  We have studied the pearling instability induced on hollow tubular lipid
vesicles by hydrophilic polymers with hydrophobic side groups along the
backbone. The results show that the polymer concentration is coupled to local
membrane curvature. The relaxation of a pearled tube is characterized by two
different well-separated time scales, indicating two physical mechanisms. We
present a model, which explains the observed phenomena and predicts polymer
segregation according to local membrane curvature at late stages.
