 As FSL constructs are anchored in the membrane via a lipid tail (L) it is believed they do not participate in signal transduction, but may be designed to act as agonists or antagonists of the initial binding event.FSL constructs will not actively pass through the plasma membrane but may enter the cell via membrane invagination and endocytosis.The "koding" of cells is stable (subject to the rate of turnover of the membrane components).