Mitochondrial genome Flashcards
What are the 4 functions of mitochondria?
β Produce ATP
β Haem synthesis
β Neurotransmitter synthesis
β Nucleotide synthesis
What does mitochondrial DNA look like?
β Double stranded circular molecule
What does mitochondrial DNA consist of?
β Heavy and light strand
How many genes does a mitochondria have?
β 37
What are the mitochondrial genes for?
β 13 oxidative phosphorylation protein subunits
β 22 tRNAs
β 2 ribosomal RNAs
Does a mitochondria have introns?
β no
What is a D loop?
β A non coding region where replication and transcription are initiated
How are mitochondria inherited?
β Maternally with no recombination
Which of the OXPHOS proteins is not coded for by mitochondria?
β succinate dehydrogenase
How is mtDNA packaged?
β Nucleoids
How are nucleoids arranged?
β one or two copies of mtDNA per nucleoid
What acts as a histone protein in mitochondria?
β TFAM (transcription factor A)
Where does mtDNA replication start?
β Origin of heavy strand (Oh)
Where does mtDNA transcription start?
β Heavy strand promoter and light strand promoter
What are the exceptions to the universal genetic code in mitochondria?
β AUA and AUG code for methionine (isoleucine in nuclear DNA)
β UGA codes for tryptophan (stop codon in nuclear DNA)
βAGA and AGG are stop codons ( arginine in nuclear DNA)
What are the haplogroups of mtDNA?
β M
β N
β H
β L0-L3
What is the most common haplogroup in europe?
β H
Why can mtDNA subdivide humans into discrete haplogroups?
β It does not recombine
Describe the origin of mitochondria
β a primitive eukaryotic cell ingested bacteria
β the bacteria helped the cell become more complex
β all bacterial DNA transferred to nucleus
β remnant of DNA is mtDNA