Name: rapid genotyping of animals followed by establishing primary cultures of brain neurons
Uploaded: 2015-01-29T13:00:00
Description: Watch this Scientific Journal Video about Rapid Genotyping of Animals Followed by Establishing Primary Cultures of Brain Neurons at JoVE.com

The authors thank researchers at the University of Iowa, Drs. Luis Tecedor, Ines Martins and Beverly Davidson for instructions and helpful comments regarding striatal cultures, and Drs. Kara Gordon, Nicole Bode and Pedro Gonzalez-Alegre for genotyping assistance and discussions. We also thank Dr. Eric Weyand (Animal Identification and Marking Systems) for helpful comments regarding tattooing, and Dr. Shutaro Katsurabayashi (Fukuoka University) for helpful comments regarding the mouse culture. This work was supported by grants from the American Heart Association, the Department of Defense (Peer Reviewed Medical Research Program award W81XWH-14-1-0301), the Dystonia Medical Research Foundation, the Edward Mallinckrodt, Jr. Foundation, the National Science Foundation, and the Whitehall Foundation (N.C.H.).

NOTE: All animal procedures performed in this study were approved by the Institutional Animal Care and Use Committee of the University of Iowa.
1. Long-term Identification of Mice Using Tattooing the Paw Pads
<ol>
	<li>Immobilize a paw with the paw pad (plantar surface) facing the experimenter. Hold the paw with the thumb and the index finger. Be careful not to pinch the paw. 
	NOTE: Stable immobilization is important to ensure that the tattoo pigment is placed into the dermis of the pa...

The protocol presented here includes procedures for tattooing to label/identify mice, for genotyping mice from tail tips, and for culturing mouse brain neurons at low density. In one round of experiments using 6-8 pups, these procedures typically require ~0.5 hr, ~4 hr and ~2 hr, respectively, at a total of 6-7 hr. This makes it practical for a single experimenter to complete all the procedures necessary from the time of the pups&#39; birth to the plating of neuronal cultures &#8211; in less than a single working day (wi...

Rodent models of genetic diseases have proven useful in establishing the physiological functions of normal proteins and nucleic acids, as well as the pathophysiological consequences of defects in these. Examples include mice deficient for proteins involved in key cellular functions, as well as mouse models of disorders such as Alzheimer&#39;s disease. However, certain genetic manipulations can lead to neonatal lethality shortly or a few days after birth. In these cases, primary cell cultures are an important tool because live cells can be obtained from the embryonic or neonatal pups before death, they can be maintained for at least a few weeks in vitro, and during this time early neuronal development can be followed by biochemical, functional and morphological experiments. For the primary cultures, it can be beneficial to plate the neurons at low density; this makes it possible to visualize the individual somata, dendrites, axonal shafts and nerve terminals at high spatial resolution. However, the survival and differentiation of neurons at low density typically requires that they are plated on a glial feeder layer, co-cultured with glial cells in the absence of physical contact with them, or cultured in medium conditioned by glia 1.
The establishment of low-density neuronal cultures on glial feeder layers can be dependent on fast and reliable genotyping beforehand &#8211; within a few hr in contrast to a few days. Speed is especially important when the neuronal genotype needs to be matched to that of a glial feeder layer prepared beforehand. As a more practical example, it may be necessary to decide which pups of which genotype to use in generating cultures, to optimize the efficiency of an experiment.
Here we demonstrate the working protocol that has been used for fast, simplified and reliable mouse genotyping in previous publications 2-6. Mouse tails and a commercially available kit are used. This protocol includes single-step extraction of nucleic acids from the tissue, and requires neither a nucleic-acid purification step nor use of a termination buffer (&#39;stop solution&#39;). The reliability of this genotyping method is illustrated by presenting the results of a series of tests when differences are introduced with respect to the starting amount of the specimens, the age of the animals and the length of the PCR amplicons. This kit offers the advantages of automated extraction and reliability.
For the sake of being comprehensive, the use of tattooing for long-term identification of the genotyped mice is also demonstrated. Tattooing is achieved by applying tattooing ink to the dermis of the skin (under the epidermis) 7. A procedure is described for tattooing the paw pads of newborn or 1 day old mice, although tattoos can be applied to other parts of the body, such as tails and toes, and to animals of all ages. In addition, procedures will be demonstrated for plating and culturing mouse neurons at a low density, based on optimized preparation of different types of glial feeder layers 2,8.
We use a genetic mouse model of the inherited neurological disorder DYT1 dystonia &#8211; an autosomal-dominant movement disorder caused by a mutation in the gene TOR1A (c.904_906delGAG/c.907_909delGAG; p.Glu302del/p.Glu303del) 9. The encoded protein, torsinA, belongs to the &#8220;ATPases associated with diverse cellular activities&#8221; (AAA+) family of proteins, whose members generally perform chaperone-like functions, assisting in: protein unfolding, protein-complex disassembly, membrane trafficking, and vesicle fusion 10-13. The mutation results in an in-frame deletion of a codon for glutamic acid, and can lead to manifestation of &#39;early-onset generalized isolated dystonia&#39; 14,15. However, the pathophysiological mechanisms responsible for this disorder remain poorly understood. In a knock-in mouse model, the mutant allele is Tor1atm2Wtd, mentioned hereafter as Tor1a&#916;E. Heterozygous &#916;E-torsinA knock-in mice are viable and genetically mimic human patients with DYT1 dystonia, whereas homozygous knock-in mice die after birth 16,17, with the latency to postnatal death affected by genetic background 18. The early death of homozygous knock-in mice necessitates that both the genotyping of animals and the establishment of neuronal cultures are completed rapidly. As another example of genotyping, Tfap2a (transcription factor AP-2&#945;, activating enhancer binding protein 2&#945;) will be used. The protein encoded by this gene is important in regulating multiple cellular processes, such as proliferation, differentiation, survival and apoptosis 19.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>REAGENTS - tattooing</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Machine Cleanser</td>
			<td>Animal Identification and Marking Systems, Inc.</td>
			<td>NMCR3</td>
			<td>This is used to clean the needles and the holder after tattooing.</td>
		</tr>
		<tr>
			<td>Machine Drying Agent</td>
			<td>Animal Identification and Marking Systems, Inc.</td>
			<td>NDAR4</td>
			<td>This is used to dry the needles and holder after cleaning.</td>
		</tr>
		<tr>
			<td>Neonate Tattoo Black Pigment</td>
			<td>Animal Identification and Marking Systems, Inc.</td>
			<td>NBP01</td>
			<td></td>
		</tr>
		<tr>
			<td>Skin Prep Applicator</td>
			<td>Animal Identification and Marking Systems, Inc.</td>
			<td>NSPA1</td>
			<td>Q-tip.</td>
		</tr>
		<tr>
			<td>Skin Prep solution</td>
			<td>Animal Identification and Marking Systems, Inc.</td>
			<td>NSP01</td>
			<td>This reagent delivers a thin layer of oil that enhances the efficiency of tattooing and prevents tattoo fading, by (information from vendor): 1) preventing non-tattooed skin from being stained temporarily, thereby allowing the quality of a paw pad tattoo to be easily evaluated before the pup is returned to its home cage &#8211; the stained skin surface can be confused with the tattooed skin, 2) reducing skin damage during tattooing &#8211; softening the skin and lubricating the needle will help the needle penetrate the skin without causing skin damage, and 3) preventing molecular oxygen from entering the skin, thereby reducing inflammatory responses to reactive oxygen species that can be generated.</td>
		</tr>
		<tr>
			<td>REAGENTS - genotyping</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>EZ Fast Tissue/Tail PCR Genotyping Kit (Strip Tube Format)</td>
			<td>EZ BioResearch LLC</td>
			<td>G2001-100</td>
			<td></td>
		</tr>
		<tr>
			<td>2X PCR Ready Mix II</td>
			<td>EZ BioResearch LLC</td>
			<td>G2001-100</td>
			<td>A red, loading dye for electrophoresis is included in the 2X PCR Ready Mix solution.</td>
		</tr>
		<tr>
			<td>Tissue Lysis Solution A</td>
			<td>EZ BioResearch LLC</td>
			<td>G2001-100</td>
			<td>Prepare DNA Extraction Solution by mixing 20 &#181;l of Tissue Lysis Solution A and 180 &#181;l of Tissue Lysis Solution B per specimen.</td>
		</tr>
		<tr>
			<td>Tissue Lysis Solution B</td>
			<td>EZ BioResearch LLC</td>
			<td>G2001-100</td>
			<td>Prepare DNA Extraction Solution by mixing 20 &#181;l of Tissue Lysis Solution A and 180 &#181;l of Tissue Lysis Solution B per specimen.</td>
		</tr>
		<tr>
			<td>Acetic acid, glacial</td>
			<td>VWR</td>
			<td>BDH 3092</td>
			<td></td>
		</tr>
		<tr>
			<td>Agarose optimized grade, molecular biology grade</td>
			<td>rpi</td>
			<td>A20090-500&#160;</td>
			<td>We use 2% agarose gels in TAE buffer containing the SYBR Safe DNA gel stain (diluted 10,000-fold) or ethidium bromide (0.5 &#181;g/ml gel volume).</td>
		</tr>
		<tr>
			<td>Ethidium bromide</td>
			<td>Sigma-Aldrich</td>
			<td>E7637-1G</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethylenediamine tetraacetic acid, disodium salt dihydrate (EDTA)</td>
			<td>Fisher</td>
			<td>BP120-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Filtered Pipet Tips, Aerosol-Free, 0.1-10 &#181;l</td>
			<td>Dot Scientific Inc</td>
			<td>UG104-96RS&#160;</td>
			<td>Use pipette tips that are sterile and free of DNA, RNase and DNase. For all steps involving DNA, use filtered pipette tips to avoid cross-contamination.</td>
		</tr>
		<tr>
			<td>Filtered Pipet Tips, Premium Fit Filter Tips, 0.5-20 &#181;l</td>
			<td>Dot Scientific Inc</td>
			<td>UG2020-RS</td>
			<td>Use pipette tips that are sterile and free of DNA, RNase and DNase. For all steps involving DNA, use filtered pipette tips to avoid cross-contamination.</td>
		</tr>
		<tr>
			<td>Filtered Pipet Tips, Premium Fit Filter Tips, 1-200 &#181;l</td>
			<td>Dot Scientific Inc</td>
			<td>UG2812-RS</td>
			<td>Use pipette tips that are sterile and free of DNA, RNase and DNase. For all steps involving DNA, use filtered pipette tips to avoid cross-contamination.</td>
		</tr>
		<tr>
			<td>Molecular weight marker, EZ DNA Even Ladders 100 bp</td>
			<td>EZ BioResearch LLC</td>
			<td>L1001</td>
			<td>We use either of these three molecular weight markers.</td>
		</tr>
		<tr>
			<td>Molecular weight marker, EZ DNA Even Ladders 1000 bp</td>
			<td>EZ BioResearch LLC</td>
			<td>L1010</td>
			<td></td>
		</tr>
		<tr>
			<td>Molecular weight marker, TrackIt, 100 bp DNA Ladder</td>
			<td>GIBCO-Invitrogen</td>
			<td>10488-058</td>
			<td></td>
		</tr>
		<tr>
			<td>PCR tubes, 8-tube strips with individually attached dome top caps, natural, 0.2 ml&#160;</td>
			<td>USA Scientific</td>
			<td>1402-2900</td>
			<td>Use tubes that are sterile and free of DNA, RNase and DNase. An 8-tube strip is easy to handle and to group the specimens than individual tubes.</td>
		</tr>
		<tr>
			<td>PCR tubes, Ultraflux Individual&#160;</td>
			<td>rpi</td>
			<td>145660</td>
			<td>Use tubes that are sterile and free of DNA, RNase and DNase.</td>
		</tr>
		<tr>
			<td>Seal-Rite 0.5 ml microcentrifuge tube, natural</td>
			<td>USA Scientific</td>
			<td>1605-0000</td>
			<td>Use tubes that are sterile and free of DNA, RNase and DNase.</td>
		</tr>
		<tr>
			<td>SYBR Safe DNA gel stain * 10,000x concentration in DMSO</td>
			<td>GIBCO-Invitrogen</td>
			<td>S33102</td>
			<td></td>
		</tr>
		<tr>
			<td>Tris base</td>
			<td>rpi</td>
			<td>T60040-1000</td>
			<td></td>
		</tr>
		<tr>
			<td>Primers for amplifying Tor1a gene in &#916;E-torsinA knock-in mice</td>
			<td></td>
			<td></td>
			<td>5&#39;-AGT CTG TGG CTG GCT CTC CC-3&#39; (forward) and 5&#39;-CCT CAG GCT GCT CAC AAC CAC-3&#39; (reverse) (reference 18). These primers were used at a final concentration of 1.0 ng/&#181;l (~0.16 &#181;M) (reference 2).</td>
		</tr>
		<tr>
			<td>Primers for amplifying Tfap2a gene in wild-type mice</td>
			<td></td>
			<td></td>
			<td>5&#39;-GAA AGG TGT AGG CAG AAG TTT GTC AGG GC-3&#39; (forward), 5&#39;-CGT GTG GCT GTT GGG GTT GTT GCT GAG GTA-3&#39; (reverse) for the 498-bp amplicon, 5&#39;-CAC CCT ATC AGG GGA GGA CAA CTT TCG-3&#39; (forward), 5&#39;-AGA CAC TCG GGC TTT GGA GAT CAT TC-3&#39; (reverse) for the 983-bp amplicon, and 5&#39;-CAC CCT ATC AGG GGA GGA CAA CTT TCG-3&#39; (forward), 5&#39;-ACA GTG TAG TAA GGC AAA GCA AGG AG-3&#39; (reverse) for the 1990-bp amplicon. These primers are used at 0.5 &#181;M.</td>
		</tr>
		<tr>
			<td>REAGENTS - cell culture</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>5-Fluoro-2&#8242;-deoxyuridine</td>
			<td>Sigma-Aldrich</td>
			<td>F0503-100MG</td>
			<td>See comments section of uridine for more information.</td>
		</tr>
		<tr>
			<td>B-27 supplement</td>
			<td>GIBCO-Invitrogen</td>
			<td>17504-044</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Culture Dishes 35 x 10 mm Dishes, Tissue Culture-treated</td>
			<td>BD falcon</td>
			<td>353001</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Culture Flasks, T25, Tissue Culture-treated, Canted-neck, plug-seal cap, 25 cm2 Growth Area, 70 ml</td>
			<td>BD falcon</td>
			<td>353082</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Culture Flasks, T75, Tissue Culture-treated, Canted-neck, vented cap, 75 cm2 Growth Area, 250 ml</td>
			<td>BD falcon</td>
			<td>353136</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical Tube, polypropylene, 15 ml</td>
			<td>BD falcon</td>
			<td>352095</td>
			<td></td>
		</tr>
		<tr>
			<td>Countess (cell number counter) chamber slides</td>
			<td>GIBCO-Invitrogen</td>
			<td>C10312</td>
			<td></td>
		</tr>
		<tr>
			<td>Cytosine &#946;-D-Arabinofuranoside hydrochloride (Ara-C hydrochloride)</td>
			<td>Sigma-Aldrich</td>
			<td>C6645-100mg</td>
			<td></td>
		</tr>
		<tr>
			<td>D-(+)-Glucose (Dextrose) anhydrous, SigmaUltra, 99.5% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>G7528-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Dish, Petri glass 100 x 15 mm</td>
			<td>Pyrex</td>
			<td>3160-101</td>
			<td></td>
		</tr>
		<tr>
			<td>Distilled water</td>
			<td>GIBCO-Invitrogen</td>
			<td>15230-147</td>
			<td></td>
		</tr>
		<tr>
			<td>DNase Type II</td>
			<td>Sigma-Aldrich</td>
			<td>D4527-200KU</td>
			<td>Stock solution is prepared at 1500 units/20 &#956;l = 75000 units/ml in distilled water.</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle Medium (DMEM), high glucose, GlutaMAX, pyruvate</td>
			<td>GIBCO-Invitrogen</td>
			<td>10569-010, 500 ml</td>
			<td></td>
		</tr>
		<tr>
			<td>Fast PES Filter Unit, 250 ml, 50 mm diameter membrane, 0.2 &#181;m Pore Size</td>
			<td>Nalgene</td>
			<td>568-0020</td>
			<td></td>
		</tr>
		<tr>
			<td>Fast PES Filter Unit, 500 ml, 90 mm diameter membrane, 0.2 &#181;m Pore Size</td>
			<td>Nalgene</td>
			<td>569-0020</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal bovine serum (FBS)</td>
			<td>GIBCO-Invitrogen</td>
			<td>26140-079</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass coverslip, 12 mm Round, thickness 0.09&#8211;0.12 mm, No. 0</td>
			<td>Carolina</td>
			<td>633017</td>
			<td></td>
		</tr>
		<tr>
			<td>GlutaMAX-I</td>
			<td>GIBCO-Invitrogen</td>
			<td>35050-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Hanks&#39; Balanced Salts</td>
			<td>Sigma-Aldrich</td>
			<td>H2387-10X</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES, &#8805;99.5% (titration)</td>
			<td>Sigma-Aldrich</td>
			<td>H3375-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrochloric acid, 37%, A.C.S reagent</td>
			<td>Sigma-Aldrich</td>
			<td>258148-100 ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin</td>
			<td>Sigma-Aldrich</td>
			<td>I5500-250 mg</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium sulfate heptahydrate, MgSO4&#8226;(7H2O), BioUltra, &#8805;99.5% (Fluka)</td>
			<td>Sigma-Aldrich</td>
			<td>63138-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Matrigel Basement Membrane Matrix solution, Phenol Red-Free</td>
			<td>BD Biosciences</td>
			<td>356237</td>
			<td>This is the coating material for coverslips and flasks. 1) To prepare it, thaw the Matrigel Basement Membrane Matrix solution on ice, which usually takes ~1 day. Using a pre-cooled pipette, aliquot the thawed solution into pre-cooled T25 flasks on ice, and store the flasks at -20&#176;C. To prepare the working Matrigel solution, thaw the aliquotted Matrigel in a flask on ice, dilute 50-fold by adding pre-cooled MEM solution and keep the diluted solution at 4&#176;C. It is important to pre-cool all cultureware and media that come into contact with Matrigel, except during and after the coating of coverslips, to prevent it from prematurely forming a gel. 2) To coat the glass coverslips or culture flasks with Matrigel, apply the Matrigel solution to the surface. Before plating cells, it is important to completely dry up the surface. For this purpose, it might be helpful to aspirate Matrigel during the cellular centrifugation immediately before plating the cells and to allow enough time for drying.</td>
		</tr>
		<tr>
			<td>Minimum Essential Medium (MEM)</td>
			<td>GIBCO-Invitrogen</td>
			<td>51200-038</td>
			<td></td>
		</tr>
		<tr>
			<td>MITO+ Serum Extender, 5 ml</td>
			<td>BD Biosciences</td>
			<td>355006</td>
			<td></td>
		</tr>
		<tr>
			<td>Multiwell Plates, Tissue Culture-treated 24-well plate</td>
			<td>BD falcon</td>
			<td>353047</td>
			<td></td>
		</tr>
		<tr>
			<td>Multiwell Plates, Tissue Culture-treated 6-well plate</td>
			<td>BD falcon</td>
			<td>353046</td>
			<td></td>
		</tr>
		<tr>
			<td>Neurobasal-A Medium (1X), liquid</td>
			<td>GIBCO-Invitrogen</td>
			<td>10888-022</td>
			<td></td>
		</tr>
		<tr>
			<td>Nitric Acid</td>
			<td>VWR</td>
			<td>bdh 3044</td>
			<td></td>
		</tr>
		<tr>
			<td>NS (Neuronal Supplement) 21&#160;</td>
			<td>prepared in the lab</td>
			<td></td>
			<td>Source: reference 69</td>
		</tr>
		<tr>
			<td>Pasteur pipets, 5 &#190;&#8221;&#160;</td>
			<td>Fisher</td>
			<td>13-678-6A</td>
			<td>Use this cotton-plugged 5 &#190;&#8221; Pasteur pipette for cellular trituration. Fire-polish the tip beforehand to smooth the cut surface and to reduce the internal diameter to 50-80% of the original. Too small a tip will disrupt the cells and reduce cell viability, but too large a tip will decrease the efficiency of trituration.</td>
		</tr>
		<tr>
			<td>Pasteur pipets, 9&#8221;&#160;</td>
			<td>Fisher</td>
			<td>13-678-6B</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium chloride (KCl), SigmaUltra, &#8805;99.0%</td>
			<td>Sigma-Aldrich</td>
			<td>P9333-500G</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 2 ml</td>
			<td>BD falcon</td>
			<td>357507</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 5 ml&#160;</td>
			<td>BD falcon</td>
			<td>357543</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 10 ml</td>
			<td>BD falcon</td>
			<td>357551</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 25 ml</td>
			<td>BD falcon</td>
			<td>357525</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipet, 50 ml&#160;</td>
			<td>BD falcon</td>
			<td>357550</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium bicarbonate (NaHCO3, Sodium hydrogen carbonate), SigmaUltra, &#8805;99.5%</td>
			<td>Sigma-Aldrich</td>
			<td>S6297-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium chloride (NaCl), SigmaUltra, &#8805;99.5%</td>
			<td>Sigma-Aldrich</td>
			<td>S7653-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium hydroxide (NaOH), pellets, 99.998% trace metals basis</td>
			<td>Sigma-Aldrich</td>
			<td>480878-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium phosphate dibasic heptahydrate (Na2HPO4&#8226;(7H2O)), &#8805;99.99%, Aldrich</td>
			<td>Sigma-Aldrich</td>
			<td>431478-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose, SigmaUltra, &#8805;99.5% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>S7903-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe filter, sterile, 0.2 &#181;m</td>
			<td>Corning</td>
			<td>431219</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe, 3 ml</td>
			<td>BD falcon</td>
			<td>309585</td>
			<td></td>
		</tr>
		<tr>
			<td>Transferrin, Holo, bovine plasma</td>
			<td>Calbiochem</td>
			<td>616420</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue stain, 0.4%</td>
			<td>GIBCO-Invitrogen</td>
			<td>T10282</td>
			<td>This is used for counting live/dead cells. Renew an old trypan blue solution if it is re-used many times (e.g. several times a week for several weeks), because it will form precipitates and result in erroneous readouts of cellular density.</td>
		</tr>
		<tr>
			<td>Trypsin, type XI</td>
			<td>Sigma-Aldrich</td>
			<td>T1005-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA solution, 0.25%&#160;</td>
			<td>GIBCO-Invitrogen</td>
			<td>25200-056</td>
			<td></td>
		</tr>
		<tr>
			<td>Uridine</td>
			<td>Sigma-Aldrich</td>
			<td>U3003-5G</td>
			<td>Stock solution is prepared at 50-mg 5-fluoro-2&#39;-deoxyuridine and 125-mg uridine in 25 ml DMEM (8.12 and 20.48 mM, respectively).</td>
		</tr>
		<tr>
			<td>REAGENTS - immunocytochemistry</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Antibody, rabbit polyclonal anti-MAP2</td>
			<td>Merck Millipore</td>
			<td>AB5622</td>
			<td></td>
		</tr>
		<tr>
			<td>Antibody, mouse monoclonal anti-GFAP cocktail</td>
			<td>Merck Millipore</td>
			<td>NE1015</td>
			<td></td>
		</tr>
	</tbody>
</table>

rapid genotyping of animals followed by establishing primary cultures of brain neurons

High-resolution analysis of the morphology and function of mammalian neurons often requires the genotyping of individual animals followed by the analysis of primary cultures of neurons. We describe a set of procedures for: labeling newborn mice to be genotyped, rapid genotyping, and establishing low-density cultures of brain neurons from these mice. Individual mice are labeled by tattooing, which allows for long-term identification lasting into adulthood. Genotyping by the described protocol is fast and efficient, and allows for automated extraction of nucleic acid with good reliability. This is useful under circumstances where sufficient time for conventional genotyping is not available, e.g., in mice that suffer from neonatal lethality. Primary neuronal cultures are generated at low density, which enables imaging experiments at high spatial resolution. This culture method requires the preparation of glial feeder layers prior to neuronal plating. The protocol is applied in its entirety to a mouse model of the movement disorder DYT1 dystonia (&#916;E-torsinA knock-in mice), and neuronal cultures are prepared from the hippocampus, cerebral cortex and striatum of these mice. This protocol can be applied to mice with other genetic mutations, as well as to animals of other species. Furthermore, individual components of the protocol can be used for isolated sub-projects. Thus this protocol will have wide applications, not only in neuroscience but also in other fields of biological and medical sciences.

As an example of the application of this protocol, representative results are shown for labeling mice by tattooing, reliable genotyping under various experimental conditions, and establishing primary neuronal cultures on glial feeder layers.
Tattooing
Newborn pups were labeled on the paw pads using a tattooing system (&#39;Newborn&#39; in Figure 1). The labels remained clearly visible at 3 weeks (&#39;3-week-old&#39;) and 32 weeks o...

Watch this Scientific Journal Video about Rapid Genotyping of Animals Followed by Establishing Primary Cultures of Brain Neurons at JoVE.com

Rapid Genotyping of Animals Followed by Establishing Primary Cultures of Brain Neurons

We describe procedures for labeling and genotyping newborn mice and generating primary neuronal cultures from them. The genotyping is rapid, efficient and reliable, and allows for automated nucleic-acid extraction. This is especially useful for neonatally lethal mice and their cultures that require prior completion of genotyping.

High-resolution analysis of the morphology and function of mammalian neurons often requires the genotyping of individual animals followed by the analysis ...

Research

JoVE Journal

Neuroscience

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

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 ...

Design and Assembly of an Ultra-light Motorized Microdrive for Chronic Neural Recordings in Small Animals

The ability to chronically record from populations of neurons in freely behaving animals has proven an invaluable tool for dissecting the function of ...

Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange (ABE)

Detection of Protein Palmitoylation in Cultured Hippocampal Neurons by Immunoprecipitation and Acyl-Biotin Exchange ABE

Palmitoylation is a post-translational lipid  modification involving the attachment of a 16-carbon saturated fatty acid,  palmitate, to cysteine residues ...

Calcium Phosphate Transfection of Primary Hippocampal Neurons

Calcium phosphate precipitation is a convenient and economical method for transfection of cultured cells. With optimization, it is possible to use this ...

Primary Culture of Mouse Dopaminergic Neurons

Dopaminergic neurons represent less than 1% of the total number of neurons in the brain. This low amount of neurons regulates important brain functions ...

Isolation, Culture and Long-Term Maintenance of Primary Mesencephalic Dopaminergic Neurons From Embryonic Rodent Brains

Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson&#8217;s diseae. Study of the biological processes ...

Live Imaging Followed by Single Cell Tracking to Monitor Cell Biology and the Lineage Progression of Multiple Neural Populations

Understanding the mechanisms that control critical biological events of neural cell populations, such as proliferation, differentiation, or cell fate ...

Rapid and Specific Immunomagnetic Isolation of Mouse Primary Oligodendrocytes

The efficient and robust isolation and culture of primary oligodendrocytes (OLs) is a valuable tool for the in vitro study of the development of ...

Primary Culture of Neurons Isolated from Embryonic Mouse Cerebellum

The use of primary cell cultures has become one of the major tools to study the nervous system in vitro. The ultimate goal of using this simplified model ...

Multi-Fiber Photometry to Record Neural Activity in Freely-Moving Animals

Recording the activity of a group of neurons in a freely-moving animal is a challenging undertaking. Moreover, as the brain is dissected into smaller and ...