MSL1_dimer is the short coiled dimerisation domain of higher eukaryotic MSL1, part of the MSL or Male-Specific Lethal complex. This complex regulates the dosage compensation of the male X chromosome in Drosophila and other eukaryotes. The structure of the MSL1/MSL2 core shows that two MSL2 subunits bind to a dimer formed by two molecules of MSL1. MSL11 is a substrate for MSL2 E3 ubiquitin ligase activity [1].

1: Msl1-mediated dimerization of the dosage compensation complex is essential for male X-chromosome regulation in Drosophila. Hallacli E, Lipp M, Georgiev P, Spielman C, Cusack S, Akhtar A, Kadlec J; Mol Cell. 2012;48:587-600. PMID:23084835