Prothymosin alpha, a mammalian c-myc-regulated acidic nuclear protein, provokes the decondensation of human chromosomes in vitro

Prothymosin (ProT alpha) is an acidic nuclear protein., widely distributed in mammalian cells, whose expression is regulated by c-myc and linked to ce ll proliferation. ProT alpha interacts with histone Hl via its acidic domai n, and its overexpression provokes the unfolding of chromatin fibers. Here we show that incubation of human native metaphase chromosomes with ProT alp ha induces their extensive unravelling suggesting a function of this protei n in chromosome decondensation. Copyright (C) 2001 S. Karger AG, Basel.