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SMP - MCP Exam 1 > Organelle Diseases > Flashcards

Flashcards in Organelle Diseases Deck (40)
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1
Q

What organelle is progeria due to?

A

Nuclear envelop

2
Q

What organelle is dyskeratosis congenita due to?

A

Ribosome

3
Q

Describe dyskeratosis congenita

A

Mutation of the dyskerin gene which is involved in ribosome biogenesis: abnormal skin pigmentation w/ tan-to-gray hyperpigmented or hypopigmented patches in a mottled or reticulated pattern

4
Q

Describe progeria

A

Premature aging in children leading to death linked to a mutation in the lamin A gene (messes up one of the parts of cell division)

5
Q

What organelle is cystic fibrosis due to?

A

ER

6
Q

Describe cystic fibrosis

A

Misfolding of the cystic fibrosis transmembrane regulator protein which is trapped in the ER and then degraded: deficit of this protein causes thick mucous in lungs

7
Q

What organelle is congenital disorder of glycosylation syndrome due to?

A

Golgi

8
Q

What was congenital disorder of glycosylation syndrome previously called?

A

Carbohydrate-deficient glycoprotein syndrome

9
Q

Describe congenital disorder of glycosylation syndrome

A

Rare defect of metabolism where glycosylation of tissue proteins is deficient (inability to charge mannose to prepare it for glycosylation) with causes cerebellar and cerebral atrophy and psychomotor retardation

Symptoms: failure to thrive and mental retardation

10
Q

What are lysosomal storage diseases?

A

50+ rare metabolic inherited diseases resulting from defects in lysosomal function

11
Q

What organelle is peroxisomal disease due to?

A

Peroxisome

12
Q

Describe peroxisomal disease

A

Neurological diseases that results from defects in biogenesis of peroxisomes or in enzymes in them

13
Q

What organelle is adrenoleukodystrophy (ALD) due to?

A

Peroxisome

14
Q

Describe adrenoleukodystrophy (ALD)

A

Disorder of peroxisomal fatty acid beta oxidation that results in the accumulation of very long fatty acids in tissues

15
Q

Describe cerebral adrenoleukodystrophy (ALD)

A

Progressive demyelination leading to vegetative state and death

16
Q

What organelle is mitochondrial myopathy due to?

A

Mitochondria

17
Q

Describe mitochondrial myopathy

A

Muscles exhibit “ragged red” fibers that contain accumulations of glycogen and neutral lipids
Symptoms: low energy, free radical production and lactic acidosis that result in muscle weakness, exercise intolerance, trouble with balance and coordination and seizures

18
Q

What organelle is albinism due to?

A

Cytoplasmic inclusions: Melanosomes

19
Q

Describe albinism

A

Lack of tyrokinase activity preventing melanin synthesis (pink eyes because reflect blood from back of iris)

20
Q

What organelle is Von Gierke disease due to?

A

Cytoplasmic inclusions: Glycogen

21
Q

Describe Von Gierke disease

A

Impaired breakdown of glycogen causes an enlargement of the liver

22
Q

What is another name for Von Gierke disease

A

Type 1 glycogen storage disease

23
Q

What organelle are lipid storage disease due to?

A

Cytoplasmic inclusions: lipids

24
Q

Describe lipid storage diseases

A

Inherited metabolic disorders where harmful amounts of lipids accumulate in cells and tissues which can cause permanent damage especially in the brain, PNS, liver, spleen, and bone marrow

25
Q

What is another name for the lipid storage diseases

A

Lipidoses

26
Q

What organelle is nemaline rod myopathy due to?

A

Cytoskeleton: microfilaments

27
Q

Describe nemaline rod myopathy

A

Congenital neuromuscular disorder that causes muscle weakness and results from mutations in the ACT1 gene which codes for alpha-actin
You can find rod-like inclusions (nemaline bodies) in the sarcoplasm of skeletal muscle fibers

28
Q

What organelle is ciliary dyskinesia due to?

A

Cytoskeleton: microtubules

29
Q

Describe the 4 types of ciliary dyskinesias

A
  1. Absent inner dynein arms
  2. Radial spoke defect
  3. Absent central pair
  4. Absent inner and outer dynein arms
30
Q

What do ciliary dyskinesias predisposes patients for? More common in what type of pts?

A

Ineffective ciliary mvt impairs mucociliary clearance: recurrent chest infections and these are more common in smokers

31
Q

What organelle is epidermolysis bullosa simplex due to?

A

Cytoskeleton: intermediate filaments

32
Q

Describe epidermolysis bullosa simplex

A

Increasing blistering related to friction (shoes/socks) resulting from an autosomal dominantly inherited defect in keratins 5 and 14

33
Q

What cell junction is celiac disease due to?

A

Zonula occludens

34
Q

Describe celiac disease

A

Damages the lining of the small intestine and prevents it from absorbing parts
of food that are important for staying healthy. Can be caused by Zonulin, a zonula occludens toxin
secreted by the pathogen Vibrio cholera. Zonulin breaks down tight junctions, increasing their
permeability between cells of the wall of the digestive tract.

35
Q

What cell junction is bacteriodes fragilis due to?

A

Zonula adherens

36
Q

Describe bacteriodes fragilis

A

Bacterium produces a toxin (B. fragilis enterotoxin) that alters zonula
adherens function, so compounds leak between cells. Associated with diarrheal diseases.

37
Q

What cell junction is arrhythmogenic right ventricular cardiomyopathy/dysplasia due to?

A

Desmosomes

38
Q

Describe arrhythmogenic right ventricular cardiomyopathy/dysplasia

A

Heart muscle disease
characterized by life-threatening arrhythmias and increased risk of sudden heart failure. Caused by
mutations in genes encoding desmosomal proteins.

39
Q

What cell junction is Charcot-Marie-Tooth X disease (CMTX) due to?

A

Gap junctions

40
Q

Describe Charcot-Marie-Tooth X disease (CMTX)

A

Point mutation in the connexin-32 gene
on the X-chromosome. The connexin-32 protein is expressed in Schwann cells that wrap around
nerve axons, so CMTX affects components of the nervous system, which in turn affects muscle
function. A typical feature includes weakness of the foot and lower leg muscles. Foot deformities,
such as high arches, are common due to weakness of the small muscles in the feet.