Vesicular Transport IV

Chapter 13

3 possible fates of receptor proteins in an epithelial cell

opiodreceptorgreen

transferinred

Low Density Lipoprotein particle transports cholesterol in the blood

1500 cholesterol molecules esterified to long chain fatty acids in oneparticle

Normal LDL receptors facilitate transport of cholesteryl esters in clathrin coated vesicles

Defective LDL receptor protein causes high levels of blood cholesterol and heart disease

cholesterol is releasedin lysosome

Blood Flow is not restricted until 70% of artery is blocked

Formation of plaque

Formation of plaque

Plaque formation in artery

Formation of liposomes beneath endothelial layer

Foam Cell with lipid storage bodies

Plaque

Plaque formation in rat aorta

Severe atherosclerosis of the aorta.

Storage diseases

Cholesteryl ester storage disease

Membrane bound granules filled with lipids

Cholesterol ester storage disease

Hurler disease

Hurler disease is a lysosomal storage deficiency

Symptoms of gargoylism

• Stunted Growth

• Mental Retardation

• blindness

• deafness

• heart and muscle dysfunction

Two ways for some lysosomal proteins to end up in lysosome

3 best understood protein sorting pathways in the trans Golgi network

Hurler disease can be treated by adding lysosomal enzyme to blood stream

Alpha-1-antitrypsin deficiency

Normal protein export from the ER to Golgi

In alpha-1-antitrypdin deficiency export from ER does not occur

Alpha-1-anitrypsin accumulation in ER

Glycoprotein accumulation in liver cells

Globules of alpha-1-antitrypsin in liver cells

Failure of phagosomes and lysosomes to fuse

Mycobacterium tuberculosis releases sulfatides

3 pathways to degradation in the lysosome

Yeast in phagocytes stained with acridine orange become fluorescent as phagosomes fuse with

lysosomes

Sulfatides prevent fusion of phagosomes with lysosomes

two toxoplasma in phagocyte

1

2

lysosomes