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 (PMID:9436989). This family also includes phocein Q9QYW3 a rat protein that by yeast two hybrid interacts with striatin (PMID:11251078).
The MOB kinase activator family includes MOB1, 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. Conditional alleles of MOB1 cause a late nuclear division arrest at restrictive temperature [ (PUBMED:9436989) ]. This family also includes the MOB-like protein phocein, an intracellular protein that interacts with striatin and may play a role in membrane trafficking [ (PUBMED:11872741) ].
Family alignment:
There are 5928 Mob1_phocein domains in 5923 proteins in SMART's nrdb database.
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Evolution (species in which this domain is found)
Taxonomic distribution of proteins containing Mob1_phocein domain.
This tree includes only several representative species. The complete taxonomic breakdown of all proteins with Mob1_phocein domain is also avaliable.
Click on the protein counts, or double click on taxonomic names to display all proteins containing Mob1_phocein domain in the selected taxonomic class.
Molecular cloning and characterization of phocein, a protein found from the Golgicomplex to dendritic spines.
Mol Biol Cell. 2001; 12: 663-73
Display abstract
Phocein is a widely expressed, highly conserved intracellular protein of 225amino acids, the sequence of which has limited homology to the sigma subunitsfrom clathrin adaptor complexes and contains an additional stretch bearing aputative SH3-binding domain. This sequence is evolutionarily very conserved (80% identity between Drosophila melanogaster and human). Phocein was discovered by a yeast two-hybrid screen using striatin as a bait. Striatin, SG2NA, and zinedin,the three mammalian members of the striatin family, are multimodular, WD-repeat, and calmodulin-binding proteins. The interaction of phocein with striatin, SG2NA,and zinedin was validated in vitro by coimmunoprecipitation and pull-downexperiments. Fractionation of brain and HeLa cells showed that phocein isassociated with membranes, as well as present in the cytosol where it behaves as a protein complex. The molecular interaction between SG2NA and phocein wasconfirmed by their in vivo colocalization, as observed in HeLa cells whereantibodies directed against either phocein or SG2NA immunostained the Golgicomplex. A 2-min brefeldin A treatment of HeLa cells induced the redistributionof both proteins. Immunocytochemical studies of adult rat brain sections showedthat phocein reactivity, present in many types of neurons, is strictlysomato-dendritic and extends down to spines, just as do striatin and SG2NA.
