DTL facilitates the Fanconi anemia pathway for ultraviolet-induced DNA repair in retinal pigment epithelial cells

Jiuchun Guo,Qianqian Guo,Jie Pan

doi:10.32604/biocell.2021.015785

Abstract

The excessive energy of light, especially the invisible rays with lower wavelength, is basically absorbed by retinal pigment epithelium (RPE) and usually causes DNA damage. The molecular mechanism behind DNA damage repair response to this frequent stress in RPE is not clearly understood. In this study, we determined that the Fanconi anemia (FA) pathway was activated in human RPE ARPE-19 cells after ultraviolet (UV) B and C treatment. Moreover, immunoprecipitation (IP) of FANCD2 indicated that denticleless E3 ubiquitin protein ligase homolog (DTL) closely interacted with FANCD2. Knockdown of DTL weakened the activity of the FA pathway in ARPE-19 cells responding to UV treatment. Finally, the DTL promoter was incubated with a biotin-labeled probe and pulled down by streptavidin beads followed by the genomic DNA sonication. p53 was indicated by mass spectrum and further determined by chromatin IP assay. Taken together, our results demonstrated that DTL regulated by p53 could activate the FA pathway for UV-induced DNA damage repair in retinal pigment epithelial cells.

Highlights

In the normal visible light or sunshine, only a small part reaching the retina is attributed to the sense of sight, while the rest of it is usually absorbed by the retinal pigment epithelium (RPE)
Transcription activity of denticleless E3 ubiquitin protein ligase homolog (DTL) was enhanced by p53 in UV treated ARPE-19 cells we studied the mechanism of DTL transcription regulated by UVB
In the S phase, chromatin licensing and DNA replication factor 1 (CDT1) was recognized by DTL and further degraded by the E3 ubiquitin ligase complex of CUL4-DDB1-DTL

Summary

Introduction

In the normal visible light or sunshine, only a small part reaching the retina is attributed to the sense of sight, while the rest of it is usually absorbed by the retinal pigment epithelium (RPE). RPE is subjected to greater energy from the light with lower wavelengths, which causes adverse effects on the photoreceptors and vision (Patton et al, 1999). Ultraviolet (UV) radiation whose spectrum less than 400 nm can be further divided into three subtypes UVA (315–400 nm), UVB (280–315 nm and UVC (100–280 nm). The irradiation of UVB and UVC is directly deleterious to DNA through photochemical modification. The covalently bonded pyrimidine dimers are generated by UV-derived photons and cause the DNA strand twist to interfere with the process of DNA replication and transcription (Roy, 2017). DNA double-strand breaks (DSBs) and interstrand crosslinking (ICL) can be induced by UV lesions (Han et al, 2015; Yin et al, 2017)

Methods

Results

Conclusion