该协议将演示如何生成的果蝇眼睛/触角成虫盘(EAD)荧光标记,基因定义克隆肿瘤。它介绍了如何从第三龄幼虫,以及如何处理它们的可视化和量化基因表达的变化和肿瘤的侵袭性解剖EAD和大脑。
Drosophila melanogaster has emerged as a powerful experimental system for functional and mechanistic studies of tumor development and progression in the context of a whole organism. Sophisticated techniques to generate genetic mosaics facilitate induction of visually marked, genetically defined clones surrounded by normal tissue. The clones can be analyzed through diverse molecular, cellular and omics approaches. This study describes how to generate fluorescently labeled clonal tumors of varying malignancy in the eye/antennal imaginal discs (EAD) of Drosophila larvae using the Mosaic Analysis with a Repressible Cell Marker (MARCM) technique. It describes procedures how to recover the mosaic EAD and brain from the larvae and how to process them for simultaneous imaging of fluorescent transgenic reporters and antibody staining. To facilitate molecular characterization of the mosaic tissue, we describe a protocol for isolation of total RNA from the EAD. The dissection procedure is suitable to recover EAD and brains from any larval stage. The fixation and staining protocol for imaginal discs works with a number of transgenic reporters and antibodies that recognize Drosophila proteins. The protocol for RNA isolation can be applied to various larval organs, whole larvae, and adult flies. Total RNA can be used for profiling of gene expression changes using candidate or genome-wide approaches. Finally, we detail a method for quantifying invasiveness of the clonal tumors. Although this method has limited use, its underlying concept is broadly applicable to other quantitative studies where cognitive bias must be avoided.
癌代表了最遗传异质组疾病,其发病率和死亡率的显着提高,特别是在老年人全世界之一。癌症从逃脱固有的抑癌机制,并把失控的肿瘤启动细胞克隆起源。遗传病变共同促进生长,增殖和迁移,同时抑制死亡和分化的逐渐积累转化的初始良性增生为高度恶性,转移性和致命的肿瘤。它已成为明显的是,除了遗传改变,肿瘤进展需要在肿瘤和多种细胞类型( 例如 ,成纤维细胞,免疫细胞和内皮细胞)在其微环境之间的周围的基质和串扰的改变。理解的分子原理恶变底层包括肿瘤 – 基质的相互作用是非常重要的发展防止措施灰和早期筛查策略,以及新的和有效的治疗方法,以打击癌症转移和耐药性。
果蝇果蝇已成为癌症研究1-4由于其快速产生时间一个有吸引力的系统,信令苍蝇和人类的促进几乎任何基因操纵在先进遗传工具有限遗传冗余和财富之间节点的显着的保护一个暂时和空间限制的方式。不同的恶性肿瘤的遗传背景明确肿瘤可在果蝇通过使用MARCM技术5在另外的野生型组织中祖细胞的一个子集引入GAIN-和丧失功能的突变再现地工程化。该MARCM工具结合FLP / FRT(FLP重组/ FLP识别目标)介导的有丝分裂重组6 FLP出7和Gal4的/ UAS(上游激活序列)8靶基因表达系统9。与任何基于UAS – 转基因的这种方法的表达,包括原癌基因或荧光蛋白的cDNA或倒置DNA重复对的dsRNA诱导的基因沉默,将被限制到细胞的克隆已经失去一个特定基因座和一个Gal4的阻遏由于重组( 图1A)。标有绿色荧光(GFP)或红色荧光蛋白克隆补丁( 例如,RFP,红色荧光蛋白,mCherry)可以很容易地在整个发展,孤立和分析跟踪。重要的是,它们的行为可以直接比较到相邻的野生型组织。因此,问题相关的所述细胞的遗传病变的自主性和非自主效应可以方便地研究。类似于哺乳动物,只有克隆,其中多个致癌病变被组合成为在果蝇恶性和概括哺乳动物癌细胞的关键特点。他们overproliferate,逃避凋亡,诱发炎症,成仙INVA西伯,最终杀死宿主10-17。
在这里,我们描述了一个协议,使用MARCM技术产生果蝇幼虫的眼睛/触角和脑组织基因定义克隆肿瘤。该方法依赖于一个MARCM仪股票其表达无眼增强剂(eyFLP)18,19的控制下的酵母FLP重组酶。以这种方式,在EAD的两个peripodial和柱状上皮和脑的整个胚胎和幼虫期( 图1A,B和参考20)的神经上皮产生GFP标记的克隆。克隆可以轻松跟随直到成年的EAD发展到成人的眼睛,天线和头壳而神经上皮产生了产生差异化的视叶神经元的神经细胞。
为了方便马赛克组织,我们去的大量分子,功能和表型特征隶从三龄幼虫EAD和大脑的解剖协议,并概述了如何处理它们三个不同的应用程序:(一)检测转基因荧光记者和染色,(二)肿瘤侵袭和(三)分析量化基因表达的变化使用定量实时PCR(QRT-PCR)或高通量的mRNA测序(的mRNA-SEQ)( 图1C)。
免疫染色协议可以用于可视化的任何感兴趣的蛋白质的特异性抗体。转基因荧光转录记者提供对特定信号传导途径的活性方便和精确的时空信息。细胞谱系特异性记者,另一方面,反映镶嵌组织内和不同的基因型的肿瘤中的细胞群体的定性和定量的变化。的入侵行为有利于量化基因型与肿瘤恶性的比较秒。最后,描述用于RNA分离镶嵌EAD的收集和处理的协议,适用于小型和大型的下游应用如逆转录随后分别定量RT-PCR和基因组范围内的mRNA-SEQ。从这些分析得到的定性和定量的数据提供新的见解克隆肿瘤的社会行为。此外,它们产生用于对各个基因,遗传网络和在不同阶段肿瘤微环境和肿瘤发生的各方面的作用,功能研究了坚实的基础。
该技术产生在果蝇遗传马赛克是用于分析和操纵基因功能的33最复杂的工具之一。所述eyFLP-MARCM系统已被证明强大和健壮,因为它允许在视觉上标记,遗传背景明确克隆的诱导以空间受限的方式, 即 ,在组织中,其中无眼增强剂是活性9,18。当多种遗传病变在相同的细胞结合,这是特别重要的。虽然这些高度异常的修补程序时只限于EAD和脑部神经上皮使幼虫发?…
The authors have nothing to disclose.
We thank the Bloomington Stock Center (Bloomington, USA), Dirk Bohmann, Katja Brückner and Istvan Ando for fly stocks, and antibodies. We thank Marek Jindra and Colin Donohoe for comments on the manuscript. This work was supported by the Sofja Kovalevskaja Award to M.U. from the Alexander von Humboldt Foundation and DFG project UH243/1-1 to M.U. from the German Research Foundation.
Agar | Gewürzmühle Brecht, Eggenstein, Germany | 00262-0500 | Fly food recipe: Prepare 20 L fly food with 160 g agar, 360 g yeast, 200 g soy flour, 1.6 kg yellow cornmeal, 1.2 L malt extract, 300 ml light corn syrup, 130 ml propionic acid and 200 ml 15% nipagin. Fly food should be cooked for 1 hour at 85°C. |
Corn syrup | Grafschafter Krautfabrik Josef Schmitz KG, Meckenheim, Germany | 01939 | |
Propionic acid | Carl Roth GmbH, Karlsruhe, Germany | 6026.1 | |
Cornmeal | ReformKontor GmbH, Zarrentin, Germany | 4010155063948 | |
Malt extract | CSM Deutschland GmbH, Bremen, Germany | 728985 | |
Soy flour | Stockmeier Food GmbH, Herford, Germany | 1000246441010 | |
Yeast | Werner Ramspeck GmbH, Schwabach, Germany | 210099K | |
Methyl-4-benzoate/ Nipagin | Sigma-Aldrich, Deisenhofen, Germany | H5501 | Prepare a 15% stock solution with 70% EtOH |
Drosophila fly food vials | Kisker Biotech, Steinfurt, Germany | 789008 | |
Vial plugs | K-TK e.K., Retzstadt, Germany | 1002 | |
Drosophila fly food bottles | Greiner Bio-One, Frickenhausen, Germany | 960177 | |
Bottle plugs | K-TK e.K., Retzstadt, Germany | 1002 S | |
Poly(vinyl alcohol) 4-88/[-CH2CHOH-]n | Sigma-Aldrich, Deisenhofen, Germany | 81381 | Mounting medium recipe: Dissolve 6 g Poly(vinyl alcohol) 4-88 in 39 ml Millipore H2O, 6 ml 1 M Tris (pH 8.5) and 12.5 ml glycerol. Stir overnight at 50°C and centrifuge 20 min at 5000 rpm. Add DABCO to the supernatant to get a final concentration of 2.5%. Store aliquots at -20°C. |
1,4-Diazabicyclo[2.2.2]octane/ DABCO | Sigma-Aldrich, Deisenhofen, Germany | D2522 | |
Triton X-100 | Sigma-Aldrich, Deisenhofen, Germany | 9002-93-1 | |
Phosphate-buffered saline/ PBS | 137 mM NaCl, 2.7 mM KCl, 10 mM Na2HPO4 and 1.8 mM KH2PO4, pH 7.4 in Millipore H2O | ||
PBST | 0.1% Triton X-100 in PBS | ||
Paraformaldehyde/ PFA | Sigma-Aldrich, Deisenhofen, Germany | 158127 | 4% PFA fixative recipe: Dissolve 4 g PFA in 80 ml Millipore H2O on a magnetic stirrer plate heated to 55 °C. Add 1M NaOH dropwise until all PFA particles are dissolved. Add 10 ml 10X PBS and adjust the pH to 7.4 with 1M HCl. Mix in 100 µl Triton X-100 and fill up with Millipore H2O to 100 ml. Store aliquots at -20°C. Avoid repeated thawing. (CAUTION: PFA is highly toxic. Prepare the PFA fixative in a fume hood. Wear a self-contained breathing apparatus, gloves and clothing. Avoid contact with skin, eyes or mucous membranes) |
Bovine Serum Albumin/ BSA | Sigma-Aldrich, Deisenhofen, Germany | A3059 | Blocking solution recipe: Dissolve 0.3% BSA in PBST |
4’,6-Diamidino-2-phenylindol Dihydrochlorid/ DAPI | Carl Roth GmbH, Karlsruhe, Germany | 6335 | DAPI staining solution: Prepare a stock solution of 5 mg/ml in Millipore H2O and store aliquots at 4°C. Used in dilution 1:1000 in PBST. |
Alexa Flour 546 Phalloidin | Invitrogen, Karlsruhe, Germany | A22283 | Used in dilution 1:500 in PBST. |
Mouse anti-H2 antibody | Kurucz et al., 2003 | Used in dilution 1:500 in blocking solution | |
Cy5 AffiniPure Donkey Anti-Mouse IgG (H+L) | Jackson ImmunoResearch, Suffolk, UK | 715-175-151 | Used in dilution 1:500 in blocking solution |
Dumont #5 forceps | Fine Science Tools, Heidelberg, Germany | 11295-10 | |
Glass embryo dish (30 mm) | Thermo Scientific, Schwerte, Germany | E90 | |
Tungsten needles | Fine Science Tools, Heidelberg, Germany | 10130-20 | |
Nickel Plated Pin Holder | Fine Science Tools, Heidelberg, Germany | 26018-17 | |
Microscope slides | VWR, Darmstadt, Germany | 631-1553 | |
Coverslips 22 x 22 mm (#1 Menzel-Gläser) | VWR, Darmstadt, Germany | 631-1336 | |
Coverslips 24 x 50 mm (0.13-0.16 mm) | Thermo Scientific, Schwerte, Germany | 1076371 | |
Kimtech Science Precision Wipes | Thermo Scientific, Schwerte, Germany | 06-677-70 | |
Dissecting stereomicroscope | Olympus, Hamburg, Germany | SZX7 (DF PLAPO 1X-4 Japan) | |
Fluorescent stereomicroscope | Olympus, Hamburg, Germany | SZX16 (SDF PLAPO 0.8X Japan) with DP72 CCD camera | Equipped with the narrow blue bandpass filter set for excitation of GFP other blue excitable fluorochromes (excitation filter BP460-480 nm, barrier filter BA495-540 nm) and narrow green excitation and longpass barrier filter for RFP and other green excitable fluorochromes (excitation filter BP530-550, barrier filter BA575IF). Software: Olympus cellSens Standard 1.11. |
Confocal microscope | Olympus, Hamburg, Germany | FV1000 | Equipped with inverted IX81 microscope. Objectives: 20× UPlan S-Apo (NA 0.85), 40× UPlanFL (NA 1.30) and 60× UPlanApo (NA 1.35). Lasers: UV laser Diode LD405 (50mW), Argon laser, multi-line 457/(476)/ 488/515 (40mW), Yellow/Green laser diode LD560 (15mW) and Red Laser diode 635 (20mW). Software: Fluoview 2.1c Software |
Drosophila cooled incubator | Ewald Innovationstechnik GmbH, Bad Nenndorf, Germany | Sanyo MIR553 | |
Squirt bottle | VWR, Darmstadt, Germany | 215-8105 | |
BD Clay Adams Nutator Mixer | VWR, Darmstadt, Germany | 15172-203 | |
ELMI Digital Rocking Shaker | VWR, Darmstadt, Germany | DRS-12 | |
5 PRIME Isol-RNA Lysis Reagent | VWR, Darmstadt, Germany | 2302700 | The protocol is compatible with other TRIzol-based reagents e.g. TRIreagent from Sigma (Cat. Nr.T9424), TRIzol reagent from Thermofisher (Cat. Nr. 15596). |
Diethyl pyrocarbonate/ DEPC | Sigma-Aldrich, Deisenhofen, Germany | D5758 | Dilute DEPC 1:1000 in Millipore H2O, stir overnight and autoclave. |
UltraPure Phenol:Chloroform:Isoamyl Alcohol (25:24:1) | ThermoFischer Scientific, Invitrogen, Karlsruhe, Germany | 15593-031 | |
Chloroform | Merck, Darmstadt, Germany | 102445 | |
TURBO DNase (2 U/µl) | Thermo Scientific, Schwerte, Germany | AM2238 | |
Invitrogen UltraPure Glycogen | ThermoFischer Scientific, Invitrogen, Karlsruhe, Germany | 10-814-010 | |
Sodium acetate trihydrate | VWR, Darmstadt, Germany | 27652.232 | Prepare a 3M Sodium acetate solution with DEPC-H2O and adjust the pH to 5.2 |
2-Propanol | Merck, Darmstadt, Germany | 109634 | |
Ethanol | Merck, Darmstadt, Germany | 100983 | Prepare a 75% EtOH dilution with DEPC-H2O. |
UV/Vis-Spectrophotometre NanoDrop ND-8000 | Thermo Scientific, Schwerte, Germany | ND-8000 | |
Eppendorf Microcentrifuge (Refrigerated) | Thermo Scientific, Schwerte, Germany | 5417R | |
Experion RNA StdSens Analysis Kit | Bio-Rad Laboratories GmbH, München, Germany | 7007103 | |
Experion Automated Electrophoresis Station | Bio-Rad Laboratories GmbH, München, Germany | 7007010 | |
SuperScript III Reverse Transcriptase | Thermo Scientific, Schwerte, Germany | 18080044 | |
Oligo d(T) Primer | Integrated DNA Technologies, Leuven, Belgium | Prepare 100 µM stock solutions in DEPC-H20 and store at -20°C | |
dNTP Mixture | Takara Bio Europe/Clonetech, Saint-Germain-en-Laye, France | 4030 | Store aliquots of 25 µl at -20°C |
CFX96 Touch Real-Time PCR Detection System | Bio-Rad Laboratories GmbH, München, Germany | 1855195 | |
iQ SYBR Green Supermix | Bio-Rad Laboratories GmbH, München, Germany | 170-8882 | |
Hard-Shell PCR Plates 96-well, thin wall | Bio-Rad Laboratories GmbH, München, Germany | HSP9601 | |
Microseal 'B' Film | Bio-Rad Laboratories GmbH, München, Germany | MSB1001 | |
rp49 Forward primer | Integrated DNA Technologies, Leuven, Belgium | 5' TCCTACCAGCTTCAAGATGAC 3' | |
rp49 Reverse primer | Integrated DNA Technologies, Leuven, Belgium | 5' CACGTTGTGCACCAGGAACT 3' | |
mmp1 Forward primer | Integrated DNA Technologies, Leuven, Belgium | 5' AGGGCGACAAGTACTACAAGCTGA 3' | |
mmp1 Reverse primer | Integrated DNA Technologies, Leuven, Belgium | 5' ACGTCTTGCCGTTCTTGTAGGTGA 3' |