What is the Difference Between GAP and GEF?

🆚 Go to Comparative Table 🆚

The difference between GAP (GTPase-activating protein) and GEF (guanine nucleotide exchange factor) lies in their roles in regulating the downstream cell signaling of G proteins:

  • GEF: These proteins turn on signaling by catalyzing the exchange from G-protein-bound GDP to GTP, which activates the G protein. GEFs can activate multiple GTPases or be specific to a single GTPase, depending on the protein.
  • GAP: These proteins turn off downstream signaling of the cell after binding to a G protein. GAPs enhance the GTP hydrolysis reaction of the G protein, leading to the inhibition of the protein.

Both GAPs and GEFs are multidomain proteins that are regulated by extracellular signals and localized cues, controlling cellular events in time and space. Their roles are crucial for cellular function, as they help maintain the balance between active and inactive states of G proteins.

Comparative Table: GAP vs GEF

GAP (GTPase-activating protein) and GEF (guanine nucleotide exchange factor) are two factors that regulate the downstream cell signaling of the cell after binding to G proteins or GTPases. Here is a comparison table highlighting their differences:

Feature GAP GEF
Function Turns off downstream signaling of the cell after binding to G protein Turns on downstream signaling of the cell after binding to G protein
Action on G Protein Enhances the GTP hydrolysis reaction of the G protein Enhances the dissociation of GDP from the G protein

Both GAP and GEF play crucial roles in regulating downstream cell signaling and are essential for cellular function.