May act as a transcriptional coregulator during muscle development through its interaction with SNW1. Has lost its ancestral function as a Na,K-ATPase beta-subunit. Associates with a SMAD7-transcriptional complex. Interacts with SNW1 and TOR1AIP1 (By similarity). According to PubMed:17592128, does not associate with known Na,K-ATPase alpha-subunits. Detected in nuclear envelops. Highly expressed in skeletal muscle and at a lower level in heart. Belongs to the X(+)/potassium ATPases subunit beta family.