Yamashita laboratory studies the mechanisms of asymmetric cell division using Drosophila male germline stem cells as a model system. During asymmetric germline stem cell division, these stem cells precisely orient their division plane with respect to the source of signals that dictate stem cell identity, such that the division will create with two daughter cells, one with the access to the signal and the other without. This asymmetric exposure to signals generate asymmetric cell fates (stay as stem cells vs. initiate differentiation). Our rising area of interest is satellite DNA repeats, which have been considered as genomic junk: our recent studies showed that satellite DNA is a critical constituent of eukaryotic chromosomes enabling encapsulation of the full complement of chromosomes into a single nucleus.
Our operational philosophy is to be guided by curious observations that cannot be explained within the existing paradigm, and by seeing the answer to explain these observations we aim to discover unappreciated biological mechanisms.