LECTURE 6 Flashcards
Mitochondrial disease
Can be Fatal
prokaryote bacteria have what structures (organelles)
1- Cell wall
2- Plasma membrane
3-Ribosomes
4- FREE DNA
Animal cell vs plant cell
Both have : 1- mitocondria 2- plasma membrane 3- ribosomes 4- Golgi apparatus 5- Endoplasmic Reticulum 6- Nuclear envelope and nucleus
Plants have
1- chloroplasts(with thylakoid membrane)
What is contained within mitochondria and chloroplast
Both: 1- Outer membrane 2- Inner membrane 3- DNA 4- Ribosomes
mitocondria:
1- Matrix
Chloroplast:
1- stroma
2- grana
3- Thylakoid membrane (additional third membrane)
Mutations within mitocodnrial genome?
fatal, mitocondrial disease
Why have a lot of the mitochondria and chloroplast genome been incorporated into the nuclear genome?
to allow the nucleus to have control over the genes and expression of them
Endosymbiosis
cynobacterium (chloroplast) and proteobacterium (mitochondria) entered cells (billions of years ago) via endocytosis. A mutalilistic relationship was developed and both bacterium evolved to become chloroplast and mitocondria.
size of chloroplast genome?
80 000, to 600 000 base pairs long.
shape of chloroplast genome
circular double stranded, highly coiled but no histone proteins
chloroplasts contain? NOT STRUCTURE
rRNA’s, tRNA’s, ribosomal proteins and genes involved in photosynthesis
Most abundant protein on earth
RubisCo
Gene arrangement in chromosomes? (pros)
operons, gene order of many gene are shared with E.coli
Volume of coding vs non coding DNA in chloroplasts?
lots of non coding
Name 3 related characteristics between eubacteria and chloroplasts?
- antibiotics which inhibit protein synthesis in eubacteria so also in chloroplasts
- Same proteins are involved in transcription and translation
- Genes transcribed in groups (operons)
mitocondrial and chloroplast Phylogenetics use?
can track common ancestors and how close related two species are by looking at mitocondrial and chloroplast DN
which evolves more slowly
A) chloroplast DNA
B) Nuclear DNA
C) mitochondrial
a
Mitochondria containing copies of the genome?
several copies
size of mitochondrial genome, unique as?
6kbp’s to millions of base pairs. VERY LARGE RANGE
Histone proteins in the mitochondrial genome?
similar
how many proteins found in the mitochondria ?How many coded for by the nucleus?
40/900
Number of genes coded for within the mitochondrial genome? What they code for?
40-50 genes. Proteins important for respiration, oxidative phosphoralation, transcription, translation, RNA processing, import of proteins into the cell
mitocondrial ribosomes?
Different to that of bacteria and eukaryotes
Mitochondria variation of DNA between TAXA plant and animal cells?
- Animals and fungi: single, coiled circular DNA molecule
- Plants: multiple, circular DNA molecules
- Some species contain mitocondria with a single linear DNA molecule
Mitochondrial gene expression variance between TAXA ?
- full strand transcription
- operons
- single gene transcription
Do fungi and plant mitochondrial DNA contain introns
yes
size of mitochondrial genome
16 000
how much of the mitochondria genome is coding ?
90%
How many promotes per strand?- Mitochondrial genome
1
Yeast mitochondrial genome size?
6X larger
2 characteristics of yeast mitochondrial genome?
UTR, intergene spacers, alot of introns
Plant genome tandem repeats ?
Large quantity
Respiration dangerous by product ? How does this increase?
free radicals, damage lipids and proteins, which contributes to ageing. As age increases mitochondrial function efficiency also decreases, which increases the production of free radicals
Most affected tissues by mitochondrial disease ?
oxygen hungry tissues- muscle and liver, pancreas, nervous system (brain)
Mitocondrial segregation leads to?
homoplasmy hetroplasmy of mutated and wild type mitochondria as mitosis occurs.
Way in which mitchondrial disease can be treated before a baby is born?
Enucleate an egg in which has the risk of mitochondrial disease, insert into healthy egg. IVF and insert into mother where the baby is born
