On January 1, a research group led by Dr. Morie Ishida (PD, Research Fellow of the Japan Society for the Promotion of Science) and Professor Mitsunori Fukuda of the Graduate School of Life Sciences, Tohoku University announced that they had succeeded in developing a new tool for visualizing melanin pigments. ..
The melanin pigment that protects the human body from harmful ultraviolet rays is synthesized in special vesicles (bags) called melanosomes that exist inside melanocytes.The melanosomes formed in the melanocytes are transferred to the cells that make up the adjacent skin, keratinocytes, where they are deposited, causing sunburn on the skin.Although much of the mechanism of melanosomal transport within melanocytes has been elucidated in the last decade, how melanosomes are transported from melanocytes to keratinocytes remains a mystery.
One of the reasons why the analysis is delayed compared to the transport of melanosomes in melanocytes is that it is difficult to efficiently observe only the melanosomes delivered to keratinocytes under a microscope.Although several tools such as antibodies for observing melanosomes in melanocytes are known, these tools could not efficiently recognize melanosomes in keratinocytes.
This time, the research group accidentally discovered the tail part of Kif1c as a protein that recognizes the inside of melanosomes (melanocore) in the process of searching for new molecules that control melanosome transport. Kif1c is a kind of kinesin molecule with a motor domain and is thought to be involved in intracellular substance transport, but Kif1c itself was not involved in melanosome transport.Therefore, we worked on the development of a new tool for visualizing melanosomes by utilizing the property of being able to specifically recognize melanosomes.As a result, we succeeded in developing a new melanosome visualization tool named M-INK (MelanocoreINteractingKif1c-tail).
This made it possible to efficiently visualize the melanosomes transferred from melanocytes to keratinocytes and observe them three-dimensionally.By making full use of this tool, it is thought that the elucidation of the molecular mechanism of melanosomes transfer from melanocytes to keratinocytes, which has been mysterious until now, will be dramatically advanced.In addition, the main target of conventional whitening cosmetics is the melanocyte side (for example, inhibition of the activity of melanin synthase), but by using the evaluation system for the amount of melanosomes in keratinocytes by M-INK, the keratinocyte side can be selected. It is expected that the development of targeted whitening cosmetics will proceed in the future.
