(The) role of FAM86A in melanogenesis and skin cancer

다국어 초록 (Multilingual Abstract)

Post-translational modifications (PTMs) refer to the process in which specific groups are added to a protein after its synthesis, regulating its function, interaction, localization, and stability. This process plays a crucial role in controlling various cellular functions and has emerged as a promising field for disease treatment. The enzyme FAM86A, studied in this paper, is a non-histone protein lysine methyltransferase known to methylate lysine 525 of EEF2.
Chapter 1 investigates the relationship between FAM86A and melanogenesis. The study focuses on the correlation between human MITF and human FAM86A in human cell lines. Melanin secretion was found to be higher in the human cell lines MALME-3M and MNT1, confirmed by melanin content assays, and visually, the solution appeared close to black. Furthermore, increased levels of p-MITF and Tyrosinase were observed compared to other cell lines. When FAM86A and MITF were overexpressed together in each cell line, immunofluorescence analysis showed that overexpression of FAM86A in MALME-3M and MNT1 cells reduced the translocation of MITF to the nucleus. Additionally, melanin contents assay and luciferase assay demonstrated that higher expression levels of FAM86A led to a decrease in melanin content.
Chapter 2 investigates the association between FAM86A and squamous cell carcinoma (SCC). RNA sequencing data revealed that when FAM86A was overexpressed, genes related to DNA repair and immune response were downregulated. In contrast, when FAM86A was knocked out, genes related to DNA repair and immune response were upregulated. Animal experiments confirmed that the incidence of SCC was highest in FAM86A transgenic mice, followed by wild-type mice and FAM86A knock-out mice. Inflammatory cytokines TNF-α and IL-1β were also found to be elevated in FAM86A transgenic mice, as measured by ELISA. Furthermore, comet assays showed increased DNA damage in FAM86A transgenic mice. These findings suggest that higher levels of FAM86A promote the development of SCC.
Combining the results of Chapters 1 and 2, it was demonstrated that FAM86A regulates melanogenesis in human cells and influences SCC incidence based on its expression level. Therefore, this study suggests that FAM86A could be an important target for treating diseases related to melanogenesis and SCC.

목차 (Table of Contents)

• Abstract 1
• Chapter Ⅰ. The role of FAM86A in melanogenesis 3
• 1. Introduction 3
• 2. Materials and Methods 6
• 2.1 Materials 6
• 2.2 Basic Local alignment Search Tool (BLAST) 7
• 2.3 Cell culture 7
• 2.4 Melanin contents assay 7
• 2.5 Western blotting analysis 8
• 2.6 Overexpression of FAM86A and MITF 9
• 2.7 Immunofluorescence staining 9
• 2.8 Luciferase activity assay 10
• 2.9 Statistical analysis 11
• 3. Results 12
• 3.1 Comparison of FAM86A and MITF gene sequences between mouse and human 12
• 3.2 Melanogenesis and mechanisms in human skin cells 13
• 3.3 Location change of MITF depending on FAM86A 17
• 3.4 Changes in melanin contents according to the expression level of FAM86A 21
• 4. Conclusion and discussion 25
• Chapter Ⅱ. The role of FAM86A in skin cancer 28
• 1. Introduction 28
• 2. Materials and Methods 32
• 2.1 Materials 32
• 2.2 QuantSeq 3' mRNA sequencing 32
• 2.3 Animals 33
• 2.4 DMBA/TPA mouse model 34
• 2.5 Hematoxylin and eosin stain 35
• 2.6 Enzyme-linked immunosorbent assay (ELISA) 35
• 2.7 Comet assay 35
• 2.8 Statistical analysis 36
• 3. Results 37
• 3.1 Gene expression change in FAM86A transgenic mouse 37
• 3.2 Gene expression change in FAM86A Knock-out mouse 42
• 3.3 Differences in Squamous cell carcinoma formation according to the expression changes of FAM86A 47
• 3.4 Differences in cytokine and DNA damage according to the expression changes of FAM86A 50
• 4. Conclusion and discussion 54
• References 57
• 국문요약 (초록) 69