Apr 16, 2014

Significance of the melanocortin 1 receptor in the DNA damage response of human melanocytes to ultraviolet radiation

Pigment Cell & Melanoma Research
Viki B SwopeZalfa A Abdel-Malek

Abstract

Activation of the melanocortin 1 receptor (MC1R) by α-melanocortin (α-MSH) stimulates eumelanin synthesis and enhances repair of ultraviolet radiation (UV)-induced DNA damage. We report on the DNA damage response (DDR) of human melanocytes to UV and its enhancement by α-MSH. α-MSH up-regulated the levels of XPC, the enzyme that recognizes DNA damage sites, enhanced the UV-induced phosphorylation of the DNA damage sensors ataxia telangiectasia and Rad3-related (ATR) and ataxia telangiectasia mutated (ATM) and their respect-ive substrates checkpoint kinases 1 and 2, and increased phosphorylated H2AX (γH2AX) formation. These effects required functional MC1R and were absent in melanocytes expressing loss of function (LOF) MC1R. The levels of wild-type p53-induced phosphatase 1 (Wip1), which dephosphorylates γH2AX, correlated inversely with γH2AX. We propose that α-MSH increases UV-induced γH2AX to facilitate formation of DNA repair complexes and repair of DNA photoproducts, and LOF of MC1R compromises the DDR and genomic stability of melanocytes.

  • References54
  • Citations27

References

  • References54
  • Citations27

Citations

Mentioned in this Paper

Melanocyte
H2AFX gene
ACTH (1-13)NH2
H2AFX wt Allele
MC1R Protein
DNA Repair
Complex (molecular entity)
Genomic Stability
Base Excision Repair
Response to DNA Damage Stimulus

Related Feeds

Ataxia telangiectasia (MDS)

Ataxia telangiectasia is a rare neurodegenerative diseases caused by defects in the ATM gene, which is involved in DNA damage recognition and repair pathways. Here is the latest research on this autosomal recessive disease.

Cell Checkpoints & Regulators

Cell cycle checkpoints are a series of complex checkpoint mechanisms that detect DNA abnormalities and ensure that DNA replication and repair are complete before cell division. They are primarily regulated by cyclins, cyclin-dependent kinases, and the anaphase-promoting complex/cyclosome. Here is the latest research.

Ataxia telangiectasia

Ataxia telangiectasia is a rare neurodegenerative diseases caused by defects in the ATM gene, which is involved in DNA damage recognition and repair pathways. Here is the latest research on this autosomal recessive disease.