GATA-1 isoforms differently contribute to the production and compartmentation of reactive oxygen species in the myeloid leukemia cell line K562.

Maintenance of a balanced expression of the two isoforms of the transcription factor GATA-1, the full-length protein (GATA-1 ) and a shorter isoform (GATA-1 ), contributes to control hematopoiesis, whereas their dysregulation can alter the differentiation/proliferation potential of hematopoietic precursors thereby eventually leading to a variety of hematopoietic disorders. Although it is well established that these isoforms play opposite roles in these remarkable processes, most of the molecular pathways involved remain unknown. Here, we demonstrate that GATA-1 and GATA-1 are able to differently influence intracellular redox states and reactive oxygen species (ROS) compartmentation in the erythroleukemic K562 cell line, thus shedding novel mechanistic insights into the processes of cell proliferation and apoptosis resistance in myeloid precursors. Furthermore, given the role played by ROS signaling as a strategy to escape apoptosis and evade cell-mediated immunity in myeloid cells, this study highlights a mechanism through which aberrant expression of GATA-1 isoforms could play a role in the leukemogenic process.