Lecture 12 Overview of Protein Sorting

Question 1

What is the Nucleolous

Answer 1

region of the nucleus where rRNA and tRNA is transcribed and processed

Question 2

What is a snoRPS

Answer 2

modify rRNA’s and cleave

Question 3

What are sno RNAs?

Answer 3

RNA components of snoRPS

Question 4

What is the nuclear pore complex (NPC)

Answer 4

an opening to move between the nucleus and cytosol

Question 5

What are nucleoporins?

Answer 5

proteins that comprice the NPC

Question 6

What are Karyopherins

Answer 6

proteins that carry cargo through NPC

Question 7

What are importin/exportins

Answer 7

2 types of karyopherins in/out of the nucleus

Question 8

What is ran

Answer 8

A small GTPase

Question 9

What do GTP and GDP do?

Answer 9

ran-GTP binds importin causing it to release its cargo. Then exits the nucleus.

ran-GAP causes ran to hydrolyze GTP into GDP. This makes ran release importin. Ran GDP then re-enters the nucleus itself causing ran to unbind from GEF and bind to GTP

this is all really retardedly confusing and we wont even be asked about this

Question 10

How do things get out of the nucleus?

Answer 10

ran-GTP binds importin, which has bound cargo containing an NES. This then causes it to move out of the nucleus. Ran-GAP then turns GTP to GDP and makes ran release exportin which also causes it to release the cargo. Then ran-GDP casts the spell “get-da-fuck-outa-here” and so ran-GDP magically goes back into the nucleus again