The deamination generates a G-T/C-T mismatch pair, MutL and MutS remove T from both G-T and C-T mismatches.

TLS Online TPP Program

#Id: 9044

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 9045

#Unit 4. Cell Communication and Cell Signaling

Switching mechanism of monomeric G proteins 

“Off” state, Removal of the γ phosphate by GTPase-catalyzed hydrolysis causes switch I and switch II to relax into a different conformation

TLS Online TPP Program

#Id: 9046

#Unit 4. Cell Communication and Cell Signaling

Monomeric G proteins, including Ras and various Ras-like proteins, do not directly bind to receptors but act as intermediate proteins in signal transduction pathways.

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#Id: 9047

#Unit 4. Cell Communication and Cell Signaling

Monomeric G proteins are evolutionarily ancient, as evidenced by their widespread functions examples include: 

eIF2

EF1α and EF2

Ran

Sar

Rab

Rho, Rac, and Cdc42

TLS Online TPP Program

#Id: 9048

#Unit 4. Cell Communication and Cell Signaling

All G protein–coupled receptors contain seven transmembrane α-helical regions (H1–H7). In many GPCRs a short α helix H8 lies parallel to the membrane surface, and a covalently bound palmitic acid group

TLS Online TPP Program

#Id: 9049

#Unit 4. Cell Communication and Cell Signaling

Three principal classes of G PCR that bind their ligand in different ways: