Episode 5- A Day in the Life (in the Lab)

For me in the Wray lab, everyday is pretty close to the same (so long as there are sea urchins in stock). As soon as I get to the lab, I check on the sea urchins I injected the day before if I did injections. Then, I check the dry erase board to see if there’s anyone planning to spawn an urchin before 1 since any time after that is too late. If there isn’t anything written on the board, I go ahead and make the injection mixtures I’m going to be doing that day and set them on ice. Then, I grab the urchin tray and bring it to the urchin room.

Once I’ve spawned some eggs, I have to wash them several times to remove the jelly so the eggs don’t stick together and dirty the water. While waiting for the eggs to settle during the wash, I set up what I need to row the eggs on some plates. After the wash,  put the eggs in a glass dish, swirl them into the center, and place them under a microscope to begin collecting them.

Using a mouth pipette, I suck up some eggs and then blow them out gently onto a plate filled with sea water and PABA (Para-Aminobenzoic Acid) which keeps the eggs soft enough to inject. If done right, the eggs stick to the bottom and don’t roll around much from where they were placed. Then, I add some sperm to each plate and swirl them around to make sure the eggs get fertilized. Now, they’re ready for injection.

To set up for the injection, I take a needle and place it into a nozzle and place a plate on the microscope stage. After a minute or two of adjusting the needle and stage positions, I can see the needle and inject the fertilized eggs. Once injection is finished, all the plates are placed in a plastic case and into an incubator to develop.

Four to five hours later, I can take the embryos out of the incubator and begin transferring them to a 12 well plate. I use the mouth pipette again to select the glowing embryos since those were the ones injected and I move them to different plates depending on the treatment and how brightly they are glowing. Afterwards, all the plates go back into the incubator to develop more overnight. The embryos have to be transferred because spending too much time in the PABA makes them sick and develop poorly.

The following morning, I check the results and see how many of the embryos/larvae have developed and if there appear to be any significant differences in the way the injected versus control animals have developed. After that, I wash and throw out the plates and begin another batch of injections.

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