The combined hydrophobic and hydrophilic tendencies of individual amino acid residues in proteins can be expressed as hydropathies. The greater a side chain’s hydropathy, the more likely it is to occupy the interior of a protein.

TLS Online TPP Program

#Id: 9322

#XL - T Zoology

Guanylate cyclase–activating proteins, 

bind to guanylate cyclase and stimulate its activity, elevating cGMP level and causing the cGMP-gated ion channels to reopen.

TLS Online TPP Program

#Id: 9323

#XL - T Zoology

Terminate the visual response involves phosphorylation of activated (R*) rhodopsin, but not its dark (R) form

TLS Online TPP Program

#Id: 9324

#XL - T Zoology

Rhodopsin kinase, a member of the GRK family of kinases catalyzes phosphorylation of activated rhodopsin

TLS Online TPP Program

#Id: 9325

#XL - T Zoology

Each opsin molecule has multiple principal serine and threonine phosphorylation sites on its cytosol-facing C-terminal segment.

TLS Online TPP Program

#Id: 9326

#XL - T Zoology

TLS Online TPP Program

#Id: 9328

#XL - T Zoology

Arrestin binds tightly to rhodopsin only when rhodopsin kinase has phosphorylated a sufficient number of C-terminal serines and threonines.