Lecture 30: Mitochondrial Disease

Question 1

Recall about mitochondrial energy generation.

Answer 1

Question 2

Mitochondria are under the dual genetic control of both _________ and _________

Answer 2

Mitochondria are under the dual genetic control of both nuDNA and mtDNA.

Question 3

Describe mitochondrion.

Answer 3

Question 4

Describe mtDNA.

Answer 4

• Multiple copies of circular mtDNA inherited from mother.
• mtDNA is packaged by mitochondrial transcription factor A (TFAM) into mitochondrial nucleoids (basic organisational unit of mtDNA).
• Mitochondrial nucleoids control the transmission and expression of mtDNA.
• ∼16 kb long Thousands of copies Encodes 37 genes:
• 13 (out of 89 subunits) essential subunits of the OXPHOS.
• 2 rRNAs and 22 tRNAs, for intramitochondrial protein synthesis of OXPHOS

Question 5

Recall the role of TFAM in the regulation of mtDNA.

Answer 5

Question 6

_______________ and _______________ regulate TFAM binding to _________.

Answer 6

Question 7

Recall the effect of TFAM in mitochondrial diseases.

Answer 7

Question 8

Recall mitochondrial energy diseases.

Answer 8

Question 9

How common are OXPHOS disorders?

Answer 9

Question 10

Differ between adult-onset and childhood-onset mitochondrial disorders.

Answer 10

Question 11

Recall how mitochondrial disorders are complicated

Answer 11

Question 12

Differ between heteroplasmy and homoplasmy.

Answer 12

Question 13

Recall the diagnosis method of mitochondrial disorders.

Answer 13

Question 14

Recall the MitoExome Strategy

Answer 14

Question 15

Recall Acquired mtDNA mutations in ageing and cancer

Answer 15

Question 16

Describe Leigh’s Syndrome.

Answer 16

Question 17

Recall the symptoms of Leigh Syndrome.

Answer 17

❑ Signs and symptoms usually progress rapidly.
❑ Early symptoms may include poor sucking ability; loss of head control and motor skills; loss of appetite; vomiting; and seizures.
❑ As the condition progresses, symptoms may include weakness and lack of muscle tone; spasticity; movement disorders; cerebellar ataxia; and peripheral neuropathy.
❑ Complications can lead to impairment of respiratory, heart and kidney function.
❑ While life expectancy depends on the cause of Leigh syndrome in each person, most do not survive past mid-childhood or adolescence.

Question 18

Recall Leigh Syndrome Diagnosis

Answer 18

Question 19

Recall Leigh Syndrome Causes

Answer 19

Question 20

Recall Leigh Syndrome Inheritance.

Answer 20

Question 21

Recall treatment for Leigh Syndrome.

Answer 21