Large pleiomorphic traffic intermediates in the secretory pathway.
There are two main classes of traffic intermediates that operate in intracellular trafficking pathways: small round vesicles, and large pleiomorphic carriers (LPCs). While both are essential, the LPCs appear to be responsible for moving the bulk of the secretory traffic between distant compartments. LPCs are much larger and more variable in shape than vesicles, and they have evident interconnected tubular and saccular/cisternal components. They appear to form by en bloc extrusion and cleavage of large membrane areas of the donor organelle. Although many proteins and lipids that are involved in LPC formation have been identified, the intrinsic complexity of these carriers and current technical limitations mean that a coherent picture of the process of of LPC formation is only just beginning to emerge.
Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, 66030 Santa Maria Imbaro, Chieti, Italy. luini@negrisud.it
Alberto
A
Luini
Antonella
A
Ragnini-Wilson
Roman S
RS
Polishchuck
Maria Antonietta
MA
De Matteis
D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D006056:Golgi Apparatus / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism*; D020409:Molecular Motor Proteins / Q000378:metabolism
D002352:Carrier Proteins; D020409:Molecular Motor Proteins