Mitochondria
TRNA's of MITO
1. Have fewer tRNAs than are used by the rest of the cell 2. Follow relazed pairing rules 3. Genetic code is also different from the rest of cell
Nuclear Respiratory Factor (NRF)
1. Is one transcription that is activated by AMPK 2. Stimulates the transcription of many mitochondrial genes
Mitochondria Genes
1. Evolved more rapidly than nuclear genes 2. Inherited by Non-Mendelian cytoplasmic inheritance (You get mito from mama) 3. The # of mito genes vary according to the energy needs of the cell
Activated Protein Kinase (AMPK)
1. Fuel sensor of cell 2. Alters the function of many proteins and the transcription of genes for compensation 3. Activated a. When the AMP/ATP ratio is high b. Starvation c. Increase in phospho creatine 4. Stimulates many aspects of energy metabolism
Mitochondria and its properties
1. Have their own a. Ribosomes b. DNA c. RNA d. Synthesize some of their own proteins
Cristae
1. Internal compartments formed by the inner membrane of the mitochondria 2. Studded with proteins including ATP synthase and a variety of cytochromes 3. Allows cellular respiration to occur
Functions of Mitochondria
1. Make ATP through Oxidative phosphorylation 2. Calcium Storage 3. Involved in steroid synthesis 4. Have in liver cells enzymes that detoxify ammonia 5. Cell death
Mitochondria may have originated from bacterium
1. Mitochondria have the same features found in bacteria. 2. This supports the idea that mitochondria may have originated as phagocytised bacteria.
Role of Mitochondria in program cell
A. Damaged mitochondria release Cytochrome C and several enzymes in the cytoplasm B. Cytochrome C activates Caspase-9, who activates other capases C. Capases destroy proteins and DNA leading to cell death d. Massive protein degradation, nuclear lamins, chromatin
Oxidative Metabolism of Nutrients creates a Protein Gradient used to make ATP
A. Nutrients imported into mitochondrion via VDAC B. Citric acid cycle generates hydrogen ions and electrons C. Electron transport chain; separates hydrogen ions from electrons D. Hydrogen ions accumulate in the intramembrane space E. Hydrogen ion flow through ATP synthase into a matrix generates ATP F. ATP leaves mitochondrion via VDAC
Sterioid Acute Respiratory Protein
1. Cholesterol is imported into the mito under STAR's influence 2. LDL binds to cholesterol and carries it across the membrane 3. Steroid synthesizing MITO have tubular cristae not prismatic
TOM & TIM
Transport Outer Membrane and Transport Inner Membrane 2. Import proteins into the matrix
Voltage Dependant Anion Channel
VDAC takes in-Pyruvates (Nutrients) VDAC releases-ATP+Hexokinase *Has a similar function to nuclear pore in the mitochondria
Lateral Sclerosis
1. Death of motor neurons due to mitochondria damage 2. Inherited form involves a misfolded enzyme called SOD that blocks VDAC
Superoxidase Dismutase
1.It is a misfolded enzyme SOD that blocks VDAC 2. Therefore less hexokinase and ATP is released from the cell
If you fail to repair mitochndrial DNA
1. Show early signs of aging
Mitochondrial Calcium Uniportter
1. Takes in calcium and stores it 2. Mito is a buffer region for calcium ions coming from the ER.
Mitochondria Transport
1. They travel on microtubules 2. In ion transporting cells mitochondria are located near basolateral cell membrane infoldings and provide locally needed ATP
Mitochondria Fuse and Divide
1. To form constantly changing tubular networks in most eukaryotic cells 2. Fusion and division normally counterbalance each other a. nutrients can manipulate it
When ATP becomes depleted in Mito
1. cells respond by metabolizing glycogen 2. Increasing glucose uptake 3. Increasing mito # and activity to produce more ATP