What type of protein makes up nerve cells?

Answer 1

There's no single protein that makes up any cell type. Nerve cells, like every cell, have all the basic proteins for structural integrity and basic functions (like actin and myosin). You might be thinking of myelin, the protein component of the myelin sheath. The myelin sheath is made up of membrane processes from nearby cells wrapped around the axons, so it has a significant lipid component as well.