Assignment of the <i>PHACTR1</i> gene to bovine chromosome 23q24 by fluorescence in situ hybridization and radiation hybrid mapping

The phosphatase and actin regulator (PHACTR) proteins represent a family of protein phosphatase 1 (PP1) and actin regulatory proteins. PP1 is a multifunctional enzyme with diverse roles in the nervous system, including regulation of synaptic activity and dendritic morphology. In rat the Phactr1 gene was cloned for the first time as the prototypical member of this family (Allen et al., 2004). By searching databases for sequences similar to rat Phactr1, Allen et al. (2004) identified a family of four PHACTR genes in mouse and human. It was shown that human PHACTR1, which was designated KIAA1733, has been detected previously by sequencing hippocampus cDNA clones (Nagase et al., 2000). Functional studies determined that recombinant rat Phactr1 inhibited PP1 enzymatic activity in a concentration-dependent manner and detected highest expression in brain and lower levels in lung, heart, kidney, and testis (Allen et al., 2004). The human PHACTR1 gene consists of 14 exons spanning about 570 kb on chromosome 6p23 (NCBI map viewer, human genome build 34) and the homologous rat Phactr1 gene consists of 23 exons and is located on chromosome 17p12 (NCBI map viewer, rat genome build 2). The PHACTR1 gene has not been identified in cattle, however a bovine fetal kidney EST sequence (Accession AV607621) corresponding to the 3) end of the human homolog cDNA sequence can be found (NCBI map viewer, human genome build 34). We report here the assignment of the bovine PHACTR1 gene to BTA23q24 by fluorescence in situ hybridization (FISH) and radiation hybrid (RH) mapping.