Identification of poly(ADP-ribose) polymerase-1 and Ku70/Ku80 as transcriptional regulators of S100A9 gene expression

• Background: S100 proteins, a multigenic family of non-ubiquitous cytoplasmic Ca2+-binding proteins, have been linked to human pathologies in recent years. Dysregulated expression of S100 proteins, including S100A9, has been reported in the epidermis as a response to stress and in association with neoplastic disorders. Recently, we characterized a regulatory element within the S100A9 promotor, referred to as MRE that drives the S100A9 gene expression in a cell type-specific, activation- and differentiation-dependent manner (Kerkhoff et al. ( 2002) J. Biol. Chem. 277, 41879-41887). Results: In the present study, we investigated transcription factors that bind to MRE. Using the MRE motif for a pull-down assay, poly(ADP-ribose) polymerase-I (PARP-I) and the heterodimeric complex Ku70/Ku80 were identified by mass spectrometry and confirmed by chromatin immunoprecipitation. Furthermore, TPA-induced S100A9 gene expression in HaCaT keratinocytes was blocked after the pharmacologic inhibition of PARP-l with 1,5- isoquinolinediol (DiQ). Conclusion: The candidates, poly(ADP-ribose) polymerase-l (PARP-l) and the heterodimeric complex Ku70/ Ku80, are known to participate in inflammatory disorders as well as tumorgenesis. The latter may indicate a possible link between S100 and inflammation-associated cancer.

Ämnesord

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

NATURVETENSKAP  -- Biologi -- Cellbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Cell Biology (hsv//eng)

Nyckelord

activation

breast-cancer cells

c/ebp-alpha

calcium-binding proteins

dna-damage

epidermal differentiation

prostate-cancer

psoriasis

skin carcinogenesis

squamous-cell carcinoma

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)