Mitochondria

Question 1

endosemiont system

Question 2

organelle biogenesis

Answer 2

included protein targeting, membrane assembly morphology, metility, replication, degradation, and inhetiace during cell division

Question 3

semi autonomous

Answer 3

• both mitochondria and chloroplasts
• organelle replication controlled by both nuclear genome and organelle genome

Question 4

mitochondria mophology

Answer 4

• double membrane
• outer mem - permiable porins
  -intermem - impermiable
• inner - high [H+]
  -matrix- aqeous interior

Question 5

mitochondria network

Answer 5

highly branched, long and interconnected series of tubules

Question 6

fission

Answer 6

1) ER tubules encircle mitochondria at future fission site and initiate constriction
2) DRP(mediated by lipid microdomain) recruited and assembled into helicases,
this is enriched by cardiolipin which interact at constriction cite
3) conformational change at ring

Question 7

fusion

Answer 7

1) outer membrane tethering
- mfn1 and mfn2
- bak and bax mediate binding
2) outer membrane fusion
- formation pf outer membrane lipid microdomains at sites of tethering
- phospholipase converts cardiolipin into phoporadic acid (inner to outer mem)
- phospatidic acid promotes curvature of outer mem during mrn fusion
3) OPAT
- mediate inner membrane fusion

Question 8

prohibition

Answer 8

• ensures OPA1-mediated fusion occurs only between different inner membranes
• prevents self fusion

Question 9

matrix targetinf sequnce

Answer 9

1)cytoplasmic molecular chaperons (HSP7) reconize protein synthesis on free ribosome in cytoplasem
- mitochondrial mRNA localization
mitochondria cloud
- resulting in mitochondria sythesis
2) at surface of mitochondion proteins matrix targettinf sequence recognized by Import recepot complex
- Tom 20, Tom 22
- general import pore
3) precursor protein passed from import receptor to general import pore in out mem
- mostly protein Tom4
- forms trans membrane channel
4) precursor protein goes through
5) general import pore
- adjacent inner membrane channel
- Tim 17, Tim 23, Tim44
general import pore and simmer membrane channel adjacent to each other at contact cite
matrix targeting sequence exits inner goes to out and is cleaved by matric processing proteases
- bond by matric HSP 70 (acts as motor)
- bind to Tim 44
6,7) cleaved protein in matrix folds without further assistance into final active config
or
required matric localized molecular chaperons and ATP hydrolysis

Question 10

mitochondria cloud

Answer 10

-minus encoding mitochondrial proteins often enrich in cytoplas, surrounding mitochondria
- mediated by RNA binding proteins
- resulting in mitochondria sythesis

Question 11

general import pore

Answer 11

accesory proteins serve as scafplding tp mediate precurer proteins transfer from import recpet togeneral import pore