Packaging, Transcription And Translation Of mtDNA Flashcards
How is mtDNA packaged?
There are no histones
Packaging proteins (TFAM in humans, Abf2 in yeast)
What is the name of the packaging protein in humans?
TFAM
Describe the experiment which discovered the bending of DNA by TFAM using fluorophores
FRET - two ends of DNA labelled with different fluorophores (donor and acceptor)
Fluorophores only both get excited in close proximity, TFAM bends DNA and both fluorophores excited
Describe the plasmid experiment investigating TFAM
Mitochondrial DNA expressed in a plasmid, purified TFAM from recombinant expression, electron microscopy
When conc. of TFAM is increased the compaction of DNA increased
What did the optical tweezers experiment with TFAM show
A single molecule of TFAM needed to compact DNA, at 30 bo intervals (or 16)
How many different mRNAs are produced from mtDNA?
13
Complex 1 (7), 3, 4, ATP synthase
How many different tRNAs are produced by mtDNA?
22
How many rRNAs?
2
12 S and 16 S
What is an isoacceptor?
A tRNA that is for the same amino acid (only leucine and serine in mtDNA)
What are the two control regions in mitochondria called?
D loop and control region
What is special about the D Loop?
It is a triple stranded DNA region in the non-coding area and is the site of initiation of transcription and replication
What helps form the triple stranded DNA region?
7 s DNA
Where is the origin of replication?
191
What are the names of the two transcripts?
Heavy (HSP) and light (LSP)
Why is the heavy strand so called?
It has more purines
