Myotubularin Related Protein 5 (MTMR5)

By searching an EST database for sequences related to myotubularin (MTM1), Laporte et al. (1998) identified a partial MTMR5 (myotubularin-related protein-5) cDNA and cDNAs encoding 3 other novel members of the myotubularin (MTM) protein family. They noted that the predicted MTMR5 protein lacks catalytically essential residues in the tyrosine phosphatase/DSP active site. The SET (Suvar3-9, Enhancer of zeste, trithorax) domain was originally identified as a characteristic motif in several Drosophila proteins that contribute to epigenetic mechanisms of gene regulation. The human protooncoprotein HRX also contains a SET domain. Using a yeast 2-hybrid assay with the SET domain of HRX as bait, Cui et al. (1998) isolated cDNAs encoding MTMR5, or SBF1 (SET-binding factor-1).