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Hop diffusion - is a non-Brownian diffusion of proteins and lipid molecules within the plasma membrane. Hop diffusion occurs due to the discontinuity of the cell cytoplasmic membrane. According to the Fences and pickets model, plasma membrane is compartmentalized by actin-based membrane-skeleton “fences”, that occur when cytoplasmic domains collide with the actin-based membrane skeleton; and anchored-transmembrane protein “pickets”. Due to these obstacles membrane proteins undergo temporary confinement within 30–700- nm compartments with infrequent intercompartmental hops. Hops between adjacent compartments presumably occur due to: * thermal fluctuations of the membrane and following creation of spaces between cytoplasmic membrane layer and cytoskeleton, large enough to allow the passage of integral membrane proteins; * temporal actin filament brackage; * membrane molecules have sufficient kinetic energy to cross the barrier While simple Brownian diffusion is isotropic and homogeneous, hop diffusion is more complex and combines free diffusion, which occurs inside cell membrane compartments, and infrequent intercompartmental transitions (hops). ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「hop diffusion」の詳細全文を読む スポンサード リンク
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