TY - JOUR
T1 - Golgi enzymes are enriched in perforated zones of Golgi cisternae but are depleted in COPI vesicles
AU - Kweon, Hee Seok
AU - Beznoussenko, Galina V.
AU - Micaroni, Massimo
AU - Polishchuk, Roman S.
AU - Trucco, Alvar
AU - Martella, Oliviano
AU - Di Giandomenico, Daniele
AU - Marra, Pierfrancesco
AU - Fusella, Aurora
AU - Di Pentima, Alessio
AU - Berger, Eric G.
AU - Geerts, Willie J C
AU - Koster, Abraham J.
AU - Burger, Koert N J
AU - Luini, Alberto
AU - Mironov, Alexander A.
PY - 2004/10
Y1 - 2004/10
N2 - In the most widely accepted version of the cisternal maturation/progression model of intra-Golgi transport, the polarity of the Golgi complex is maintained by retrograde transport of Golgi enzymes in COPI-coated vesicles. By analyzing enzyme localization in relation to the three-dimensional ultrastructure of the Golgi complex, we now observe that Golgi enzymes are depleted in COPI-coated buds and 50- to 60-nm COPI-dependent vesicles in a variety of different cell types. Instead, we find that Golgi enzymes are concentrated in the perforated zones of cisternal rims both in vivo and in a cell-free system. This lateral segregation of Golgi enzymes is detectable in some stacks during steady-state transport, but it was significantly prominent after blocking endoplasmic reticulum-to-Golgi transport. Delivery of transport carriers to the Golgi after the release of a transport block leads to a diminution in Golgi enzyme concentrations in perforated zones of cisternae. The exclusion of Golgi enzymes from COPI vesicles and their transport-dependent accumulation in perforated zones argues against the current vesicle-mediated version of the cisternal maturation/progression model.
AB - In the most widely accepted version of the cisternal maturation/progression model of intra-Golgi transport, the polarity of the Golgi complex is maintained by retrograde transport of Golgi enzymes in COPI-coated vesicles. By analyzing enzyme localization in relation to the three-dimensional ultrastructure of the Golgi complex, we now observe that Golgi enzymes are depleted in COPI-coated buds and 50- to 60-nm COPI-dependent vesicles in a variety of different cell types. Instead, we find that Golgi enzymes are concentrated in the perforated zones of cisternal rims both in vivo and in a cell-free system. This lateral segregation of Golgi enzymes is detectable in some stacks during steady-state transport, but it was significantly prominent after blocking endoplasmic reticulum-to-Golgi transport. Delivery of transport carriers to the Golgi after the release of a transport block leads to a diminution in Golgi enzyme concentrations in perforated zones of cisternae. The exclusion of Golgi enzymes from COPI vesicles and their transport-dependent accumulation in perforated zones argues against the current vesicle-mediated version of the cisternal maturation/progression model.
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U2 - 10.1091/mbc.E03-12-0881
DO - 10.1091/mbc.E03-12-0881
M3 - Article
C2 - 15282336
AN - SCOPUS:4644304941
VL - 15
SP - 4710
EP - 4724
JO - Molecular Biology of the Cell
JF - Molecular Biology of the Cell
SN - 1059-1524
IS - 10
ER -