So in the CNS system, besides neurons, we also have other cell types, astrocytes, microglias, oligodendrocytes. Oligodendrocytes can make the myelination and defect in myelin proteins disrupt conductions of nerve signals. This is the oligodendrocytes, making myelination around the axon. So, the picture here, the middle part is the axon. And then the dark part around it is the myelin sheet, made by oligodendrocyte cell. So as one mentioned, the axon is in the middle, and then oligodendrocyte, or Shwan cell, grow longer and longer, and then make the wrap around the axon, so, eventually, make myelin sheet. If some myelin protein is deleted, then we'll have very severe phenotype. One transgenic mice is called a shiverer. So, the shiverer is the partial deletion of myelin basic protein. The shiverer phenotype is the mice will shiver all the time. So it's called a shiverer. And it cannot work steadily in the surface. So if we put back this myelin basic protein, we can partially rescue the phenotype of the shiverer. So the myelin sheet, this is wild type. The dark part is the myelin sheet. And then the middle picture is from the shiverer mice, so you can see the myelin sheet are almost gone in this mice, and about putting back MBP, this protein, myelin basic protein, we can partially rescue the myelin sheet, but not as good as wild type. So in human, we can also have diseases related to myelination. In human, there's a disease called Charcot-Marie-Tooth disease, so the Charcot-Marie-Tooth disease is the duplication region happened in the myelin basic protein. So, in this picture, the left part is the normal allele, and then the right part is the duplication happened within the MBP protein. So in the Charcot-Marie-Tooth, this isn't a normal wild type. And so, in the Charcot-Marie-Tooth, the myelin sheet get thinner, so the patient show the instability in the movement. So the mutations in the MBP, or myelin basic protein, can produce, can induce the disease in the myelin sheet.