Raj Kumar, University of Houston (IMAGE) University of Houston Caption Raj Kumar, clinical professor of biochemistry, University of Houston College of Medicine, found a mechanism for how the protein, called Nuclear Factor of Activated T cells 5 (NFAT 5), works to regulate tonicity particularly in response to hypertonicity, an imbalance of water and solutes in cells. Credit University of Houston Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.