The myelin proteolipid plasmolipin, forms oligomers and induces liquid ordered membranes in the Golgi apparatus
نویسندگان
چکیده
Myelin is comprised of a compactly stacked massive surface area of protein-poor, thick membrane that insulates axons to allow fast signal propagation. Increasing levels of the myelin protein plasmolipin (PLLP) were correlated with post-natal myelination. However its function is unknown. Here, the intracellular localization and dynamics of PLLP was characterized in primary glial and cultured cells using fluorescent protein (FP) tagged PLLP and anti-PLLP antibodies. PLLP localized to and recycled between the plasma membrane (PM) and the Golgi apparatus. In the Golgi apparatus PLLP forms oligomers based on fluorescence resonance energy transfer (FRET). PLLP oligomers blocked Golgi to PM transport of the secretory protein VSVG, but not a VSVG mutant with an elongated transmembrane domain. Laurdan staining analysis showed that this block is associated with PLLP-induced proliferation of liquid-ordered membranes. These findings show the capacity of PLLP to assemble potential myelin membrane precursor domains at the Golgi apparatus via its oligomerization and attraction of liquid ordered lipids. These data support a model whereby PLLP functions in myelin biogenesis by organization of myelin liquid ordered membranes in the Golgi apparatus. Jo ur na l o f C el l S ci en ce A cc ep te d m an us cr ip t
منابع مشابه
The myelin proteolipid plasmolipin forms oligomers and induces liquid-ordered membranes in the Golgi complex.
Myelin comprises a compactly stacked massive surface area of protein-poor thick membrane that insulates axons to allow fast signal propagation. Increasing levels of the myelin protein plasmolipin (PLLP) were correlated with post-natal myelination; however, its function is unknown. Here, the intracellular localization and dynamics of PLLP were characterized in primary glial and cultured cells us...
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