Functional abnormalities associated with various liver diseases lead to accumulation of toxic products (such as bilirubin in jaundice and bile acids) in blood and premature death of liver cells. One of the major determinants is the inability of the liver to properly regulate bile acid transport from blood to bile. Studies are conducted to better understand the mechanisms regulating bile acid transport. Specifically, studies are designed to determine the role of various kinases and phosphatases in the regulation of bile acid transport using primary hepatocytes, hepatic cell lines and transgenic mice. Techniques used are cell culture, transfection of cell lines, solute uptake, western blots, protein phosphorylation, Protein S-nitrosylation, etc.