What happens when you remove cells essential for development? How can cells detect changes around them in order to change their gene expression. Why are these questions even important?
Ettensohn and McClay show that the removal of skeletal cells from the sea urchin embryo causes non-skeletogenic mesoderm (NSM) cells to transfate in order to take on the role of the missing skeletal cells. Ettensohn et al. showed that a skeletal cell specific gene is expressed during the process of transfating because it plays an important role in the gene regulatory network in the skeletal cell lineage.
However, we still do not understand exactly how the skeletal cells suppress NSM transfating. Therefore, in the McClay lab, I work on a project to explore the question of how the embryo recognizes and regulates cell loss in the sea urchin, Lytechinus variagatus. In order to do so, I will be performing in situ hybridization experiments on a list of candidate genes expressed in skeletal cells in order to verify their expression. I have already designed and ordered primers that will be used to clone genes through polymerase chain reaction (PCR) of the sea urchin’s cDNA. The genes will then be used to synthesize RNA probes which will be used for the in situ hybridization experiments.
I will also be using drug inhibitors to see if there is ectopic (abnormal) cell reprogramming in the sea urchin embryo. This will be done by treating developing embryos at different time points with a drug inhibitor and performing in situ hybridization experiment. By inhibiting certain signaling molecules, I would be able to see whether or not the signaling molecule plays a role in the embryos recognition of skeletal cell presence.
These are my current aims for the summer, but I already have so many more questions popping up from preliminary data and reading the literature that I hope will guide me in the coming weeks and into the future.