secretory pathway

 There are two main classes of traffic intermediates that operate in intracellular trafficking pathways: small round vesicles, and large pleiomorphic carriers (LPCs).

 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.

LPCs appear to form by en bloc extrusion and cleavage of large membrane areas of the donor organelle.

See also

 secretory proteins

Video

 The secretory pathway

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References

 Lowe M, Barr FA. Inheritance and biogenesis of organelles in the secretory pathway. Nat Rev Mol Cell Biol. 2007 May 16; PMID: 17505521

 Luini A, Ragnini-Wilson A, Polishchuck RS, De Matteis MA. Large pleiomorphic traffic intermediates in the secretory pathway. Curr Opin Cell Biol. 2005 Aug;17(4):353-61. PMID: 15993575

 Robinson MS. Adaptable adaptors for coated vesicles. Trends Cell Biol. 2004 Apr;14(4):167-74. PMID: 15066634

 Seidah NG, Prat A. Precursor convertases in the secretory pathway, cytosol and extracellular milieu. Essays Biochem. 2002;38:79-94. PMID: 12463163

 Kuznetsov G, Nigam SK. Folding of secretory and membrane proteins. N Engl J Med 1998;339:1688-1695.