Project 451020

Stem cells are very important for the growth and maintenance of a number of our tissues. Curiously, they do not like to divide and only do so when signals instruct them to repair damage or, for whatever reason, to make new tissue. If these cells lose the ability to restrict their proliferation the results can be devastating and may be at the heart of many forms of cancer. We use a simple genetic model to understand how genes communicate signals to the stem cells that make up our germ line...the cells that make our gametes; our sperm and eggs. This cell lineage is what biologists refer to as the immortal lineage because cells in this tissue transmit genetic information between generations. We have found that a series critical genes can communicate signals to these special stem cells to stop dividing and prepare for tough times. This may occur through interesting intermediates called small RNAs that act kind of like hormones. In this proposal we aim to shed more light on how these instructions move from one cell to another so that signals that are sensed in one cell type (the nervous system) are appropriately transmitted to the germline stem cells to tell them to stop dividing and prepare for what may be a long period of duress-due to starvation for example. This is important to protect the genes in the sperm and eggs so that the information that they will transmit into the future will remain complete and accurate.