To establish the specific contribution to protein topology of KKXX and KDEL retrieval motifs, we have determined by immunogold electron microscopy and cell fractionation the intracellular distribution at steady state of the transmembrane and anchorless versions of human CD8 protein, tagged with KKXX (CD8-E19) and KDEL (CD8-K), respectively, and stably expressed in epithelial rat cells (Martire, G,, Mottola, G., Pascale, M. C., Malagolini, N., Turrini, I., Serafini-Cessi, F,, Jackson, M, R., and Bonatti, S, (1996) J. Biol. Chem. 271, 3541-3547). The CD8-E19 protein is represented by a single form, initially O-glycosylated: only about half of it is located in the endoplasmic reticulum, whereas more than 30% of the total is present in the intermediate compartment and cis-Golgi complex. In the latter compartments, CD8-E19 colocalizes with beta-coat protein (COP) (COPI component) and shows the higher density of labeling. Conversely, about 90% of the total CD8-KDEL protein is localized in clusters on the endoplasmic reticulum, where significant co-localization with Sec-23p (COPII component) is observed, and unglycosylated and initially O-glycosylated forms apparently constitute a single pool. Altogether, these results suggest that KKXX and KDEL retrieval motifs have different topological effects on theirs own at steady state: the first results in a specific enrichment in the intermediate compartment and cis-Golgi complex, and the latter dictates residency in the endoplasmic reticulum.

A DIFFERENT INTRACELLULAR DISTRIBUTION OF A SINGLE REPORTER PROTEIN IS DETERMINED AT STEADY STATE BY KKXX RETRIEVAL SIGNALS / Lotti, Lavinia Vittoria; Mottola, G.; Torrisi, Maria Rosaria; Bonatti, S.. - In: THE JOURNAL OF BIOLOGICAL CHEMISTRY. - ISSN 0021-9258. - STAMPA. - 274:(1999), pp. 10413-10420. [10.1074/jbc.274.15.10413]

A DIFFERENT INTRACELLULAR DISTRIBUTION OF A SINGLE REPORTER PROTEIN IS DETERMINED AT STEADY STATE BY KKXX RETRIEVAL SIGNALS.

LOTTI, Lavinia Vittoria;TORRISI, Maria Rosaria;
1999

Abstract

To establish the specific contribution to protein topology of KKXX and KDEL retrieval motifs, we have determined by immunogold electron microscopy and cell fractionation the intracellular distribution at steady state of the transmembrane and anchorless versions of human CD8 protein, tagged with KKXX (CD8-E19) and KDEL (CD8-K), respectively, and stably expressed in epithelial rat cells (Martire, G,, Mottola, G., Pascale, M. C., Malagolini, N., Turrini, I., Serafini-Cessi, F,, Jackson, M, R., and Bonatti, S, (1996) J. Biol. Chem. 271, 3541-3547). The CD8-E19 protein is represented by a single form, initially O-glycosylated: only about half of it is located in the endoplasmic reticulum, whereas more than 30% of the total is present in the intermediate compartment and cis-Golgi complex. In the latter compartments, CD8-E19 colocalizes with beta-coat protein (COP) (COPI component) and shows the higher density of labeling. Conversely, about 90% of the total CD8-KDEL protein is localized in clusters on the endoplasmic reticulum, where significant co-localization with Sec-23p (COPII component) is observed, and unglycosylated and initially O-glycosylated forms apparently constitute a single pool. Altogether, these results suggest that KKXX and KDEL retrieval motifs have different topological effects on theirs own at steady state: the first results in a specific enrichment in the intermediate compartment and cis-Golgi complex, and the latter dictates residency in the endoplasmic reticulum.
1999
01 Pubblicazione su rivista::01a Articolo in rivista
A DIFFERENT INTRACELLULAR DISTRIBUTION OF A SINGLE REPORTER PROTEIN IS DETERMINED AT STEADY STATE BY KKXX RETRIEVAL SIGNALS / Lotti, Lavinia Vittoria; Mottola, G.; Torrisi, Maria Rosaria; Bonatti, S.. - In: THE JOURNAL OF BIOLOGICAL CHEMISTRY. - ISSN 0021-9258. - STAMPA. - 274:(1999), pp. 10413-10420. [10.1074/jbc.274.15.10413]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/256512
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 7
  • Scopus 18
  • ???jsp.display-item.citation.isi??? 19
social impact