Caspases western blotting assay is also used to detect apoptosis

TLS Online TPP Program

#Id: 9634

#Unit 4. Cell Communication and Cell Signaling

The GAP for RAS (called a RAS-GAP) works by inserting one of its arginine side chains into the Ras active site, thus stabilizing an intermediate in the

hydrolysis reaction.

TLS Online TPP Program

#Id: 9635

#Unit 4. Cell Communication and Cell Signaling

Constitutively active Ras proteins (RasD) 

Replacement of the normal glycine 12 with any other amino acid (except proline) blocks the functional binding of GAP proteins and in essence “locks” Ras in the active GTP-bound state.

TLS Online TPP Program

#Id: 9636

#Unit 4. Cell Communication and Cell Signaling

Activated RTKs and cytokine receptors to activate Ras, by two cytosolic proteins — GRB2 and Sos

TLS Online TPP Program

#Id: 9637

#Unit 4. Cell Communication and Cell Signaling

GRB2 is an adapter protein, serves as a link, or scaffold, between the activated receptor and Sos

TLS Online TPP Program

#Id: 9638

#Unit 4. Cell Communication and Cell Signaling

Sos is a GEF that catalyzes conversion of inactive GDP bound Ras to the active GTP-bound form.

TLS Online TPP Program

#Id: 9639

#Unit 4. Cell Communication and Cell Signaling

GRB2 has- 

Phosphotyrosine-binding SH2 domain

Two SH3 domains, bind to Sos