The delivery of newly synthesized protein to their proper cellular destination, usually referred to as protein targeting or sorting.
The mode of protein transport depends chiefly on the location in the cell cytoplasm of the polysomes involved in protein synthesis.
There are two modes of protein sorting:-
1) Co - translational Transportation.
2) Post - translational Transportation.
3. Introduction -
The delivery of
newly synthesized
protein to their
proper cellular
destination, usually
referred to as
protein targeting or
sorting.
4. Modes of protein Sorting -
The mode of protein transport depends chiefly on
the location in the cell cytoplasm of the polysomes
involved in protein synthesis.
There are two modes of protein sorting:-
1) Co - translational Transportation.
2) Post - translational Transportation.
5. Co – Translational Transportation
Protein synthesized on membrane bound polysome
being to enter the endoplasmic reticulum as they are
being synthesized called Co-Translational
transportation of protein.
In this process some organelles are involve given
below-
1)Endoplasmic reticulum
2) Golgi complex
3) Lysosome
15. Post-Translational transportation-
Most proteins are cotranslationally translocated, some are
translated in the cytosol and later transported to their
destination. This occurs for proteins that go to a
mitochondrion, a chloroplast.
This process is called Post-Translational transportation.
1) Mitochondria
2) choloroplast
3) Peroxisomes
17. Chloroplast-
Figure :-
Import of rubisco small (S) subunits into the chloroplast
stroma and the assembly of small and large (L)
subunits into the active rubisco enzyme
18. Figure :Two of the four known pathways
for transporting proteins from
the cytosol to the thylakoid lumen
20. Importance of protein sorting-
•The delivery of the newly synthesized protein to there correct
destination is most important task.
•ER are assists protein in correct folding chaperones and protein
processing enzymes in the ER lumen.
•The important role of the ER is to identify misfolded protein,
mark them, and divert them to a degradation pathway.
•The Golgi apparatus is thus involved in the processing the broad
range of cellular constitute that travel along the secretory
pathway
21. Reference-
The cell ,a molecular approach,M.Cooper
&Geoffrey,2006
The cell and molecular biology,Lohdish,2nd edition