Table 10.1: Common covalent modifications of protein activity

Modification

Donor molecule

Example of modified protein

Protein function

Phosphorylation

ATP

Glycogen phosphorylase

Glucose homeostasis; energy transduction

Acetylation

Acetyl CoA

Histones

DNA packing; transcription

Myristoylation

Myristoyl CoA

Src

Signal transduction

ADP ribosylation

NAD+

RNA polymerase

Transcription

Farnesylation

Farnesyl pyrophosphate

Ras

Signal transduction

γ-Carboxylation

HCO_3

Thrombin

Blood clotting

Sulfation

3′-Phosphoadenosine-5′-phosphosulfate

Fibrinogen

Blood-clot formation

Ubiquitination

Ubiquitin

Cyclin

Control of cell cycle