The activity of transcription factors is tightly modulated by posttranslational modifications affecting stability, localization, and protein-protein interactions. Conjugation to SUMO is a reversible posttranslational modification that has been shown to regulate important transcription factors involved in cell proliferation, differentiation, and tumor suppression. Here, we demonstrate that the erythroid transcription factor GATA-1 is sumoylated in vitro and in vivo and map the single lysine residue involved in SUMO-1 attachment. We show that the nuclear RING finger protein PIASy promotes sumoylation of GATA-1 and dramatically represses its transcriptional activity. We present evidence that a nonsumoylatable GATA-1 mutant is indistinguishable from the WT protein in its ability to transactivate a reporter gene in mammalian cells and in its ability to trigger endogenous globin expression in Xenopus explants. These observations open interesting questions about the biological role of this posttranslational modification of GATA-1.

Modification of the erythroid transcription factor GATA-1 by SUMO-1

COLLAVIN, LICIO;DEL SAL, GIANNINO
2004

Abstract

The activity of transcription factors is tightly modulated by posttranslational modifications affecting stability, localization, and protein-protein interactions. Conjugation to SUMO is a reversible posttranslational modification that has been shown to regulate important transcription factors involved in cell proliferation, differentiation, and tumor suppression. Here, we demonstrate that the erythroid transcription factor GATA-1 is sumoylated in vitro and in vivo and map the single lysine residue involved in SUMO-1 attachment. We show that the nuclear RING finger protein PIASy promotes sumoylation of GATA-1 and dramatically represses its transcriptional activity. We present evidence that a nonsumoylatable GATA-1 mutant is indistinguishable from the WT protein in its ability to transactivate a reporter gene in mammalian cells and in its ability to trigger endogenous globin expression in Xenopus explants. These observations open interesting questions about the biological role of this posttranslational modification of GATA-1.
File in 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: http://hdl.handle.net/11368/1693254
 Attenzione

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

Citazioni
  • ???jsp.display-item.citation.pmc??? 30
  • Scopus 58
  • ???jsp.display-item.citation.isi??? 59
social impact