Mortality Factor 4 Like Protein 2 (MORF4L2)

The deduced 288-amino acid protein contains a single N-terminal nuclear localization signal, a helix-loop-helix domain, a region showing similarity to Drosophila Msl3, and a C-terminal leucine zipper motif. It also has a protein kinase C phosphorylation site and a tyrosine phosphorylation site. Northern blot analysis of multiple tissues revealed ubiquitous expression of a 1.8-kb transcript. Zoo blot analysis revealed conservation of MRGX from chicken to human. Transient transfection of HeLa cells with fluorescence-tagged MRGX resulted in nuclear localization. Expression of MRGX declined slightly in normal senescent fibroblasts and increased following serum stimulation. Unlike overexpression of MORF4, overexpression of MRGX did not cause abnormal nuclear morphology or cell death.