Protein Post-translational Modifications

Question 1

What determines where a protein goes once being produced at the ribosome?

Answer 1

Signal Sequencing of amino acids

Question 2

Components of a generic protein translocator

Answer 2

Chaperone protein
Receptor on membrane
Translocon

Question 3

What is one of the key protein modifications? and where does it occur initially then finalised?

Answer 3

N-linked glycosylation

Initially in ER then finalised in the Golgi

Question 4

Why wont you see gylcosylation in bacteria?

Answer 4

They dont have a Golgi apparatus

Question 5

What does a polyubiquitin chain on Lysine target?

Answer 5

Targets a a protein for degradation

Question 6

What is O-linked glycolysation important in?

Answer 6

Neurodegeneration

Question 7

Phosphatase and (1) are used in protein phosphorylation

Answer 7

Kinase

Question 8

Example of active and inactive protein after phosphorylation

Answer 8

Activate- CDK2

Inactivate- Src

Question 9

How many Lysine are attached to Ubiquitin?

Answer 9

7

Question 10

How do you amplify a signalling pathway?

Answer 10

Increase concentration of ligand or amplication of signal

Question 11

Diffeerence between positive and negative feedback

Answer 11

Positive amplifies response of enzymes

Negative dampens response of enzymes

Question 12

Autotune regulation of somastatin is an example of what type of feedback system?

Answer 12

Negative Feedback

Question 13

What is the enzyme that catalyzes the splitting of PI(4,5)P2 into two second messenger molecules?

Answer 13

Phospholipase C

Question 14

What is the function of APC/C in ubiquitylation? and how does it function?

Answer 14

Its and E3 ubiquitin ligase
Transfers ubiquitin onto substrate proteins and in many contexts protein ubiquitylation targets that protein for protein degeneration.