Medicine and Health Sciences Commons^™

Regulation Of Stress-Inducible Phosphoprotein 1 Nuclear Retention By Protein Inhibitor Of Activated Stat Pias1, Iaci N. Soares, Fabiana A. Caetano, Jordan Pinder, Bruna Roz Rodrigues, Flavio H. Beraldo, Valeriy G. Ostapchenko, Chantal Durette, Grace Schenatto Pereira, Marilene H. Lopes, Nicolle Queiroz-Hazarbassanov, Isabela W. Cunha, Paulo I. Sanematsu, Sergio Suzuki, Luiz F. Bleggi-Torres, Caroline Schild-Poulter, Pierre Thibault, Graham Dellaire, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado

Anatomy and Cell Biology Publications

Stress-inducible phosphoprotein 1 (STI1), a cochaperone for Hsp90, has been shown to regulate multiple pathways in astrocytes, but its contributions to cellular stress responses are not fully understood. We show that in response to irradiation-mediated DNA damage stress STI1 accumulates in the nucleus of astrocytes. Also, STI1 haploinsufficiency decreases astrocyte survival after irradiation. Using yeast two-hybrid screenings we identified several nuclear proteins as STI1 interactors. Overexpression of one of these interactors, PIAS1, seems to be specifically involved in STI1 nuclear retention and in directing STI1 and Hsp90 to specific sub-nuclear regions. PIAS1 and STI1 co-immunoprecipitate and PIAS1 can function as …