Assignment of Big MAP Kinase (PRKM7) to human chromosome 17 band p11.2 with somatic cell hybrids

Big MAP kinase BMK1 (Lee et al., 1995), also referred to as ERK5 (extracellular signal regulated kinase 5; Zhou et al., 1995) or PRKM7 (protein kinase mitogen activated 7; GDB Nomenclature) is a mitogen-activated protein (MAP) kinase. MAP kinase cascades represent one of the major systems used by eukaryotic cells to transduce extracellular stimuli into cellular responses including growth, differentiation and apoptosis. We have mapped PRKM7 to the deletion interval of the Smith-Magenis syndrome (SMS) on chromosome 17p11.2. SMS is a multiple congenital anomaly/mental retardation syndrome (Smith et al., 1986), associated with an interstitial deletion of chromosome 17p11.2. and is postulated to be a contiguous gene deletion syndrome, where haploinsufficiency of multiple, functionally unrelated genes are responsible for the phenotype (Greenberg et al., 1991, Juyal et al., 1996). PRKM7 is involved in the transcriptional activation of factors modulating expression of genes required for cell proliferation (Kato et al., 1997). Since alteration of a transcriptional regulator can have effects on multiple organ systems, possibly mediated by generalized dysregulation of gene expression, the contribution of haploin-sufficiency of PRKM7 to the SMS phenotype may be worth investigating.