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Peri-Golgi vesicles contain retrograde but not anterograde proteins consistent with the cisternal progression model of intra-Golgi transport.

Martinez-Menárguez JA, Prekeris R, Oorschot VM, Scheller R, Slot JW, Geuze HJ, Klumperman J - J. Cell Biol. (2001)

Bottom Line: A cisternal progression mode of intra-Golgi transport requires that Golgi resident proteins recycle by peri-Golgi vesicles, whereas the alternative model of vesicular transport predicts anterograde cargo proteins to be present in such vesicles.We found significant levels of the Golgi resident enzyme mannosidase II and the transport machinery proteins giantin, KDEL-receptor, and rBet1 in coatomer protein I-coated cisternal rims and peri-Golgi vesicles.By contrast, when cells expressed vesicular stomatitis virus protein G this anterograde marker was largely absent from the peri-Golgi vesicles.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, School of Medicine, University of Murcia, 30071 Murcia, Spain.

ABSTRACT
A cisternal progression mode of intra-Golgi transport requires that Golgi resident proteins recycle by peri-Golgi vesicles, whereas the alternative model of vesicular transport predicts anterograde cargo proteins to be present in such vesicles. We have used quantitative immuno-EM on NRK cells to distinguish peri-Golgi vesicles from other vesicles in the Golgi region. We found significant levels of the Golgi resident enzyme mannosidase II and the transport machinery proteins giantin, KDEL-receptor, and rBet1 in coatomer protein I-coated cisternal rims and peri-Golgi vesicles. By contrast, when cells expressed vesicular stomatitis virus protein G this anterograde marker was largely absent from the peri-Golgi vesicles. These data suggest a role of peri-Golgi vesicles in recycling of Golgi residents, rather than an important role in anterograde transport.

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Man II (15 nm gold)–positive peri-Golgi (G) vesicles (arrows) lack COPII (10 nm gold), which is restricted to vesicles close to the ER. Bar, 200 nm.
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fig2: Man II (15 nm gold)–positive peri-Golgi (G) vesicles (arrows) lack COPII (10 nm gold), which is restricted to vesicles close to the ER. Bar, 200 nm.

Mentions: Lateral of the Golgi cisternae, clusters of 50–60 nm diameter vesicles were found, 41% of which beared a visible cytoplasmic COP coat (an example of a COP coat is found in Fig. 1 C). COP coats are clearly distinguishable in cryosections and differ from clathrin coats by a thinner and more regular appearance (for an example of a clathrin coat see Fig. 4 C). A distinction between COPII and COPI coats can only be made by molecular criteria. In agreement with studies in other cells (Hay et al., 1998; Martínez-Menárguez et al., 1999), we found that COPII labeling was confined to restricted areas, often on ER buds or on vesicles in close vicinity to an ER cisterna (Fig. 2), whereas COPI label was more widely dispersed and also present on the peri-Golgi vesicles and COP-coated rims at the Golgi cisternae (Fig. 3). Notably, significant label of Man II was present in peri-Golgi vesicles (Figs. 1–3, arrows) where it colocalized with COPI (Fig. 3) but not COPII (Fig. 2). Quantitative analysis of double labelings for Man II and either COPI or COPII showed that ∼20% of the Man II–positive peri-Golgi vesicles (vesicles within a distance of 200 nm lateral from the stack) was labeled for COPI, and only 2% was labeled for COPII (out of 100 Man II–positive vesicles for each). These data defined the COP-coated cisternal buds and almost all coated peri-Golgi vesicles as the COPI type.


Peri-Golgi vesicles contain retrograde but not anterograde proteins consistent with the cisternal progression model of intra-Golgi transport.

Martinez-Menárguez JA, Prekeris R, Oorschot VM, Scheller R, Slot JW, Geuze HJ, Klumperman J - J. Cell Biol. (2001)

Man II (15 nm gold)–positive peri-Golgi (G) vesicles (arrows) lack COPII (10 nm gold), which is restricted to vesicles close to the ER. Bar, 200 nm.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2199342&req=5

fig2: Man II (15 nm gold)–positive peri-Golgi (G) vesicles (arrows) lack COPII (10 nm gold), which is restricted to vesicles close to the ER. Bar, 200 nm.
Mentions: Lateral of the Golgi cisternae, clusters of 50–60 nm diameter vesicles were found, 41% of which beared a visible cytoplasmic COP coat (an example of a COP coat is found in Fig. 1 C). COP coats are clearly distinguishable in cryosections and differ from clathrin coats by a thinner and more regular appearance (for an example of a clathrin coat see Fig. 4 C). A distinction between COPII and COPI coats can only be made by molecular criteria. In agreement with studies in other cells (Hay et al., 1998; Martínez-Menárguez et al., 1999), we found that COPII labeling was confined to restricted areas, often on ER buds or on vesicles in close vicinity to an ER cisterna (Fig. 2), whereas COPI label was more widely dispersed and also present on the peri-Golgi vesicles and COP-coated rims at the Golgi cisternae (Fig. 3). Notably, significant label of Man II was present in peri-Golgi vesicles (Figs. 1–3, arrows) where it colocalized with COPI (Fig. 3) but not COPII (Fig. 2). Quantitative analysis of double labelings for Man II and either COPI or COPII showed that ∼20% of the Man II–positive peri-Golgi vesicles (vesicles within a distance of 200 nm lateral from the stack) was labeled for COPI, and only 2% was labeled for COPII (out of 100 Man II–positive vesicles for each). These data defined the COP-coated cisternal buds and almost all coated peri-Golgi vesicles as the COPI type.

Bottom Line: A cisternal progression mode of intra-Golgi transport requires that Golgi resident proteins recycle by peri-Golgi vesicles, whereas the alternative model of vesicular transport predicts anterograde cargo proteins to be present in such vesicles.We found significant levels of the Golgi resident enzyme mannosidase II and the transport machinery proteins giantin, KDEL-receptor, and rBet1 in coatomer protein I-coated cisternal rims and peri-Golgi vesicles.By contrast, when cells expressed vesicular stomatitis virus protein G this anterograde marker was largely absent from the peri-Golgi vesicles.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology, School of Medicine, University of Murcia, 30071 Murcia, Spain.

ABSTRACT
A cisternal progression mode of intra-Golgi transport requires that Golgi resident proteins recycle by peri-Golgi vesicles, whereas the alternative model of vesicular transport predicts anterograde cargo proteins to be present in such vesicles. We have used quantitative immuno-EM on NRK cells to distinguish peri-Golgi vesicles from other vesicles in the Golgi region. We found significant levels of the Golgi resident enzyme mannosidase II and the transport machinery proteins giantin, KDEL-receptor, and rBet1 in coatomer protein I-coated cisternal rims and peri-Golgi vesicles. By contrast, when cells expressed vesicular stomatitis virus protein G this anterograde marker was largely absent from the peri-Golgi vesicles. These data suggest a role of peri-Golgi vesicles in recycling of Golgi residents, rather than an important role in anterograde transport.

Show MeSH
Related in: MedlinePlus