Sorting 1

Question 1

Name the three topological compartments.

Answer 1

1) Nuclear/Cytosol
2) Organells of secretory and endocytic pathways
3) Mitochondria

Question 2

Which transport mechanism communicates unidirectionally?

Answer 2

TM or Transmembrane transport

Question 3

Most topological compartments communicate via ___ and ___.

Answer 3

Budding and fusion

Question 4

How do proteins communicate?

Answer 4

Sorting Signals which are a stretch of 15-60 A.A found at the N, C terminus or middle of the protein sequence.

Question 5

What is a signal patch?

Answer 5

When protein sequences of sorting signals form their tertiary structure creating a folded congregation.

Question 6

What removes the protein signal once it reaches final destination?

Answer 6

Signal Peptidase

Question 7

Signal sequence of “import into nucleus”

Answer 7

Heavy in Lys-Arg sequence

Question 8

Signal sequence of “import to mitochondria”

Answer 8

Positively charged and hydrophobic A.A

Question 9

Signal sequence of “import to ER”

Answer 9

Mostly hydrophobic A.A

Question 10

Signal sequence of “return to ER”

Answer 10

KDEL

Question 11

NPCs are _____ made of ____ shaped, almost like a ____

Answer 11

Nuclear Pore Complexes, nucleoporins, octagonal shape, baskets.

Question 12

NPC signals are facilitated by ___

Answer 12

Fibrils off the NPC

Question 13

NLS are ____ that direct molecules to the nucleus rich in ____ since they are part of nucleus

Answer 13

Nuclear Localization Signals, Lys-Arg

Question 14

NPCs allow transport via ____ and ____

Answer 14

Passive Diffusion and Facilitated Transport

Question 15

NLC allow ____ transport

Answer 15

selective

Question 16

Describe how signals come into the nucleus from cytoplasm

Answer 16

The Nuclear Localization Signal (NLS) and Nuclear import receptors (NIR) bind to either directly or indirectly on the periphery of the nucleus. They travel through Fibril Nuclear Pore Complexes It brings the signal into the nucleus and the NIR goes back into the cytoplasm

Question 17

Fibrils are made of

Answer 17

FG (phenylalanine glycine) repeats

Question 18

Just like nuclear import process, nuclear export is conducted by NES or ____ that bind to ____ to allow transport to cytoplasm

Answer 18

Nuclear export signals, nuclear export receptors

Question 19

In the Cytosol Ran GAP convert G– into G–

Answer 19

GTP–GDP

Question 20

In the Nucleus, Ran GEF converts G– into G–

Answer 20

GDP–GTP