Friday 3 - Drewes - Glia & myelin

Question 1

During the synthesis of myelin lipids, addition of what to a fatty acid allows it to combine with another fatty acid?

Answer 1

a serine group

Question 2

During the synthesis of myelin lipids, sugars are attached to the hydrophilic ends of two fatty acids that are joined. What is the most common sugar to attach in myelin lipids?

Answer 2

galactose

Question 3

instead of ester bonds in FAs in myelin, there are:

Answer 3

ether bonds

Question 4

what myelin protein(s) are/is in the CNS, but allmost absent from the PNS

vice versa?

Answer 4

PLP (ProteoLipidProtein) - in CNS

Po (Pzero protein) - in PNS
PMP - 22 - in PNS

Question 5

Function of MBP

Answer 5

holds cell membranes of the swirling myelin together, its on the innermost rung of the myalin swirl (called the intracellular membrane)

the protein itself is EXTRACELLULAR/EXTRAMEMBRANOUS

Question 6

Function of PLP

Answer 6

in CNS -

intramembrane protein that hold cell membranes of the swirling myelin together (by binding to other PLPs)

Question 7

Function of Po protein

Answer 7

in PNS

plays similar roll to PLP, but in PNS. spanns membranes and holds myelin cell membranes together

Question 8

What becomes oligodendrocytes in the brain

Answer 8

OPCs (oligocyte progenitor cells)

they make new oligodendrocytes in response to injury in the brain, as well as during development

Question 9

demyelinating disease vs

dysmyelinating disease

Answer 9

De - myelin is fine during development, but gets worse due to disease

Dys - myelin was never formed right to begin with (genitiaclly defective)

Question 10

what was the “cure” for adrenoleukodystrophy

Answer 10

lorenzo’s oil

synthesis of bad FA are blocked by this

Question 11

What happens in Charcot marie-tooth syndrome

Answer 11

muscles don’t have any stimulus, so they fade away.

PMP - 22 has been duplicated in the allele, so you have too much PMP - 22 (detect it via fluorescent in-situ hybridization)

demyelination and remyalination give rise to an onion looking axon in a cross section.

get less muscle in calves usually

Question 12

Why can you see white spots in the brain on MRI is someone with MS?

Answer 12

gliosis leads to fat deposits that show up brightly

Question 13

What do you have more of in MS patients on the White blood cells and the endothelium of the capilaries that allows the WBCs to get into the brain causing damage

Answer 13

VCAM-1 on the endothelium

alpha4beta1 on the T cell (making antibodies against this is a treatment for MS)

these proteins allow the WBCs to get into the brain

Question 14

name of antibody given to MS patients. what does it attach to

Answer 14

Natalizumab

attached to alpha4beta1 on T cells