Amn1 Background Information AMN1 (antagonist of mitotic exit network 1 homolog) is a 258 amino acid protein belonging to the AMN1 family. Encoded by a gene that maps to human chromosome 12p11.21, AMN1 contains twelve degenerate leucine-rich repeat (LRR) motifs and modulates Ste12 binding to promoters of multiple genes. As a daughter cell-specific protein, AMN1 inhibits ELL function to deactivate the mitotic exit state and reset the cell cycle in G1. AMN1 does not halt mitotic exit, but turns it off afterward. Induced by ELL after exit activation, AMN1 disrupts TEM1-Cdc15 interaction by competing with Cdc15 for TEM1 binding and by facilitating inactivation of Cdc14. Defects in AMN1 can result in disruption of both the spindle assembly and nuclear orientation checkpoints. AMN1 may also mediate gene activity and phenotypic diversity.
