Effect of Cl on Tyrosinase: Complex Inhibition Kinetics and Biochemical Implication

HY Han, JR Lee, WA Xu, MJ Hahn… - Journal of …, 2007 - Taylor & Francis
HY Han, JR Lee, WA Xu, MJ Hahn, JM Yang, YD Park
Journal of Biomolecular Structure and Dynamics, 2007Taylor & Francis
Tyrosinase plays a core role in melanogenesis of the various organisms. Therefore, the
regulation of the tyrosinase activity is directly related with melanin synthesis. In this study, we
investigated the Cl−-induced inhibition of human tyrosinase and the potent role of Cl− as a
negative regulator in melanogenesis. For the inhibition kinetic studies, human tyrosinase
was differently prepared from the TXM13 melanotic cells as well as from cells that had
undergone gene transfection. We found that Cl− inhibited tyrosinase in a slope-parabolic …
Abstract
Tyrosinase plays a core role in melanogenesis of the various organisms. Therefore, the regulation of the tyrosinase activity is directly related with melanin synthesis. In this study, we investigated the Cl-induced inhibition of human tyrosinase and the potent role of Cl as a negative regulator in melanogenesis. For the inhibition kinetic studies, human tyrosinase was differently prepared from the TXM13 melanotic cells as well as from cells that had undergone gene transfection. We found that Cl inhibited tyrosinase in a slope-parabolic competitive manner and tyrosinase gene transfection into HEK293 cell significantly down-regulated the expression levels of solute carrier family 12, member 4 (potassium/chloride transporters, SLC12A7) and solute carrier family 12, member 7 (potassium/chloride transporters, SLC12A7), which are known to be Cl transporters. From the results of the inhibition kinetic studies and the Cl transporter expression level, we suggested that Cl might act as a potent regulatory factor in melanogenesis. It is worth notice that a high content of Cl exists physiologically and tyrosinase reacts sensitively to Cl in a complex interaction manner.
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