Absence of TRP-2 in melanogenic melanocytes of human hair
Absence of TRP-2 in melanogenic melanocytes of human hair
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DOI：
10.1111/j.1600-0749.2004.00170.x
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发表时间：
2004-10-01
期刊：
影响因子：
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通讯作者：
Bernard, BA
中科院分区：
文献类型：
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作者：
Commo, S;Gaillard, O;Bernard, BA
皮肤和头发的颜色主要取决于黑素细胞的活性。已经鉴定了许多参与黑素细胞功能的蛋白质，包括pMel-17、Mitf-M、Sox 10、酪氨酸酶、酪氨酸酶相关蛋白-1（TRP-1）和-2（TRP-2）。在头发中，黑素生成活性仅发生在头发周期的生长期阶段。为了评估一些已知的黑素生成蛋白在人类毛发色素沉着中的意义，我们进行了免疫组织化学研究，以揭示pMel-17、Mitf-M、酪氨酸酶、TRP-1和TRP-2在不同种族来源的真黑素棕色和黑色毛发生长初期的活跃球黑素细胞中的表达，例如棕色高加索人、黑色亚洲人和非洲人的毛发。标签进行了比较，在高加索人和非洲头皮表皮（毛囊间表皮）黑色素细胞观察。我们发现，尽管pMel-17、TRP-1和TRP-2在表皮黑素细胞中表达，而与头皮表皮的种族来源和黑素含量无关，但Mitf-M和酪氨酸酶表达仅在着色表皮（例如非洲头皮）中清楚地证明。关于人的头发，pMel-17、Mitf-M、酪氨酸酶和TRP-1以类似的方式在棕色和黑色头发的活性球黑素细胞中检测到。相反，出乎意料的是，TRP-2不能在毛球黑色素细胞中检测到，无论头发颜色和种族起源如何。通过蛋白质印迹分析进一步证实TRP-2的缺乏。对毛球mRNA进行的逆转录-聚合酶链反应（RT-PCR）表明，Mitf-M，酪氨酸酶和TRP-1扩增物信号很容易检测到，而TRP-2扩增物信号几乎检测不到。此外，在毛球中未检测到Sox 10。总之，我们的研究结果表明，TRP-2的检测水平的情况下，是由于转录控制在人类真黑质毛球的活性黑素细胞。根据TRP-2在棕色和黑色毛球的产生黑色素的黑素细胞中的缺乏，必须考虑真黑素生成以及棕色和黑色不需要人头发中的TRP-2表达。
Skin and hair colour mostly depend on the activity of melanogenic melanocytes. Numerous proteins involved in melanocyte function have been identified including pMel-17, Mitf-M, Sox10, tyrosinase, tyrosinase related proteins-1 (TRP-1) and -2 (TRP-2). In the hair, melanogenic activity occurs only during the anagen phase of the hair cycle. In order to evaluate the implications of some known melanogenic proteins in human hair pigmentation, we performed immunohistochemical studies to reveal the expression of pMel-17, Mitf-M, tyrosinase, TRP-1 and TRP-2 in active bulb melanocytes of eumelanic brown and black anagen hairs of different ethnic origins, e.g. brown Caucasian, black Asian and African hairs. The labelling was compared with that observed in Caucasian and African scalp epidermis (interfollicular epidermis) melanocytes. We found that while pMel-17, TRP-1 and TRP-2 were expressed in epidermal melanocytes irrespective of ethnic origin and melanin content of the scalp epidermis, Mitf-M and tyrosinase expression were clearly evidenced only in pigmented epidermis, e.g. African scalps. Regarding human hair, pMel-17, Mitf-M, tyrosinase and TRP-1 were detected in a similar manner in active bulb melanocytes of brown and black hairs. In contrast and unexpectedly, TRP-2 could not be detected in hair bulb melanocytes, whatever the hair colour and ethnic origin. The lack of TRP-2 was further confirmed by western blot analyses. Reverse transcriptase-polymerase chain reaction (RT-PCR) performed on hair bulb mRNA demonstrated that Mitf-M, tyrosinase and TRP-1 amplimer signals were easily detected, whereas the TRP-2 amplimer signal was barely detectable. Furthermore Sox10 was not detected in hair bulb. Altogether our results suggest that the absence of detectable level of TRP-2 is due to transcriptional control in active melanocytes of human eumelanic hair bulbs. According to the absence of TRP-2 in melanin-producing melanocytes of brown and black hair bulbs, one must consider that eumelanogenesis as well as brown and black colour do not require TRP-2 expression in human hair.