CK1BP is a 261 amino acid member of the dysbindin family and is a paralog of dysbindin, a protein trafficking protein involved in lysosome biosynthesis that has been associated with schizophrenia and muscular dystrophy. Human and rat HSMNP1 share 86% identity and both proteins contain three casein kinase II and PKC (protein kinase C) phosphorylation sites, a putative N-glycosylation site and a PEST motif at the C-terminus. HSMNP1 is a cytoplasmic protein and it specifically localizes to vesicles during the induction of apoptosis. In addition, HSMNP1 may be involved in normal as well as pathological myeloid development. Two isoforms of HSMNP1 exist due to alternative splicing events.