Lecture 9- Nuclear Import & Export Flashcards
How do nucleotides enter the nucleus?
They enter the nucleus through diffusion since they are small enough
Test of discovery experiment
Bases upon observing a process
Test of necessity experiment
If you remove something, does the process still occur?
Test of sufficiency experiment
If you add something does the process now occur?
Nuclear localization signal (NLS)
Attaches to the protein to be imported
Not a protein, it I a protein domain
Why do you have to do test of necessity first?
It is easier to do and you don’t have to do the test of sufficiency if it is not necessary
What is required for nuclear import?
Nuclear localization signal (NLS)
Import in proteins
Importin proteins
Associate with both NLS and nuclear pore
Binds to the cargo with NLS and goes inside the nucleus
What is required for nuclear export?
Nuclear export signal (NES)
Export in proteins
Nuclear export signal (NES)
Attaches to the cargo inside the nucleus
Export in proteins
Associate with NES (or RNA directly) and nuclear pore
Affinity for nuclear pore of importin is
Always high or always low
Always high
Affinity fir nuclear pore of exportin is
Always high or always low
Always high
Affinity for cargo of Importin is
__ in cytosol and __ in nucleus
(High or low)
High in cytosol and Low in nucleus
Affinity for cargo of Exportin is
__ in nucleus and __ in cytosol
High or low
High in nucleus and Low in cytosol
