Interaction of Sedlin with PAM14.

Sedlin is an evolutionarily conserved and ubiquitously expressed protein that is encoded by the gene SEDL. Mutations in the latter are known to be causative for spondyloepiphyseal dysplasia tarda. However, the mechanism underlying this remains unclear. We have previously shown that Sedlin interacts with the intracellular chloride channel proteins CLIC1 and CLIC2 in the cytoplasm. In this report we show that Sedlin is also physically associated with protein associated with MRG 14 kDa (PAM14), a nuclear protein that interacts with the transcription factor MORF4-related gene on chromosome 15 (MRG15). This was suggested by yeast two-hybrid screening and was confirmed with GST pull-down and immunoprecipitation assays. Moreover, we demonstrate that the C-terminus of Sedlin and the N-terminus of PAM14 are critical for their interaction. Together, these results suggest that nucleus-localized Sedlin may play a role in regulation of transcriptional activities of the MRG family of transcription factors via binding to PAM14.