Question

1. What are some of the proteins that may be targeted by the immune system that could lead to myelin degeneration?  What roles do these proteins play in the production and maintenance of myelin?

Answer 1

A)Multiple sclerosis (MS) is a neurodegenerative demyelinating, . MS plaques contain both CD4+ and CD8+ T-cells and susceptibility is linked to immune response genes, suggesting that MS occurs when autoreactive T-cells enter the central nervous system (CNS) and attack cells expressing myelin antigens. Myelin basic protein (MBP) is one likely target: for these T-cells because it is an abundant protein in the myelin sheath.

T cells from the body's own immune system attack and destroy the myelin sheat.The body's immune system T cells attack the myelin sheath that protects the nerve fibers. The T cells either partially or completely strip the myelin off the fibers, leaving the nerves unprotected and uninsulated. The nerves are not as able to pass messages from the brain to the other body parts. The messages the nerves try to send are delayed or distorted and the messages the brain receives may be misinterpreted.

b)Myelin basic protein (MBP) and the proteolipid proteins (PLP/DM20) are the two major myelin proteins in the CNS. Myelin basic proteins are found on the cytoplasmic side and play a role in the adhesion of the internal leaflets of the specialized oligodendroglial plasma membrane.

Proteolipid protein PLP is a hydrophobic integral membrane protein that accounts for about 50% of the protein content of adult CNS myelin. The PLP gene encodes a 276-amino acid polypeptide with five strongly hydrophobic membrane-spanning domains that interact with the myelin lipid bilayer, and contributes to compact, multi-lamellar myelin formation.

Myelin basic protein (MBP) is a protein thst is  important in the process of myelination of nerves in the nervous system. MBP maintains the correct structure of myelin, interacting with the lipids in the myelin membrane.