| Project/Area Number |
12670843
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Dermatology
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| Research Institution | St. Marianna University School of Medicine |
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Principal Investigator |
MIZOGUCHI Masako St. Marianna Univ., Dept of Dermatol, Professor, 医学部, 教授 (30010250)
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| Co-Investigator(Kenkyū-buntansha) |
KAWA Yoko St. Marianna Univ., Dept of Dermatol, Assistant, 医学部, 助手 (10082273)
KASHIMA Masako St. Marianna Univ., Dept of Dermatol, Lecturer, 医学部, 講師 (50169421)
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| Project Period (FY) |
2000 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2001: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2000: ¥2,100,000 (Direct Cost: ¥2,100,000)
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| Keywords | differentiation of mealnocytes / apoptosis / all-trans retionic acid (ATRA) / neural crest cell line / MITF / apoptosis / 神経冠由来メラノサイト培養株 / All trans retinoic acid (ATRA) |
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| Research Abstract |
The effects of all-rram retinoic acid (ATRA) on the differentiation and proliferation of immature melanocyte precursors was studied. NCC-melb4 cells are an immortal cloned cell line established from mouse neural crest cells (NCC) using a single-cell cloning method. These cells were positive for tyrosinase-related protein-1 (TYRP1), tyrosinase-related protein-2 (TYRP2) and KIT, but were negative for tyrosinase and had no DOPA reaction. They contained only stage 1 melanosomes without any melanosomes in more advanced stages. After treatment with ATRA for 72 hr many of the cells became tyrosinase- and DOPA-reaction-positive, changed from polygonal to dendritic in shape, and had stage II to IV melanosomes. These findings indicate that treatment with ATRA induced the differentiation of NCC-melb4 cells. RT-PCR analysis revealed a marked increase in expression of microphthalmia-associated transcription factor (MITF) mRNA after ATRA treatment suggesting that MITF may be the key molecule in this event. Enhanced expression of protein kinase C (PKC) α following treatment with ATRA was also demonstrated. The proliferation of NCC-melb4 cells was inhibited by ATRA in a dose-dependent manner. Increased apoptosis after ATRA treatment was observed by electron microscopy, the TUNEL method and by flow cytometry. Electron microscopy showed that apoptotic cells contained melanosomes of advanced stages, suggesting that mature melanocytes may tend to undergo apoptosis after ATRA treatment. This study provides important clues towards understanding the roles and working mechanisms of retinoic acids in melanocyte development and melanogenesis.
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