Mob1 is an essential Saccharomyces cerevisiae protein, identified from a two-hybrid screen, that binds Mps1p, a protein kinase essential for spindle pole body duplication and mitotic checkpoint regulation. Mob1 contains no known structural motifs; however MOB1 is a member of a conserved gene family and shares sequence similarity with a nonessential yeast gene, MOB2. Mob1 is a phosphoprotein in vivo and a substrate for the Mps1p kinase in vitro. Conditional alleles of MOB1 cause a late nuclear division arrest at restrictive temperature [1]. This family also includes phocein Swiss:Q9QYW3, a rat protein that by yeast two hybrid interacts with striatin [2].

1: MOB1, an essential yeast gene required for completion of mitosis and maintenance of ploidy. Luca FC, Winey M; Mol Biol Cell 1998;9:29-46. PMID:9436989

2: Molecular cloning and characterization of phocein, a protein found from the Golgi complex to dendritic spines. Baillat G, Moqrich A, Castets F, Baude A, Bailly Y, Benmerah A, Monneron A; Mol Biol Cell 2001;12:663-673. PMID:11251078