CYTOSKELETAL REGULATION OF MEMBRANE-TRANSPORT EVENTS

Recent advances in our understanding of the function of various components of the cytoskeleton indicate that, besides serving a structural role, the membrane skeleton may regulate the activity or number of transport proteins in the cell membrane. Abundant evidence indicates that individual proteins of the cytoskeletal system bind directly to transport proteins, resulting in the three-dimensional organization of a structure termed the membrane skeleton. This interaction between cytoskeleton and transporters can most readily be interpreted to serve a structural role, keeping the transporters in specific domains. However, because disruption or alteration of the cytoskeletal organization can lead to changes in transport, the interaction may play a key role in regulating transporter activity. Elements of the cytoskeleton also interact with components of second messenger systems. Thus, the cytoskeleton could play a regulatory role by altering the availability of signal transducers or by being an integral part of the signal transduction system.