The Role of the Actin Cytoskeleton and Lipid Rafts in the Localization and Function of the ABCC1 Transporter
Figure 2
Models of ABC transporter localization in membrane domains and its interactions with the cortical actin cytoskeleton. The plasma membrane is viewed from the inside of the cell showing the inner face of the membrane. Three models are depicted. (a) The lipid raft model of ABC transporter retention in a domain. The ABC transporter is restricted in lateral movement by virtue of being in a lipid raft. The lipid raft is stabilized by the cortical actin cytoskeleton through the hypothetical protein RAL, which is linked to actin. The ABC transporter in turn may interact with RAL. (b) The anchored protein picket model of ABC transporter retention in a domain (adapted from [32]). The ABC transporter is restricted in lateral movement by virtue of colliding with picket proteins that are linked to cortical actin and fence the corral in which the ABC transporter is temporarily contained. (c) The fence model of ABC transporter retention in a domain (adapted from [32]). The ABC transporter is restricted in lateral movement by virtue of the collision of its cytoplasmic domain with cortical actin just underneath the plasma membrane, which forms a fence surrounding the corral in which the ABC transporter is temporarily contained. No distinction is made between human ABC and rodent Abc transporters for reasons of simplicity. RAL: raft actin linker protein; APP: anchored protein picket.
