The Male Specific Lethal (MSL) complex provides an exquisite example of an epigenetic modulator that is involved in chromosome-wide as well as individual gene regulation in flies and mammals. In this review, we discuss the recent advances in biochemical and structural understanding of the MSL complex modules and how they function in X chromosome regulation in flies. Moreover, we describe possible conserved and dosage compensation-independent functions of the MSL complex with a particular focus on mammalian systems.
