Endoplasmic reticulum sorting pathways

The biosynthetic, secretory pathway is responsible for protein sorting and delivery and allows, among other functions, for cell-cell communication through secreted products. This delivery process starts at the endoplasmic reticulum (ER), to finish in the cell plasma membrane or, in some cases, in specific intracellular organelles. To accomplish this, specific proteins must be properly directed to the correct destination, while other proteins are retained as residents within specific organelles along the way. 

Saraste, J. and Kuismanen, E. Pathways of protein sorting and membrane traffic between the rough endoplasmic reticulum and the Golgi complex. Semin. Cell Biol. 3 343-355,1992. 

Dtirr G, Strajde J, Plemper R, Elbs S, Klee SK, Catty P, Wolf DH, Rudolph HK (1998) The medial-Golgi ion pump Pmrl supplies the yeast secretory pathway with Ca2-f- and Mn2+ required for glycosylation, sorting, and endoplasmic reticulum-associated protein degradation. Mol Biol Cell 9 1149-1162... 

Poutska F, Irani NG, Feller A, Lu Y, Pourcel L, Frame K, Grotewold E. 2007. A trafficking pathway for anthocyanins overlaps with the endoplasmic reticulum-to-vacuole protein-sorting route in Arabidopsis and contributes to the formation of vacuolar inclusions. Plant Physiol 145 1323-1335. 

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