“Do you know how a cell divides?… The answer is no. All biologists should say no”
-George von Dassow
Cell division is exceedingly complicated. I have spent the last week trying to wrap my head around it. The more I learn, the more I realize I don’t know. Apparently, I am not alone in this feeling. George von Dassow has been studying this very subject for years and still has questions about how it all works. Since I am jumping into a small part of his research on the subject for my REU, I will attempt to explain my little bit here.
Cell division involves many, many proteins which work together to form a contractile ring which pinches the cell into two parts each containing a single copy of the original cell’s duplicated DNA. Many of these proteins’ role in this process is not clearly understood. I will be focusing on the protein Anillin and its role in cell division for my project. This protein may have a regulating effect on cell division, keeping the cell from becoming too excitable while forming the contractile ring. To study this protein I will be using something called gene knockdown. Gene knockdown is a process by which we can artificially turn off specific genes in the cell by blocking the RNA instructions to make that specific protein. Using the micromanipulator I practiced with last week, I will be injecting starfish oocytes with morpholino antisense oligonucleotides (a segment of specialized RNA that will attach to the gene for Anillin on the cells mRNA), hopefully blocking the cell from being able to use those mRNA instructions to make the protein Anillin.
Then, I will fertilize these cells and see if the gene knockdown will cause anything abnormal about their division. From observing what happens to these cells I may be able to draw conclusions on the roll of Anillin during cell division.
Baby Watch 2017
The babies are growing up so fast! I have been diligently changing their tank watering and feeding them a healthy diet of algae. As promised, I have baby photos.
I also sacrificed and stained some Patiria larva to view them with the confocal microscope. The confocal is a powerful tool that creates beautiful and detailed images. By staining we are able to only view particular structures in the cells. We stained larva for nuclei (seen in blue) and actin filaments (seen in green). You can see a clear outline of the larva in blue because the cells on the outer surface are tightly packed together into a ciliated band.
We also used the confocal to view the image in several “slices” which I used to put together the video below.
See You Next Week!
Thanks so much for reading.
My name is Nicolle Koontz and I am from Grass Valley, California where I attend Sierra College. I am lucky enough to be working in George von Dassow's lab doing research on the cellular biology of starfish oocytes during mitosis. I am an information addict. I have to know how things work, how we know how those things work, and why they work the way they do. These sorts of questions have led me to major in Biology. As an REU intern I look forward to working in a state of the art lab with mentors and grad students who share in my joy of discovery while also building my skill set. I am so excited to dive into a project that can contribute to our collective scientific understanding of the world.