转录辅激活因子Mediator 1调控小鼠皮肤毛发再生的作用机制研究

doi:10.35541/cjd.20210761

中华皮肤科杂志 ›› 2022, Vol. 55 ›› Issue (5): 401-407.doi: 10.35541/cjd.20210761

转录辅激活因子Mediator 1调控小鼠皮肤毛发再生的作用机制研究

张书常¹ 葛医宬¹ 赵智浩¹ 郭盼¹ 邢卫斌² 胡立志¹

¹天津医科大基础医学院病原生物学系，天津 300052；²北京大学滨海医院（天津市第五中心医院）皮肤科，天津 300450

收稿日期:2021-10-18 修回日期:2022-02-18 发布日期:2022-04-29
通讯作者: 胡立志；邢卫斌 E-mail:lizhihu@tmu.edu.cn; weibinxing@163.com
基金资助:
国家自然科学基金（81972962、81573075）

Regulatory role of the transcriptional coactivator Mediator 1 in skin hair regeneration and its mechanisms

Zhang Shuchang¹, Ge Yicheng¹, Zhao Zhihao¹, Guo Pan¹, Xing Weibin², Hu Lizhi¹

¹Department of Pathogen Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300052, China; ²Department of Dermatology, Peking University BinHai Hospital （Tianjin Fifth Central Hospital）, Tianjin 300450, China

Received:2021-10-18 Revised:2022-02-18 Published:2022-04-29
Contact: Hu Lizhi; Xing Weibin E-mail:lizhihu@tmu.edu.cn; weibinxing@163.com
Supported by:
National Natural Science Foundation of China（81972962、81573075）

摘要/Abstract

摘要： 【摘要】目的探讨转录辅激活因子Mediator 1（Med1）对小鼠皮肤毛发再生的影响及可能机制。方法将C57BL/6J品系来源的Med1flox/flox小鼠与K14-Cre小鼠交配，通过Cre-Loxp系统获得Med1表皮特异性敲除小鼠，即表达K14-Cre的Med1flox/flox小鼠（敲除组），不表达K14-Cre的Med1flox/flox小鼠即为对照组，每组3只，共同饲养8周左右行背部脱毛实验，连续12 d观察毛发再生情况。12 d后，处死两组小鼠并切取其背部脱毛和未脱毛皮肤组织，提取组织总RNA，实时定量PCR检测毛发角蛋白基因、维生素D受体/β联蛋白通路相关基因、毛囊增殖与静息状态维持相关基因的表达。制备小鼠背部脱毛和未脱毛皮肤组织石蜡切片，免疫荧光染色检测小鼠皮肤毛囊隆突部位干细胞数量。组间比较采用两独立样本t检验。结果脱毛后0 ~ 12 d，与对照组相比，敲除组小鼠脱毛区皮肤毛发再生延迟。实时定量PCR检测显示，敲除组脱毛皮肤组织中毛发角蛋白基因Ha1、Krt2-16及维生素D受体/β联蛋白通路相关基因S100a3、Dlx3、Tubb3和毛囊增殖与静息状态维持相关基因Lhx2、Sox9、Nfatc1 mRNA相对表达量（22.09 ± 12.32、2.07 ± 0.20、0.02 ± 0.01、12.36 ± 2.12、1.75 ± 0.46、0.39 ± 0.02、4.42 ± 0.76、0.44 ± 0.07）均显著低于对照组（70.53 ± 9.46、7.76 ± 0.49、0.05 ± 0.01、26.16 ± 2.96、2.60 ± 0.14、0.71 ± 0.09、11.93 ± 0.42、0.75 ± 0.04；t值分别为5.40、18.64、3.89、6.57、3.04、6.10、15.03、6.18，均P < 0.05）。免疫荧光染色显示，无论在脱毛还是未脱毛皮肤组织中，敲除组毛囊隆突部位CD34+K15+毛囊干细胞数量均远低于对照组。结论 Med1基因敲除可能通过下调维生素D受体/β联蛋白通路下游基因及毛囊增殖与静息状态维持相关基因Sox9、Nfatc1、Lhx2的表达，减少毛囊干细胞数量，导致毛囊分化障碍，毛发再生延迟。

关键词: Mediator1, 毛囊干细胞, 毛发再生, VDR/β-catenin通路, Sox9, Nfatc1, Lhx2

Abstract: 【Abstract】 Objective To investigate the effect of the transcriptional coactivator Mediator 1 （Med1） on mouse hair regeneration, and to explore potential mechanisms. Methods Med1flox/flox C57BL/6J mice were mated with K14-Cre mice, and the mice with epidermis-specific knockout of Med1 gene, namely K14-Cre-expressing Med1flox/flox mice （knockout group）, were obtained by using the Cre-Loxp system, while Med1flox/flox mice without K14-Cre expression served as control group. Mice in the two groups （3 mice in each group） were raised together for 8 weeks followed by dorsal hair removal. Hair regeneration was observed for 12 consecutive days after hair removal. After 12 days, all mice in the two groups were sacrificed, their depilated and non-depilated dorsal skin tissues were resected, and total RNA was extracted from the tissues. Real-time quantitative PCR was performed to determine the mRNA expression of hair keratin genes, vitamin D receptor/β-catenin pathway-related genes, and genes associated with maintenance of hair follicle stem cell proliferation and quiescence. Paraffin-embedded sections of depilated and non-depilated mouse skin tissues were prepared, and immunofluorescence staining was conducted to determine the number of stem cells in the hair follicle bulge. Two-independent-sample t test was used for comparisons between two groups. Results From days 0 to 12 after depilation, hair regeneration was delayed in the depilated skin area in the knockout group compared with the control group. Real-time quantitative PCR showed significantly decreased mRNA relative expression levels of hair keratin genes Ha1 and Krt2-16, vitamin D receptor/β-catenin pathway-related genes S100a3, Dlx3 and Tubb3, and genes associated with maintenance of hair follicle stem cell proliferation and quiescence including Lhx2, Sox9 and Nfatc1 in the depilated skin tissues in the knockout group （22.09 ± 12.32, 2.07 ± 0.20, 0.02 ± 0.01, 12.36 ± 2.12, 1.75 ± 0.46, 0.39 ± 0.02, 4.42 ± 0.76, 0.44 ± 0.07, respectively） compared with the control group （70.53 ± 9.46, 7.76 ± 0.49, 0.05 ± 0.01, 26.16 ± 2.96, 2.60 ± 0.14, 0.71 ± 0.09, 11.93 ± 0.42, 0.75 ± 0.04, respectively; t = 5.40, 18.64, 3.89, 6.57, 3.04, 6.10, 15.03, 6.18, respectively, all P < 0.05）. Immunofluorescence staining showed that the number of CD34+K15+ hair follicle stem cells in the hair follicle bulge in both depilated and non-depilated skin tissues was significantly lower in the knockout group than in the control group. Conclusion Med1 gene knockout may down-regulate the expression of downstream genes of the vitamin D receptor/β-catenin pathway and genes associated with maintenance of hair follicle stem cell proliferation and quiescence （Sox9, Nfatc1 and Lhx2）, and reduce the number of hair follicle stem cells, leading to hair follicle differentiation disorder and hair regeneration delay.

Key words: Mediator1, Hair Follicle Stem Cells, Hair Regeneration, VDR/β-catenin pathway, Sox-9, Nfatc1, Lhx2

张书常葛医宬赵智浩郭盼邢卫斌胡立志. 转录辅激活因子Mediator 1调控小鼠皮肤毛发再生的作用机制研究[J]. 中华皮肤科杂志, 2022,55(5):401-407. doi:10.35541/cjd.20210761

Zhang Shuchang, Ge Yicheng, Zhao Zhihao, Guo Pan, Xing Weibin, Hu Lizhi. Regulatory role of the transcriptional coactivator Mediator 1 in skin hair regeneration and its mechanisms[J]. Chinese Journal of Dermatology, 2022, 55(5): 401-407.doi:10.35541/cjd.20210761

参考文献 22

［1］	Oda Y, Hu L, Bul V, et al. Coactivator MED1 ablation in keratinocytes results in hair⁃cycling defects and epidermal alterations［J］. J Invest Dermatol, 2012,132（4）:1075⁃1083. doi: 10.1038/jid.2011.430.
［2］	Ge K, Cho YW, Guo H, et al. Alternative mechanisms by which Mediator subunit MED1/TRAP220 regulates peroxisome proliferator⁃activated receptor gamma⁃stimulated adipogenesis and target gene expression［J］. Mol Cell Biol, 2008,28（3）:1081⁃1091. doi: 10.1128/MCB.00967⁃07.
［3］	Viswakarma N, Jia Y, Bai L, et al. Coactivators in PPAR⁃regulated gene expression［J］. PPAR Res, 2010,2010:250126. doi: 10.1155/2010/250126.
［4］	Jusu S, Presley JF, Williams C, et al. Examination of VDR/RXR/DRIP205 interaction, intranuclear localization, and DNA binding in ras⁃transformed keratinocytes and its implication for designing optimal vitamin D therapy in cancer［J］. Endocrinology, 2018,159（3）:1303⁃1327. doi: 10.1210/en.2017⁃03098.
［5］	Matsui K, Oda K, Mizuta S, et al. Mediator subunit MED1 is a T3⁃dependent and T3⁃independent coactivator on the thyrotropin β gene promoter［J］. Biochem Biophys Res Commun, 2013,440（1）:184⁃189. doi: 10.1016/j.bbrc.2013.09.061.
［6］	Russo JW, Nouri M, Balk SP. Androgen receptor interaction with Mediator complex is enhanced in castration⁃resistant prostate cancer by CDK7 phosphorylation of MED1［J］. Cancer Discov, 2019,9（11）:1490⁃1492. doi: 10.1158/2159⁃8290.CD⁃19⁃1028.
［7］	Yang Y, Leonard M, Zhang Y, et al. HER2⁃driven breast tumorigenesis relies upon interactions of the estrogen receptor with coactivator MED1［J］. Cancer Res, 2018,78（2）:422⁃435. doi: 10.1158/0008⁃5472.CAN⁃17⁃1533.
［8］	Knuesel MT, Taatjes DJ. Mediator and post⁃recruitment regulation of RNA polymerase II［J］. Transcription, 2011,2（1）:28⁃31. doi: 10.4161/trns.2.1.13950.
［9］	Stumpf M, Waskow C, Krötschel M, et al. The Mediator complex functions as a coactivator for GATA⁃1 in erythropoiesis via subunit Med1/TRAP220［J］. Proc Natl Acad Sci U S A, 2006,103（49）:18504⁃18509. doi: 10.1073/pnas.0604494103.
［10］	Noguchi F, Nakajima T, Inui S, et al. Alteration of skin wound healing in keratinocyte⁃specific Mediator complex subunit 1 null mice［J/OL］. PLoS One, 2014,9（8）:e102271［2021⁃10⁃01］. doi: 10.1371/journal.pone.0102271.
［11］	Nakajima T, Inui S, Fushimi T, et al. Roles of MED1 in quiescence of hair follicle stem cells and maintenance of normal hair cycling［J］. J Invest Dermatol, 2013,133（2）:354⁃360. doi: 10.1038/jid.2012.293.
［12］	Pálmer HG, Anjos⁃Afonso F, Carmeliet G, et al. The vitamin D receptor is a Wnt effector that controls hair follicle differentiation and specifies tumor type in adult epidermis［J/OL］. PLoS One, 2008,3（1）:e1483［2021⁃10⁃01］. doi: 10.1371/journal.pone.0001483.
［13］	Shah S, Islam MN, Dakshanamurthy S, et al. The molecular basis of vitamin D receptor and beta⁃catenin crossregulation［J］. Mol Cell, 2006,21（6）:799⁃809. doi: 10.1016/j.molcel.2006.01. 037.
［14］	Giangreco A, Qin M, Pintar JE, et al. Epidermal stem cells are retained in vivo throughout skin aging［J］. Aging Cell, 2008,7（2）:250⁃259. doi: 10.1111/j.1474⁃9726.2008.00372.x.
［15］	Rittié L, Stoll SW, Kang S, et al. Hedgehog signaling maintains hair follicle stem cell phenotype in young and aged human skin［J］. Aging Cell, 2009,8（6）:738⁃751. doi: 10.1111/j.1474⁃9726.2009.00526.x.
［16］	Ibrahim L, Wright EA. The long term effect of repeated pluckings on the function of the mouse vibrissal follicles［J］. Br J Dermatol, 1978,99（4）:371⁃376. doi: 10.1111/j.1365⁃2133. 1978.tb06172.x.
［17］	Vidal VP, Chaboissier MC, Lützkendorf S, et al. Sox9 is essential for outer root sheath differentiation and the formation of the hair stem cell compartment［J］. Curr Biol, 2005,15（15）:1340⁃1351. doi: 10.1016/j.cub.2005.06.064.
［18］	Nowak JA, Polak L, Pasolli HA, et al. Hair follicle stem cells are specified and function in early skin morphogenesis［J］. Cell Stem Cell, 2008,3（1）:33⁃43. doi: 10.1016/j.stem.2008.05.009.
［19］	Horsley V, Aliprantis AO, Polak L, et al. NFATc1 balances quiescence and proliferation of skin stem cells［J］. Cell, 2008,132（2）:299⁃310. doi: 10.1016/j.cell.2007.11.047.
［20］	Keyes BE, Segal JP, Heller E, et al. Nfatc1 orchestrates aging in hair follicle stem cells［J］. Proc Natl Acad Sci U S A, 2013,110（51）:E4950⁃E4959. doi: 10.1073/pnas.1320301110.
［21］	Rhee H, Polak L, Fuchs E. Lhx2 maintains stem cell character in hair follicles［J］. Science, 2006,312（5782）:1946⁃1949. doi: 10.1126/science.1128004.
［22］	Folgueras AR, Guo X, Pasolli HA, et al. Architectural niche organization by LHX2 is linked to hair follicle stem cell function［J］. Cell Stem Cell, 2013,13（3）:314⁃327. doi: 10.1016/j.stem. 2013.06.018.

转录辅激活因子Mediator 1调控小鼠皮肤毛发再生的作用机制研究

Regulatory role of the transcriptional coactivator Mediator 1 in skin hair regeneration and its mechanisms

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