to monitor progenitor maturation, differentiation and migration in the embryonic telencephalon. We also show that this technique can be used to target DNA to the diencephalic territories surrounding the 3rd ventricle, allowing the migratory routes of differentiating neurons into diencephalic nuclei to be monitored. Finally, we show that the use of micromanipulators allows us to accurately introduce DNA constructs into small target areas, including the subretinal space, allowing us to analyse the effects of manipulating gene expression on retinal development.

Efficient Gene Delivery into Multiple CNS Territories Using In Utero Electroporation

In utero electroporation allows for rapid gene delivery in a spatially- and temporally-controlled manner in the developing central nervous system (CNS). Here we describe a highly adaptable in utero electroporation protocol that can be used to deliver expression constructs into multiple embryonic CNS domains, including the telencephalon, diencephalon and retina.

Verimli kullanarak birden çok CNS Topraklar&#39;da Gen Teslimat In Utero Elektroporasyon

The ability to manipulate gene expression is the cornerstone of modern day experimental embryology, leading to the elucidation of multiple developmental ...

Gene Transfer to the Developing Mouse Inner Ear by In Vivo Electroporation

The mammalian inner ear has 6 distinct sensory epithelia: 3 cristae in the ampullae of the semicircular canals; maculae in the utricle and saccule; and the organ of Corti in the coiled cochlea. The cristae and maculae contain vestibular hair cells that transduce mechanical stimuli to subserve the special sense of balance, while auditory hair cells in the organ of Corti are the primary transducers for hearing 1. Cell fate specification in these sensory epithelia and morphogenesis of the semicircular canals and cochlea take place during the second week of gestation in the mouse and are largely completed before birth 2,3. Developmental studies of the mouse inner ear are routinely conducted by harvesting transgenic embryos at different embryonic or postnatal stages to gain insight into the molecular basis of cellular and/or morphological phenotypes 4,5. We hypothesize that gene transfer to the developing mouse inner ear in utero in the context of gain- and loss-of-function studies represents a complimentary approach to traditional mouse transgenesis for the interrogation of the genetic mechanisms underlying mammalian inner ear development6.
The experimental paradigm to conduct gene misexpression studies in the developing mouse inner ear demonstrated here resolves into three general steps: 1) ventral laparotomy; 2) transuterine microinjection; and 3) in vivo electroporation. Ventral laparotomy is a mouse survival surgical technique that permits externalization of the uterus to gain experimental access to the implanted embryos7. Transuterine microinjection is the use of beveled, glass capillary micropipettes to introduce expression plasmid into the lumen of the otic vesicle or otocyst. In vivo electroporation is the application of square wave, direct current pulses to drive expression plasmid into progenitor cells8-10. 
We previously described this electroporation-based gene transfer technique and included detailed notes on each step of the protocol11. Mouse experimental embryological techniques can be difficult to learn from prose and still images alone. In the present work, we demonstrate the 3 steps in the gene transfer procedure. Most critically, we deploy digital video microscopy to show precisely how to: 1) identify embryo orientation in utero; 2) reorient embryos for targeting injections to the otocyst; 3) microinject DNA mixed with tracer dye solution into the otocyst at embryonic days 11.5 and 12.5; 4) electroporate the injected otocyst; and 5) label electroporated embryos for postnatal selection at birth. We provide representative examples of successfully transfected inner ears; a pictorial guide to the most common causes of otocyst mistargeting; discuss how to avoid common methodological errors; and present guidelines for writing an in utero gene transfer animal care protocol.

Gene Transfer to the Developing Mouse Inner Ear by In Vivo Electroporation

The mouse inner ear is a placode-derived sensory organ whose developmental program is elaborated during gestation. We define an in utero gene transfer technique consisting of three steps: mouse ventral laparotomy, transuterine microinjection, and in vivo electroporation. We use digital video microscopy to demonstrate the critical experimental embryological techniques.

Tarafından geliştirilmesi Fare İç Kulak için Gen Transferi<em&gt; In Vivo</em&gt; Elektroporasyon

The mammalian inner ear has 6 distinct sensory epithelia: 3 cristae in the ampullae of the semicircular canals; maculae in the utricle and saccule; and ...

Visualization and Genetic Manipulation of Dendrites and Spines in the Mouse Cerebral Cortex and Hippocampus using In utero Electroporation

In utero electroporation (IUE) has become a powerful technique to study the development of different regions of the embryonic nervous system 1-5. To date this tool has been widely used to study the regulation of cellular proliferation, differentiation and neuronal migration especially in the developing cerebral cortex 6-8. Here we detail our protocol to electroporate in utero the cerebral cortex and the hippocampus and provide evidence that this approach can be used to study dendrites and spines in these two cerebral regions.
Visualization and manipulation of neurons in primary cultures have contributed to a better understanding of the processes involved in dendrite, spine and synapse development. However neurons growing in vitro are not exposed to all the physiological cues that can affect dendrite and/or spine formation and maintenance during normal development. Our knowledge of dendrite and spine structures in vivo in wild-type or mutant mice comes mostly from observations using the Golgi-Cox method 9. However, Golgi staining is considered to be unpredictable. Indeed, groups of nerve cells and fiber tracts are labeled randomly, with particular areas often appearing completely stained while adjacent areas are devoid of staining. Recent studies have shown that IUE of fluorescent constructs represents an attractive alternative method to study dendrites, spines as well as synapses in mutant / wild-type mice 10-11 (Figure 1A). Moreover in comparison to the generation of mouse knockouts, IUE represents a rapid approach to perform gain and loss of function studies in specific population of cells during a specific time window. In addition, IUE has been successfully used with inducible gene expression or inducible RNAi approaches to refine the temporal control over the expression of a gene or shRNA 12. These advantages of IUE have thus opened new dimensions to study the effect of gene expression/suppression on dendrites and spines not only in specific cerebral structures (Figure 1B) but also at a specific time point of development (Figure 1C).
Finally, IUE provides a useful tool to identify functional interactions between genes involved in dendrite, spine and/or synapse development. Indeed, in contrast to other gene transfer methods such as virus, it is straightforward to combine multiple RNAi or transgenes in the same population of cells. 
In summary, IUE is a powerful method that has already contributed to the characterization of molecular mechanisms underlying brain function and disease and it should also be useful in the study of dendrites and spines.

Visualization and Genetic Manipulation of Dendrites and Spines in the Mouse Cerebral Cortex and Hippocampus using In utero Electroporation

This article describes in detail a protocol to electroporate in utero the cerebral cortex and the hippocampus at E14.5 in mice. We also show that this is a valuable method to study dendrites and spines in these two cerebral regions.

Kullanarak Fare Serebral Korteks ve Hippocampus Görselleştirme ve Dendritler ve Spine Genetik Manipülasyon<em&gt; Utero olarak</em&gt; Elektroporasyon

In utero electroporation (IUE) has become a powerful technique to study the development of different regions of the embryonic nervous system 1-5. To date ...

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the use of IUE for investigating behavior or neuropathology in the adult brain has been limited by insufficient methods for monitoring of IUE transfection success by non-invasive techniques in postnatal animals. 
 For the present study, E16 rats were used for IUE. After intraventricular injection of the nucleic acids into the embryos, positioning of the tweezer electrodes was critical for targeting either the developing cortex or the hippocampus. 
 Ventricular co-injection and electroporation of a luciferase gene allowed monitoring of the transfected cells postnatally after intraperitoneal luciferin injection in the anesthetized live P7 pup by in vivo bioluminescence, using an IVIS Spectrum device with 3D quantification software. 
 Area definition by bioluminescence could clearly differentiate between cortical and hippocampal electroporations and detect a signal longitudinally over time up to 5 weeks after birth. This imaging technique allowed us to select pups with a sufficient number of transfected cells assumed necessary for triggering biological effects and, subsequently, to perform behavioral investigations at 3 month of age. As an example, this study demonstrates that IUE with the human full length DISC1 gene into the rat cortex led to amphetamine hypersensitivity. Co-transfected GFP could be detected in neurons by post mortem fluorescence microscopy in cryosections indicating gene expression present at &ge;6 months after birth.
 We conclude that postnatal bioluminescence imaging allows evaluating the success of transient transfections with IUE in rats. Investigations on the influence of topical gene manipulations during neurodevelopment on the adult brain and its connectivity are greatly facilitated. For many scientific questions, this technique can supplement or even replace the use of transgenic rats and provide a novel technology for behavioral neuroscience.

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

Genes can be manipulated during development of the cortex or the hippocampus of the rat via in utero electroporation (IUE) at E16, to enable fast and targeted modifications in neuronal connectivity for later studies of behavior or neuropathology in adult animals. Postnatal in vivo imaging for control of IUE success is performed by bioluminescence of activating co-transfected luciferase.

Topikal Transgenik Rats nesil tarafından<em&gt; Utero</em&gt; Elektroporasyon ve<em&gt; In vivo</em&gt; Biyoparlaklık Eleme

 In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the ...

Genetic Manipulation of the Mouse Developing Hypothalamus through In utero Electroporation

Genetic modification of specific regions of the developing mammalian brain is a very powerful experimental approach. However, generating novel mouse mutants is often frustratingly slow. It has been shown that access to the mouse brain developing in utero with reasonable post-operatory survival is possible. Still, results with this procedure have been reported almost exclusively for the most superficial and easily accessible part of the developing brain, i.e. the cortex. The thalamus, a narrower and more medial region, has proven more difficult to target. Transfection into deeper nuclei, especially those of the hypothalamus, is perhaps the most challenging and therefore very few results have been reported. Here we demonstrate a procedure to target the entire hypothalamic neuroepithelium or part of it (hypothalamic regions) for transfection through electroporation. The keys to our approach are longer narcosis times, injection in the third ventricle, and appropriate kind and positioning of the electrodes. Additionally, we show results of targeting and subsequent histological analysis of the most recessed hypothalamic nucleus, the mammillary body.

Genetic Manipulation of the Mouse Developing Hypothalamus through In utero Electroporation

Despite the functional and medical importance of the hypothalamus, in utero genetic manipulation of its development has rarely been attempted. We show a detailed procedure for in utero electroporation into the mouse hypothalamus and show representative results of total and partial (regional) hypothalamic transfection.

Fare Genetik Manipülasyon yoluyla Hipotalamus geliştirilmesi<em&gt; Utero olarak</em&gt; Elektroporasyon

Genetic  modification of specific regions of the developing mammalian brain is a very  powerful experimental approach. However, generating novel mouse ...

Cortex-, Hippocampus-, Thalamus-, Hypothalamus-, Lateral Septal Nucleus- and Striatum-specific In Utero Electroporation in the C57BL/6 Mouse

In utero electroporation is a widely used technique for fast and efficient spatiotemporal manipulation of various genes in the rodent central nervous system. Overexpression of desired genes is just as possible as shRNA mediated loss-of-function studies. Therefore it offers a wide range of applications. The feasibility to target particular cells in a distinct area further increases the range of potential applications of this very useful method. For efficiently targeting specific regions knowledge about the subtleties, such as the embryonic stage, the voltage to apply and most importantly the position of the electrodes, is indispensable.
Here, we provide a detailed protocol that allows for specific and efficient in utero electroporation of several regions of the C57BL/6 mouse central nervous system. In particular it is shown how to transfect regions the develop into the retrosplenial cortex, the motor cortex, the somatosensory cortex, the piriform cortex, the cornu ammonis 1-3, the dentate gyrus, the striatum, the lateral septal nucleus, the thalamus and the hypothalamus. For this information about the appropriate embryonic stage, the appropriate voltage for the corresponding embryonic stage is provided. Most importantly an angle-map, which indicates the appropriate position of the positive pole, is depicted. This standardized protocol helps to facilitate efficient in utero electroporation, which might also lead to a reduced number of animals.

Cortex-, Hippocampus-, Thalamus-, Hypothalamus-, Lateral Septal Nucleus- and Striatum-specific In Utero Electroporation in the C57BL/6 Mouse

This protocol describes in detail how to specifically transfect different regions in the C57BL/6 central nervous system via in utero electroporation. Included in this protocol are detailed instructions for transfections of regions that develop into the cortex, hippocampus, thalamus, hypothalamus, lateral septal nucleus and striatum.

Korteks, Hippocampus-, Thalamus-, Hypothalamus-, Lateral Septal Nucleus- ve Striatum özgü<em&gt; In Utero</em&gt; C57BL / 6 Fare Elektroporasyon

In utero electroporation is a widely used technique for fast and efficient spatiotemporal manipulation of various genes in the rodent central nervous ...

Time-lapse Confocal Imaging of Migrating Neurons in Organotypic Slice Culture of Embryonic Mouse Brain Using In Utero Electroporation

In utero electroporation is a rapid and powerful approach to study the process of radial migration in the cerebral cortex of developing mouse embryos. It has helped to describe the different steps of radial migration and characterize the molecular mechanisms controlling this process. To directly and dynamically analyze migrating neurons they have to be traced over time. This protocol describes a workflow that combines in utero electroporation with organotypic slice culture and time-lapse confocal imaging, which allows for a direct examination and dynamic analysis of radially migrating cortical neurons. Furthermore, detailed characterization of migrating neurons, such as migration speed, speed profiles, as well as radial orientation changes, is possible. The method can easily be adapted to perform functional analyses of genes of interest in radially migrating cortical neurons by loss and gain of function as well as rescue experiments. Time-lapse imaging of migrating neurons is a state-of-the-art technique that once established is a potent tool to study the development of the cerebral cortex in mouse models of neuronal migration disorders.

Time-lapse Confocal Imaging of Migrating Neurons in Organotypic Slice Culture of Embryonic Mouse Brain Using In Utero Electroporation

This protocol provides instructions for direct observation of radially migrating cortical neurons. In utero electroporation, organotypic slice culture, and time-lapse confocal imaging are combined to directly and dynamically study the effects of overexpression or downregulation of genes of interest in migrating neurons and to analyze their differentiation during development.

Embriyonik Fare Beyni Organotipik Dilim Kültüründe Nöronların Geçiş Sürekli Konfokal Görüntüleme Kullanımı<em&gt; Utero&#39;da</em&gt; Elektroporasyon

In utero electroporation is a rapid and powerful approach to study the process of radial migration in the cerebral cortex of developing mouse embryos. It ...

Inducing Cre-lox Recombination in Mouse Cerebral Cortex Through In Utero Electroporation

Cell-autonomous neuronal functions of genes can be revealed by causing loss or gain of function of a gene in a small and sparse population of neurons. To do so requires generating a mosaic in which neurons with loss or gain of function of a gene are surrounded by genetically unperturbed tissue. Here, we combine the Cre-lox recombination system with in utero electroporation in order to generate mosaic brain tissue that can be used to study the cell-autonomous function of genes in neurons. DNA constructs (available through repositories), coding for a fluorescent label and Cre recombinase, are introduced into developing cortical neurons containing genes flanked with loxP sites in the brains of mouse embryos using in utero electroporation. Additionally, we describe various adaptations to the in utero electroporation method that increase survivability and reproducibility. This method also involves establishing a titer for Cre-mediated recombination in a sparse or dense population of neurons. Histological preparations of labeled brain tissue do not require (but can be adapted to) immunohistochemistry. The constructs used guarantee that fluorescently labeled neurons carry the gene for Cre recombinase. Histological preparations allow morphological analysis of neurons through confocal imaging of dendritic and axonal arbors and dendritic spines. Because loss or gain of function is achieved in sparse mosaic tissue, this method permits the study of cell-autonomous necessity and sufficiency of gene products in vivo.

Inducing Cre-lox Recombination in Mouse Cerebral Cortex Through In Utero Electroporation

Cell-autonomous functions of genes in the brain can be studied by inducing loss or gain of function in sparse populations of cells. Here, we describe in utero electroporation to deliver Cre recombinase into sparse populations of developing cortical neurons with floxed genes to cause loss of function in vivo.

CRE-lox rekombinasyon fare serebral korteks rahim içinde elektroporasyon ile inducing

Cell-autonomous neuronal functions of genes can be revealed by causing loss or gain of function of a gene in a small and sparse population of neurons. To ...