TY - JOUR
T1 - Small cargo proteins and large aggregates can traverse the Golgi by a common mechanism without leaving the lumen of cisternae
AU - Mironov, Alexander A.
AU - Beznoussenko, Galina V.
AU - Nicoziani, Paolo
AU - Martella, Oliviano
AU - Trucco, Alvar
AU - Kweon, Hee Seok
AU - Giandomenico, Daniele Di
AU - Polishchuk, Roman S.
AU - Fusella, Aurora
AU - Lupetti, Pietro
AU - Berger, Eric G.
AU - Geerts, Willie J C
AU - Koster, Abraham J.
AU - Burger, Koert N J
AU - Luini, Alberto
PY - 2001/12/24
Y1 - 2001/12/24
N2 - Procollagen (PC)-I aggregates transit through the Golgi complex without leaving the lumen of Golgi cisternae. Based on this evidence, we have proposed that PC-I is transported across the Golgi stacks by the cisternal maturation process. However, most secretory cargoes are small, freely diffusing proteins, thus raising the issue whether they move by a transport mechanism different than that used by PC-I. To address this question we have developed procedures to compare the transport of a small protein, the G protein of the vesicular stomatitis virus (VSVG), with that of the much larger PC-I aggregates in the same cell. Transport was followed using a combination of video and EM, providing high resolution in time and space. Our results reveal that PC-I aggregates and VSVG move synchronously through the Golgi at indistinguishable rapid rates. Additionally, not only PC-I aggregates (as confirmed by ultrarapid cryofixation), but also VSVG, can traverse the stack without leaving the cisternal lumen and without entering Golgi vesicles in functionally relevant amounts. Our findings indicate that a common mechanism independent of anterograde dissociative carriers is responsible for the traffic of small and large secretory cargo across the Golgi stack.
AB - Procollagen (PC)-I aggregates transit through the Golgi complex without leaving the lumen of Golgi cisternae. Based on this evidence, we have proposed that PC-I is transported across the Golgi stacks by the cisternal maturation process. However, most secretory cargoes are small, freely diffusing proteins, thus raising the issue whether they move by a transport mechanism different than that used by PC-I. To address this question we have developed procedures to compare the transport of a small protein, the G protein of the vesicular stomatitis virus (VSVG), with that of the much larger PC-I aggregates in the same cell. Transport was followed using a combination of video and EM, providing high resolution in time and space. Our results reveal that PC-I aggregates and VSVG move synchronously through the Golgi at indistinguishable rapid rates. Additionally, not only PC-I aggregates (as confirmed by ultrarapid cryofixation), but also VSVG, can traverse the stack without leaving the cisternal lumen and without entering Golgi vesicles in functionally relevant amounts. Our findings indicate that a common mechanism independent of anterograde dissociative carriers is responsible for the traffic of small and large secretory cargo across the Golgi stack.
KW - Golgi complex
KW - Intracellular traffic
KW - Procollagen
KW - Transport vesicles
KW - VSVG
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U2 - 10.1083/jcb.200108073
DO - 10.1083/jcb.200108073
M3 - Article
C2 - 11756473
AN - SCOPUS:0035945357
VL - 155
SP - 1225
EP - 1238
JO - Journal of Cell Biology
JF - Journal of Cell Biology
SN - 0021-9525
IS - 7
ER -