In utero Electroporation followed by Primary Neuronal Culture for Studying Gene Function in Subset of Cortical Neurons
Summary
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.
Abstract
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.
Protocol
Discussion
In vitro study of primary neuronal cultures allow for quantitative analyses of neurite outgrowth. In order to study how genetic alterations affect neuronal process outgrowth, shRNA or misexpression 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 e…
Disclosures
The authors have nothing to disclose.
Acknowledgements
The authors would like to thank Joseph LoTurco and Dennis Selkoe for helpful discussions on this technique. The authors thank the donors of the American Health Assistance Foundation, for support of this research.
Materials
| Material Name | Type | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| Cortical Neuron Preparation | ||||
| Dissection Media: | ||||
| 10X Hanks’ Balanced Salt Solution (HBSS) (Ca+2 /Mg +2 free) | Gibco | 14185-052 | ||
| 10X Hanks’ Balanced Salt Solution (HBSS) (with Ca+2 /Mg +2 ) | Gibco | 14065-056 | ||
| 1M HEPES pH 7.4 | Gibco | 15630-080 | ||
| Dishes and Vials: | ||||
| 100 x 15 mm Petri Dishes | Fisherbrand | 08-757-12 | ||
| 60 x 15 mm Petri Dishes | BD Falcon | 351007 | ||
| 15 mL conical vial | Sarstedt | 62-547-205 | ||
| 50 mL conical vial | Sarstedt | 62-554-205 | ||
| Dissection Tools: | ||||
| Scissors | Fine Science Tools | 91402-12 | ||
| Standard Forceps | Fine Science Tools | 11000-12 | ||
| Curved Forceps | Fine Science Tools | 11273-20 | ||
| Fine Forceps | Fine Science Tools | 11255-20 | ||
| Vannas spring scissors | Fine Science Tools | 15000-00 | ||
| Miscellaneous: | ||||
| .25% Trypsin-EDTA | Gibco | 25200 | ||
| Reichert Bright-Line Hemacytometer | Hausser Scientific | 1490 | ||
| Hand-Held Tally Counter | Sigma | Z169021 | ||
| Plating Medium: | ||||
| Dulbecco’s Modified Eagle Medium (D-MEM) | Gibco | 11960-051 | ||
| Fetal Bovine Serum | Sigma | F4135 | ||
| Penicillin-Streptomycin | Gibco | 15140 | ||
| L-glutamine | Gibco | 25030 | ||
| Growth Medium: | ||||
| NEUROBASAL Medium | Gibco | 21103-049 | ||
| B-27 Serum-Free Supplement | Gibco | 17504-044 | ||
| GlutaMAX -I Supplement | Gibco | 35050-061 | ||
| Gentamicin Reagent Solution | Gibco | 15750-060 | ||
| Immunostaining: | ||||
| Fixative, Washes, and Blocking Buffer: | ||||
| Paraformaldehyde | Sigma | P6148 | ||
| Phosphate Buffered Saline | Sigma | P4417 | ||
| Triton X-100 | Sigma | T9284 | ||
| Donkey Serum | Jackson Immuno | 017-000-121 | ||
| Antibodies: | ||||
| beta-III tubulin antibody | Chemicon | MAB1637 | ||
| MAP2 antibody | Chemicon | AB15452 | ||
| Donkey Cy3 anti-mouse | Jackson Immuno | 715-166-151 | ||
| Donkey Cy2 anti-chicken | Jackson Immuno | 703-226-155 | ||
| DAPI | Gibco | D3571 | ||
| Slide Preparation: | ||||
| CC2 Coated Two-Chamber Slides | Lab-Tek | 154852 | ||
| Fluorescent Mounting Media | KPL | 71-00-16 | ||
| 24 x 60 mm Micro Cover Glasses | VWR | 48393-106 | ||
| Clear nail polish | Electron Microscopy Sciences | 72180 | ||
| Electroporation: | ||||
| Ketamine | Henry Schein | 995-2949 | ||
| Xylazine | Henry Schein | 4015809TV | ||
| buprenorphine | Henry Schein | 1118217 | ||
| Picospritzer III | Parker | |||
| BTX square wave electroporator | Fisher | BTXECM830 | ||
| Tweezertrodes, 7 mm, platinum | Harvard Apparatus | 450488 |
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