Microarray as high throughput tool for tyrosinase gene expression analysis

Since ancient times, a face with fair skin is considered as a sign of beauty and the demand for young, healthy, bright and fair skin has created a whitening cosmetics market. The color of human skin and hair established through a number of factors. Melanogenesis i.e. the biosynthesis of melanin is the major factor. It is a multistage process involving melanin synthesis in special organelles called melanosomes of melanocytes and melanin transport to keratinocytes. The actual color of the skin is determined by the distribution pattern of the melanin by the melanocytes. Tyrosinase is considered as key enzyme of melanogenesis as it plays a central role in biosynthetic pathway of melanin and catalyzes the first two steps: the hydroxylation of monophenol to diphenol and the oxidation of diphenol to quinine [1-4]. Abnormal deposition or irregular distribution of melanin causes hyper pigmentary disorders such as melasma, freckles and age spots. One of the major causes of hyper pigmentation is probably UV light. However, the skin darkening can be restrained, at least to some extent, by deactivating the enzyme tyrosinase [5]. So, in order to treat hyper pigmentation and the quest for skin whitening move forward the scientists of all over the world to search inhibitors of enzyme tyrosinase. Although a number of ingredients from natural sources with an inhibitory effect on melanogenesis have been studied in order to treat hyper pigmentation as well as developed as cosmetic agents to make skin white. But many of them find associated with several side effects Hence research is going on for the elucidation of tyrosinase inhibitors with less or no side effects [6,7]. Traditionally, the molecules having antityrosinase activity have been elucidated by using different time consuming and labour intensive experiments. But, with the advancement in technology and the introduction of high throughput techniques make it easier for the biotechnologists to screen many compounds at a time for its inhibitory activity against tyrosinase. One of the techniques of high throughput screening of a molecule is microarray It is a powerful tool used for profiling gene expression, proteinprotein and protein-ligand interaction in high throughput [8]. So it is possible with microarray to screen various compounds as tyrosinase inhibitors. Besides traditional and manual approaches of elucidation and development of tyrosinase inhibitors, here in this review we will focus the importance of the use of high throughput techniques with special emphasis on microarray.