Differential expression of Ran GTPase during HMBA-induced differentiation in murine erythroleukemia cells

Abstract

Murine erythroleukemia (MEL) cells undergo erythroid differentiation in vitro when treated with hexamethylene bisacetamide (HMBA).To identify genes involved in the commitment of MEL cells to differentiate, we screened a cDNA library constructed from HMBA-inducedcells by differential hybridization and isolated GTPaseRanas a down-regulated gene. We observed thatRanwas expressed in a biphasicmode. Following a decrease in mRNA level during the initial hours of induction,Ranre-expressed at 24–48 h, and gradually declinedagain. To investigate the role ofRanduring MEL differentiation we constructed MEL transfectants capable to express or blockRanmRNAproduction constitutively. No effects were observed on cell growth and proliferation. Blockage of Ran, however, interfered with MEL celldifferentiation resulting in a decrease of cell survival in the committed population.