{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T01:18:10Z","timestamp":1778807890089,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,12]],"date-time":"2020-11-12T00:00:00Z","timestamp":1605139200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Science and Technology Agency (JST) CREST","award":["JPMJCR17H4"],"award-info":[{"award-number":["JPMJCR17H4"]}]},{"name":"Grant-in-Aid for Young Scientists from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan","award":["20K15739"],"award-info":[{"award-number":["20K15739"]}]},{"name":"Grant-in-Aid for Scientific Research (B) from MEXT of Japan","award":["19H03220"],"award-info":[{"award-number":["19H03220"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Melanin incorporated into keratinocytes plays an important role in photoprotection; however, abnormal melanin accumulation causes hyperpigmentary disorders. To understand the mechanism behind the accumulation of excess melanin in the skin, it is essential to clarify the spatial distribution of melanosomes or melanin in the epidermis. Although several markers have been used to detect melanosomes or melanin, no suitable markers to determine the precise localization of melanin in the epidermis have been reported. In this study, we showed that melanocore-interacting Kif1c-tail (M-INK), a recently developed fluorescent probe for visualizing mature melanosomes, binds to purified melanin in vitro, and applied it for detecting melanin in human skin tissues. Frozen skin sections from different phototypes were co-stained for the hemagglutinin (HA)-tagged M-INK probe and markers of melanocytes or keratinocytes, and a wide distribution of melanin was observed in the epidermis. Analysis of the different skin phototypes indicated that the fluorescent signals of HA-M-INK correlated well with skin color. The reconstruction of three-dimensional images of epidermal sheets enabled us to observe the spatial distribution of melanin in the epidermis. Thus, the HA-M-INK probe is an ideal tool to individually visualize melanin (or melanosome) distribution in melanocytes and in keratinocytes in skin tissues.<\/jats:p>","DOI":"10.3390\/ijms21228514","type":"journal-article","created":{"date-parts":[[2020,11,12]],"date-time":"2020-11-12T10:00:32Z","timestamp":1605175232000},"page":"8514","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Novel Method for Visualizing Melanosome and Melanin Distribution in Human Skin Tissues"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6950-781X","authenticated-orcid":false,"given":"Chikako","family":"Yoshikawa-Murakami","sequence":"first","affiliation":[{"name":"KOS\u00c9 R&amp;D France, KOS\u00c9 Corporation, 5 Avenue Lionel Terray, 69330 Meyzieu, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuki","family":"Mizutani","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo 114-0005, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akemi","family":"Ryu","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo 114-0005, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8002-0850","authenticated-orcid":false,"given":"Eiji","family":"Naru","sequence":"additional","affiliation":[{"name":"Research Laboratories, KOS\u00c9 Corporation, 48-18 Sakae-cho, Kita-ku, Tokyo 114-0005, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5835-929X","authenticated-orcid":false,"given":"Takashi","family":"Teramura","sequence":"additional","affiliation":[{"name":"KOS\u00c9 R&amp;D France, KOS\u00c9 Corporation, 5 Avenue Lionel Terray, 69330 Meyzieu, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuta","family":"Homma","sequence":"additional","affiliation":[{"name":"Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8620-5853","authenticated-orcid":false,"given":"Mitsunori","family":"Fukuda","sequence":"additional","affiliation":[{"name":"Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1034\/j.1600-0625.12.s2.1.x","article-title":"Melanosome transfer to and translocation in the keratinocyte","volume":"12","author":"Boissy","year":"2003","journal-title":"Exp. 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