ADAM17 variant causes hair loss via ubiquitin ligase TRIM47–mediated degradation
Xiaoxiao Wang, Chaolan Pan, Luyao Zheng, Jianbo Wang, Quan Zou, Peiyi Sun, Kaili Zhou, Anqi Zhao, Qiaoyu Cao, Wei He, Yumeng Wang, Ruhong Cheng, Zhirong Yao, Si Zhang, Hui Zhang, Ming Li
Xiaoxiao Wang, Chaolan Pan, Luyao Zheng, Jianbo Wang, Quan Zou, Peiyi Sun, Kaili Zhou, Anqi Zhao, Qiaoyu Cao, Wei He, Yumeng Wang, Ruhong Cheng, Zhirong Yao, Si Zhang, Hui Zhang, Ming Li
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Research Article Dermatology Genetics

ADAM17 variant causes hair loss via ubiquitin ligase TRIM47–mediated degradation

Abstract

Hypotrichosis is a genetic disorder characterized by a diffuse and progressive loss of scalp and/or body hair. Nonetheless, the causative genes for several affected individuals remain elusive, and the underlying mechanisms have yet to be fully elucidated. Here, we discovered a dominant variant in a disintegrin and a metalloproteinase domain 17 (ADAM17) gene caused hypotrichosis with woolly hair. Adam17 (p.D647N) knockin mice mimicked the hair abnormality in patients. ADAM17 (p.D647N) mutation led to hair follicle stem cell (HFSC) exhaustion and caused abnormal hair follicles, ultimately resulting in alopecia. Mechanistic studies revealed that ADAM17 binds directly to E3 ubiquitin ligase tripartite motif-containing protein 47 (TRIM47). ADAM17 variant enhanced the association between ADAM17 and TRIM47, leading to an increase in ubiquitination and subsequent degradation of ADAM17 protein. Furthermore, reduced ADAM17 protein expression affected the Notch signaling pathway, impairing the activation, proliferation, and differentiation of HFSCs during hair follicle regeneration. Overexpression of Notch intracellular domain rescued the reduced proliferation ability caused by Adam17 variant in primary fibroblast cells.

Authors

Xiaoxiao Wang, Chaolan Pan, Luyao Zheng, Jianbo Wang, Quan Zou, Peiyi Sun, Kaili Zhou, Anqi Zhao, Qiaoyu Cao, Wei He, Yumeng Wang, Ruhong Cheng, Zhirong Yao, Si Zhang, Hui Zhang, Ming Li

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Figure 4

ADAM17 (p.D647N) variant decreases its protein stability owing to enhanced auto-ubiquitination.

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ADAM17 (p.D647N) variant decreases its protein stability owing to enhan...
(A) Immunohistochemical staining showed that the expression of ADAM17 in patients’ hair follicles (HFs) was significantly lower than that in normal controls. Scale bar, 300 μm (n = 8 biological replicates of normal controls; n = 8 technical replicates of patient III:1). (B) ADAM17 protein level in the scalp tissues of patients was lower than that in the controls. (n = 6 biological replicates of controls; n = 6 technical replicates of patient III:1.) (C) No significant alteration detected in the mRNA levels of ADAM17. (n = 4 biological replicates of controls; n = 4 technical replicates of patient III:1.) (D) Adam17 protein level in HFs of Adam17D647N/D674N mice was lower than that in wild-type (WT) mice. Left scale bar, 100 μm; right scale bar, 50 μm. (n = 28–32 technical replicates.) (E) Adam17 protein level in skin tissues was significantly reduced in Adam17D647N/D674N mice compared with the WT mice. (n = 3 biological replicates.) (F) No significant changes were observed in the mRNA levels of Adam17 between ADAM17D647N/D674N and WT mice. (n = 6 biological replicates.) (G) Cycloheximide (CHX) chase analysis showed that ADAM17 (p.D674N) mutation induced rapid degradation of ADAM17 in HaCaT cells. (H) ADAM17 (p.D647N) mutation resulted in heightened degradation of ADAM17 though proteasome pathway in HaCaT cells. (I) ADAM17 (p.D647N) mutation had no bearing on the degradation of ADAM17 through the autophagy pathway in HaCaT cells. (J) ADAM17 (p.D647N) mutation resulted in heightened ubiquitination and subsequent degradation of ADAM17 via the proteasomal pathway. All experiments were repeated 3 times. Results were expressed as mean ± SD; *P < 0.05; **P < 0.01; ***P < 0.001; unpaired 2-tailed t test (B and C); 1-way ANOVA (E and F); Mann-Whitney test (A).