The myotubularin family of phosphoinositide phosphatases includes several 
members mutated in neuromuscular diseases or associated with metabolic syndrome, 
obesity, and cancer. Catalytically dead phosphatases regulate their active 
homologs by heterodimerization and potentially represent key players in the 
phosphatase-kinase balance. Although the enzymatic specificity for 
phosphoinositides indicates a role for myotubularins in endocytosis and membrane 
trafficking, recent findings in cellular and animal models suggest that 
myotubularins regulate additional processes including cell proliferation and 
differentiation, autophagy, cytokinesis, and cytoskeletal and cell junction 
dynamics. In this review, we discuss how myotubularins regulate such diverse 
processes, emphasizing newly identified functions in a physiological and 
pathological context. A better understanding of myotubularin pathophysiology 
will pave the way towards therapeutic strategies.