The heterozygous variant c. 1574C > G (p.T525R) of SASH1 gene can promote the increase of melanin synthesis

doi:10.11958/20221703

Tianjin Medical Journal ›› 2023, Vol. 51 ›› Issue (7): 756-761.doi: 10.11958/20221703

• Clinical Research • Previous Articles Next Articles

The heterozygous variant c. 1574C > G (p.T525R) of SASH1 gene can promote the increase of melanin synthesis

CHEN Hongyu¹^,²(), ZHANG Jing², ZENG Zhen¹^,², YANG Pingping¹^,², XIONG Yu¹^,², ZHANG Miao³, ZHOU Ding’an²^,^△()

1 School of Medical Laboratory Science, Guizhou Medical University, Guiyang 550004, China
2 Clinical Research Center, the Affiliated Hospital of Guizhou Medical University
3 Department of Endocrinology, the Affiliated Hospital of Guizhou Medical University

Received:2022-10-27 Revised:2023-02-16 Published:2023-07-15 Online:2023-07-18
Contact: ^△ZHOU Ding’an E-mail:460318918@qq.com

CHEN Hongyu, ZHANG Jing, ZENG Zhen, YANG Pingping, XIONG Yu, ZHANG Miao, ZHOU Ding’an. The heterozygous variant c. 1574C > G (p.T525R) of SASH1 gene can promote the increase of melanin synthesis[J]. Tianjin Medical Journal, 2023, 51(7): 756-761.

Abstract

Abstract:

Objective To report a case of dyschromatosis universalis hereditaria (DUH) caused by the variant site of c.1574C>G (p.T525R) of SASH1 gene and discuss the effect of mutation on melanin synthesis by functional experiments in vitro. Methods DNA was extracted from the peripheral blood of the proband and his parents, and pathogenic genes were identified by whole-exome sequencing and Sanger sequencing. Bioinformatics was used to analyze the harmful gene variant site. Mouse melanoma cell B16 was used as the cell model, and Western blot assay was used to analyze the effect of SASH1 gene c.1574C>G (p.T525R) variation on the expression of microphthalmia-associated transcription factor (MITF) and Tyrosinase proteins. In vitro melanin quantification experiment was used to analyze the effect of this variant site on melanin synthesis in human melanoma cells SK-MEL-1 and B16 cells. Results Gene sequencing results showed that the proband was detected SASH1 gene c.1574C>G (p.T525R) mutation. Bioinformatics analysis showed that the variant had a high probability affecting protein structure and function. Western blot results showed that this variant site up-regulated the expression levels of MITF and Tyrosinase, which were the most critical in melanin synthesis. This variation analyzed by in vitro melanin quantification can increase the melanin synthesis in B16 and SK-MEL-1 cells. Conclusion The heterozygous variant c.1574C>G (p.T525R) of SASH1 gene is associated with DUH, and this mutation can promote the increase of melanin synthesis in melanoma cells.

Key words: melanins, microphthalmia-associated transcription factor, dyschromatosis universalis hereditaria, SASH1 gene

CLC Number:

R394.3

Figures/Tables 8

Fig.1 Clinical manifestations of the proband

Fig.2 Sanger sequencing of SASH1 c.1574C>G of the proband and his parents

Fig. 3 PolyPhen-2 predicted the effect of T525R-SASH1 mutation on the structure and function of the protein

Fig. 4 MEGA7 predicted that the conserved nature of Thr525 locus in different species

Fig.5 Confocal microscopy showed the localization of SASH1 in PIG1 cells (Immunofluorescence staining ×200)

Fig.6 T525R-SASH1 overexpression increased MITF and Tyrosinase expression in B16 cells

Fig.7 T525R-SASH1 over expression increased melanin synthesis in melanoma cells

Tab.1 Comparison of expression levels of MITF and Tyrosinase proteins between the three groups

组别	MITF	Tyrosinase
空白对照组	0.97±0.02	0.16±0.02
WT-SASH1组	1.22±0.08^a	0.48±0.03^a
T525R-SASH1组	1.76±0.04^ab	1.12±0.1^ab
F	107.884^＊＊	179.575^＊＊

References 15

[1]	ALDOKHAYEL S, NOUF A, KHALID A, et al. A novel mutation in ABCB6 associated with dyschromatosis universalis hereditaria in a Saudi family[J]. JAAD Case Rep, 2021, 19:97-99. doi:10.1016/j.jdcr.2021.11.017.
[2]	ZELLER C, HINZMANN B, SEITZ S, et al. SASH1:a candidate tumor suppressor gene on chromosome 6q24.3 is downregulated in breast cancer[J]. Oncogene, 2003, 22(19):2972-2983. doi:10.1038/sj.onc.1206474.
[3]	XING Q H, WANG M T, CHEN X D, et al. A gene locus responsible for dyschromatosis symmetrica hereditaria (DSH) maps to chromosome 6q24.2-q25.2[J]. Am J Hum Genet, 2003, 73(2):377-382. doi:10.1086/377007.
[4]	ZHOU D, WEI Z, DENG S, et al. SASH1 regulates melanocyte transepithelial migration through a novel Gαs-SASH1-IQGAP1-E-Cadherin dependent pathway[J]. Cell Signal, 2013, 25(6):1526-1538. doi:10.1016/j.cellsig.2012.12.025.
[5]	ZHOU D, WEI Z, KUANG Z, et al. A novel P53/POMC/Gαs/SASH1 autoregulatory feedback loop activates mutated SASH1 to cause pathologic hyperpigmentation[J]. J Cell Mol Med, 2017, 21(4):802-815. doi:10.1111/jcmm.13022.
[6]	ZHOU D, KUANG Z, ZENG X, et al. p53 regulates ERK1/2/CREB cascade via a novel SASH1/MAP2K2 crosstalk to induce hyperpigmentation[J]. J Cell Mol Med, 2017, 21(10):2465-2480. doi:10.1111/jcmm.13168.
[7]	WU N, TANG L, LI X, et al. Identification of a novel mutation in SASH1 gene in a Chinese family with dyschromatosis universalis hereditaria and genotype-phenotype correlation analysis[J]. Front Genet, 2020, 11:841. doi:10.3389/fgene.2020.00841.
[8]	ZHONG W L, WANG H J, LIN Z M, et al. Novel mutations in SASH1 associated with dyschromatosis universalis hereditaria[J]. Indian J Dermatol Venereol Leprol, 2019, 85(4):440. doi:10.4103/ijdvl.IJDVL_360_17.
[9]	CAO L, ZHANG R, YONG L, et al. Novel missense mutation of SASH1 in a Chinese family with dyschromatosis universalis hereditaria[J]. BMC Med Genomics, 2021, 14(1):168. doi:10.1186/s12920-021-01014-w.
[10]	CUI H, GUO S, HE H, et al. SASH1 promotes melanin synthesis and migration via suppression of TGF-β1 secretion in melanocytes resulting in pathologic hyperpigmentation[J]. Int J Biol Sci, 2020, 16(7):1264-1273. doi:10.7150/ijbs.38415.
[11]	LIU J W, HABULIETI X, WANG R R, et al. Two novel SASH1 mutations in Chinese families with dyschromatosis universalis hereditaria[J]. J Clin Lab Anal, 2021, 35(6):e23803. doi:10.1002/jcla.23803.
[12]	ARAKI Y, OKAMURA K, SAITO T, et al. Five novel mutations in SASH1 contribute to lentiginous phenotypes in Japanese families[J]. Pigment Cell Melanoma Res, 2021, 34(2):174-178. doi:10.1111/pcmr.12930.
[13]	HWANG Y S, KIM Y J, KIM M O, et al. Cannabidiol upregulates melanogenesis through CB1 dependent pathway by activating p38 MAPK and p42/44 MAPK[J]. Chem Biol Interact, 2017, 273:107-114. doi:10.1016/j.cbi.2017.06.005.
[14]	LIM J W, HA J H, JEONG Y J, et al. Anti-melanogenesis effect of dehydroglyasperin C through the downregulation of MITF via the reduction of intracellular cAMP and acceleration of ERK activation in B16F1 melanoma cells[J]. Pharmacol Rep, 2018, 70(5):930-935. doi:10.1016/j.pharep.2018.02.024.
[15]	RACHMIN I, OSTROWSKI S M, WENG Q Y, et al. Topical treatment strategies to manipulate human skin pigmentation[J]. Adv Drug Deliv Rev, 2020, 153:65-71. doi:10.1016/j.addr.2020.02.002.

The heterozygous variant c. 1574C > G (p.T525R) of SASH1 gene can promote the increase of melanin synthesis

Cite this article

RichHTML

PDF (PC)

Knowledge

Abstract

share this article

Figures/Tables 8

References 15

Related Articles 1

Recommended Articles

Metrics

Comments