Nerve cell growth. Fluorescent light micrograph of neurons (nerve cells, red) in culture with the neural stem cells (blue) that they originated from. The stem cells have been dyed for nestin, an intermediate filament (IF) protein, and the neurons have been dyed for beta-tubulin III, one of the proteins that make up microtubules. IFs and microtubules are part of the cell's cytoskeleton, which is responsible for intracellular transport, cell structure and motility. Stem cells are unspecialised cells that can differentiate into a number of different cell types. Neural stem cells can differentiate in to neurons or support cells. Neurons are responsible for passing information around the central nervous system (CNS) and from the CNS to the rest of the body.