Thread: Stem Cell to Specific Cell question

Stem cells at one point in time turn into specilized cells, how do they know what specialized cell to turn into? Every stem cell has every trait of that organism, so it can be transformed into any specialized cell, but how does the stem cell know what genes to "turn on"? For example, how does a stem cell know to "turn on" the lung cell genes when in the lungs rather than just "turning on" the skin cell genes? What in the lungs causes the stem cell to turn into a lung cell? If you say the surrounding cells, well it all had to start somewhere...

It's not just about the Chromosomes, RNA and DNA...I'm not sure if they know what makes one group of cells all of a sudden decide "lets make a heart!", but I'm pretty sure it is somewhere in the proteins. Now that the human genome has been mapped, we know that there are many more factors to what happens during the formation of embryos than we thought. Proteins play a large part in this and they are just scratching the surface of understanding a small amount of these protein chains. It will be a much longer, more complex endeavor than mapping the genome, but with today's computers it hopefully will not take too long...

Raymond, it sounds like what you are really interested in is embryogenesis. A quick search with that term will get you lots of information. As SuperNatendo says there are a lot of complicated mechanisms going on to ensure that the right cells form in the right places. Cells in a growing embryo take cue from their position relative to the axis of cell division, from contact with other cells in the embryo, etc.

Environment and history.