UNASSIGNED: Ultraviolet (UV) radiation is the major environmental factor that causes oxidative @entity272 . Keratins are the main constituents of @entity1 skin and have been identified as oxidative target proteins. We have recently developed a mass spectrometry (MS)-based non-invasive proteomic methodology to screen oxidative modifications in @entity1 skin keratins. Using this methodology, UV effects on @entity1853 ( @entity4508 ) oxidation in @entity1 skin keratins were investigated. The initial screening revealed that @entity4508 (259), @entity4508 (262), and @entity4508 (296) in @entity19488 were the most susceptible oxidation sites upon UVA (or UVB) irradiation of @entity1 tape-stripped skin. Subsequent liquid chromatography/electrospray ionization-MS and tandem MS analyses confirmed @entity3689 sequences and oxidation sites of tryptic peptides D(290)VDGAYMTK(298) (P1) and N(258)MQDMVEDYR(267) (P2). The relative oxidation levels of @entity3881 increased in a time-dependent manner upon UVA irradiation. @entity1882 was the most effective antioxidant for artifactual oxidation of @entity4508 residues. The relative oxidation levels of @entity3881 after UVA irradiation for 48h corresponded to treatment with 100mM @entity273 for 15min. In addition, @entity4508 (259) was oxidized by only UVA irradiation. The @entity4508 sites identified in conjunction with the current proteomic methodology can be used to evaluate @entity272 under various conditions of oxidative stress. BIOLOGICAL SIGNIFICANCE: We demonstrated that the relative @entity4508 oxidation levels in keratins directly reflected UV-induced damages to @entity1 tape-stripped skin. @entity1 skin proteins isolated by tape stripping were analyzed by MS-based non-invasive proteomic methodology. @entity4508 (259), @entity4508 (262), and @entity4508 (296) in @entity19488 were the most susceptible oxidation sites upon UV irradiation. @entity4508 (259) was oxidized by only UVA irradiation. Quantitative LC/ESI-SRM/MS analyses confirmed a time-dependent increase in the relative oxidation of target peptides ( @entity3881 ) containing these @entity4508 residues, upon UVA irradiation of isolated @entity1 skin. The relative oxidation levels of @entity3881 along with the current proteomic methodology could be applied to the assessment of oxidative stress levels in skin after exposure to sunlight.

UV irradiation-induced @entity1853 oxidation in XXXX skin keratins: Mass spectrometry-based non-invasive proteomic analysis.

@entity1 :: ('9606', 'Species') :: ['human', 'Human'] @entity3881 :: ('1423', 'Gene') :: ['P1 and P2'] @entity4508 :: ('CHEBI:16643', 'Chemical') :: ['Met'] @entity1853 :: ('MESH:D008715', 'Chemical') :: ['methionine'] @entity1882 :: ('MESH:D002084', 'Chemical') :: ['Butylated hydroxytoluene'] @entity273 :: ('MESH:D006861', 'Chemical') :: ['hydrogen peroxide'] @entity19488 :: ('3848', 'Gene') :: ['K1 keratin'] @entity272 :: ('MESH:D012871', 'Disease') :: ['skin damage'] @entity3689 :: ('D000596', 'Chemical') :: ['amino acid']
@entity1 :: (9606,Species) :: ['human']
