Electroporation is a technique to put DNA in cells to study it's expression, inhibition, to target it or other application.
To do it you need to take some of your target DNA and mix it with a colored solution to see it with your eyes while you manipulate. You really need small quantities (10 microlitres) if your DNA is concentrated and also because embryo are only few millimeter long. You need a capillary made by a machine that heat it and then cut it in two by pulling it in opposite way, the glass is deformable because of the temperature and it will be elongated to a microscopic tube. To use it you need to cut it in the appropriate size for you under the binocular loop with a pliers. Once is ok you put it in a tube to aspirate with you mouth to put DNA liquid in it and breath out to take it off! For an electroporation in the neural tube of the chick you need to extract some of the albumen of the egg with a syringe and make a hole on the top with scissors making sure you don't hit the yolk. Then look at it with the binocular and identify the embryo and the neural tube on the middle there is the veins that are coming and this is where you need to put the DNA because is the only place where the liquid will go up and down to all the tube. So you need to pinch it with the end of the capillary and breath out. When you see all the tube is full you can stop being careful not damage the embryo to much (the embryo regenerate quite nicely at this times). This step can be tricky and many DNA can go around on the top of the embryo and not in the tube, but if some are in it doesn't matters. After you have some DNA in the embryo but not in the cell so to make in enter you need to apply a electric current that will move the DNA into the cell because DNA is charged and cells membrane is denature. Once is done you hope the DNA is inside and the next morning you can look under the microscope, taking the embryo out, if some cells express the gene and are fluorescents. With this method you can express many genes and target many things, is not easy to use because embryo can be very small and you really need to be calm and don't move to much, but with a bit of training you can succeed! Working on embryo need to do some tricky manipulation, electroparation in one off them, but some people even do transplant of somites or change the membrane under the embryo! More over just take an embryo out of the egg to clean it and put it on an appropriate plate to look at it under the microscope took me one week and many eggs to now succeed (most of the time!).
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