Inherited a single mutant NF1 allele then develop neurofibromas, a benign tumor of the sheath cells that surround nerves, caused by loss of both alleles through LOH.

TLS Online TPP Program

#Id: 1343

#Unit 4. Cell Communication and Cell Signaling

RAS is a small monomeric G-proteins.

TLS Online TPP Program

#Id: 1344

#Unit 4. Cell Communication and Cell Signaling

RAS is connected to the membrane by a prenylated (lipid) tail.

TLS Online TPP Program

#Id: 1345

#Unit 4. Cell Communication and Cell Signaling

All Ras have the CAAX motifs at the C-terminus.

TLS Online TPP Program

#Id: 1346

#Unit 4. Cell Communication and Cell Signaling

Post-translational modifications of the CAAX motifs determine the subcellular localization and correct biological function of Ras proteins.

TLS Online TPP Program

#Id: 1347

#Unit 4. Cell Communication and Cell Signaling

SOS – Ras GEF

NF1 - Ras GAP

TLS Online TPP Program

#Id: 1348

#Unit 4. Cell Communication and Cell Signaling

RasD or RasONC  Replacement of the normal glycine 12 with any other amino acid (except proline) “locks” Ras in the active GTP-bound state.