Myogenic differentiation triggers PML nuclear body loss and DAXX relocalization to chromocentres.

The promyelocytic leukemia protein (PML) is expressed in most normal human tissues and forms nuclear bodies (NBs) that have roles in gene regulation and cellular processes such as DNA repair, cell cycle control, and cell fate decisions. Using murine C2C12 myoblasts, we demonstrate that activation of skeletal muscle differentiation results ...
in loss of PML and PML NBs prior to myotube fusion. Myotube formation was associated with marked chromatin reorganization and the relocalization of DAXX from PML NBs to chromocentres. MyoD expression was sufficient to cause PML NB loss, and silencing of PML induced DAXX relocalization. Fusion of C2C12 cells using the reptilian reovirus p14 fusogenic protein failed to disrupt PML NBs yet still promoted DAXX redistribution and loss; whereas ectopic expression of PML in differentiated cells only partially restored PML NB formation and DAXX localization at NBs. Finally, we determined that the C-terminal SUMO-interacting motif of DAXX is required for its colocalization with ATRX in heterochromatin domains during myotube formation. These data support a model in which activation of myogenic differentiation results in PML NB loss, chromatin reorganization and DAXX relocalization, and provides a paradigm for understanding the consequence of PML loss in other cellular contexts, such as during cancer development and progression.
Mesh Terms:
Amino Acid Motifs, Animals, Carrier Proteins, Cell Line, Heterochromatin, Intracellular Signaling Peptides and Proteins, Mice, Models, Biological, Muscle Development, Muscle Fibers, Skeletal, Myoblasts, Nuclear Proteins, Promyelocytic Leukemia Protein, Protein Transport
Cell Death Dis
Date: Dec. 30, 2016
Download Curated Data For This Publication
213339
Switch View:
  • Interactions 2