The classical concept of the static lipid-protein architecture of the biological membrane has been completely remodeled by the new concept of the fluid mosaic model proposed by Singer and Nicolson (1972). This new theory has provided many useful clues toward better understanding of the membrane functions. Membrane lipids are now recognized as precursors of bioactive molecules which are generated upon cell stimulation by agonists and act as second messengers produced by various phospholipases. It is thus well accepted that membrane lipids play crucial roles in signal transduction.