In the dark, most transducin is localized to the outer segment, while most arrestin is found in other parts of the cell; in this condition, vision is most sensitive to very low light levels.

TLS Online TPP Program

#Id: 9627

#XL - T Zoology

Monoubiquitinylation of the HER1 cytosolic domain by the E3 ubiquitin ligase c-Cbl

TLS Online TPP Program

#Id: 9628

#XL - T Zoology

c-Cbl 

adds a single ubiquitin to a given lysine of a protein

TLS Online TPP Program

#Id: 9629

#XL - T Zoology

c-Cbl contains: 

a domain that binds directly to phosphorylated EGF receptors

a RING finger domain, which recruits ubiquitin-conjugating enzymes and mediates transfer of ubiquitin to the receptor

TLS Online TPP Program

#Id: 9630

#XL - T Zoology

Other EGF family receptors HER2, HER3, and HER4 do not undergo internalization after exposure to ligand

TLS Online TPP Program

#Id: 9631

#XL - T Zoology

Monomeric Ras protein 

(∼170 amino acids) belongs to the GTPase superfamily of

intracellular switch proteins

TLS Online TPP Program

#Id: 9632

#XL - T Zoology

Ras has an intrinsically slower rate of GTP hydrolysis, so Ras∙GTP requires the assistance of another protein, GAP.