Abstract
Signal transduction via receptors for N-formylmethionyl peptide chemoattractants
(FPR) on human neutrophils is a highly regulated process. It involves
direct interaction of receptors with heterotrimeric G-proteins and
may be under the control of cytoskeletal elements. Evidence exists
suggesting that the cytoskeleton and/or the membrane skeleton determines
the distribution of FPR in the plane of the plasma membrane, thus
controlling FPR accessibility to different proteins in functionally
distinct membrane domains. In desensitized cells, FPR are restricted
to domains which are depleted of G proteins but enriched in cytoskeletal
proteins such as actin and fodrin. Thus, the G protein signal transduction
partners of FPR become inaccessible to the agonist-occupied receptor,
preventing cell activation. We are investigating the molecular basis
for the interaction of FPR with the membrane skeleton, and our results
suggest that FPR, and possibly other receptors, may directly bind
to cytoskeletal proteins such as actin.
Users
Please
log in to take part in the discussion (add own reviews or comments).