lecture 5 Flashcards
vesicles at cisterna
- tips fuse or pinch off
three types of golgi?
cis, medial, trans
COP2 vesciles
RER to Golgi uses these vesicles for anterograde transport
COP1 vesicle
cis-Golgi to RER using retrograde transpor
clathrin veicles
TGN/PM to late endosomes
GTP binding proteins
- control assembly and disassembly of cop 2 coat proteins and docking vesicles to membrane
DXE
- used by certain cargo membranee proteins sorting signal that is recognized by cop 2 protein
Do golgi sub-compartments differ in the enzymes they contain
- yes they might have glycosidases or glycosyltransgerases
Gycosyltransferases
Add sugars
Glycosidases
Removing sugars
Cis golgi enzymes
Glycosidases
Medial golgi enzymes
Transferases and Sudanese
Trans folgi
- transferases
Where does sugar addition to proteins start
In eR, but continues elsewhere
Why are glycosulations important
Important for sorting proteins to the lysosome
Trans golgi network
Must decide if a protein si going to be secreted or go to lysosome.
Lysosome
Contains acidic hydro lasers that function at low pH that divest problematic material
What is the order of golgi sub compartments starting from ER
- cis golgi
- medial golgi
- trans golgi
Clathrin
It is a three legged protein
How does clathrin cause physical deformation of membrane to make it round
Assembles with other clathrin structures to form a soccer ball structure
How are cytotoxic proteins and organelles degraded
- by their enclosure in a double membrane vesicle (an autophagosome) which fuses with lysosomes
Autophagosomes
- a double membrane vesicle
what types of proteins have KDEL sequences
- luminal proteins including chaperons (e..g, BiP) and lectins (like calreticulin) have KDEL sequences
triskelion structure
- heavy chain, light chain, binding site for assembly partilces
