Prothymosin alpha interacts with the CREB-binding protein and potentiates transcription.
Prothymosin alpha (ProTalpha) is a histone H1-binding protein localized in sites of active transcription in the nucleus. We report here that ProTalpha physically interacts with the CREB-binding protein (CBP), which is a versatile transcription co-activator. Confocal laser scanning microscopy reveals that ProTalpha partially colocalizes with CBP in discrete subnuclear domains. Using transient transfections, we show that ProTalpha synergizes with CBP and stimulates AP1- and NF-kappaB-dependent transcription. Furthermore, overexpression of ProTalpha enhances the transactivation potential of CBP. These findings reveal a new function for ProTalpha in transcription activation, probably through CBP-mediated recruitment to different promoters.
Karetsou
Zoe
Z
Laboratory of Biological Chemistry, University of Ioannina Medical School, 45110 Ioannina, Greece.
Kretsovali
Adroniki
A
Murphy
Carol
C
Tsolas
Orestes
O
Papamarcaki
Thomais
T
D000818:Animals; D050882:CREB-Binding Protein; D002417:Cattle; D005982:Glutathione Transferase / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D016328:NF-kappa B / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D011233:Precipitin Tests; D011498:Protein Precursors / Q000378:metabolism*; D051381:Rats; D013947:Thymosin / Q000031:analogs & derivatives* / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology*
D016328:NF-kappa B; D009687:Nuclear Proteins; D011498:Protein Precursors; D015534:Trans-Activators; D018808:Transcription Factor AP-1; C040782:prothymosin alpha; D013947:Thymosin; D050882:CREB-Binding Protein; C494363:CREBBP protein, human; C494365:Crebbp protein, rat; D005982:Glutathione Transferase