FXYD domain of FXYD domain-containing ion transport regulator 5
FXYD domain-containing ion transport regulator 5 (FXYD5) is also called dysadherin in humans or related to ion channel (RIC) in mice. Two transcript variants have been found for this gene, and they are both predicted to encode the same protein. Dysadherin is the gamma subunit the human Na,K-ATPase and is the only member that has a large extracellular sequence of 140 amino acids. Dysadherin has been observed to be over-expressed on the surface of cells that have down regulated levels of surface E-cadherin. CCL2 (bone homing cytokine) is a protein that is highly affected by silencing dysadherin expression. Dysadherin interferes with cell adhesion via beta1 subunit interactions and is a target for an extracellular antibody drug conjugate where the antibody to dysadherin is attached to a cardiac glycoside. FXYD5 expression in mouse is mainly in the kidney, intestine, spleen, and lung. Confocal immunofluorescence microscopy of mouse kidney detected FXYD5 on basolateral membranes of connecting tubules, collecting tubules, intercalated cells of collecting duct, and on apical membranes in long thin limb of Henle loop.