Nuclear Phosphoproteomics Features the Novel Smoking Markers in Mouse Lung Tissue Following Subacute Phase Exposure to Tobacco Smoke

Abstract

Smoking is a risk factor of lung diseases including chronic obstructive pulmonary disease (COPD) and lung cancer. However, the molecular mechanisms inducing these diseases remain to be completely uncovered. In order to elucidate them, it is necessary to identify the signaling pathway activated by tobacco smoking exposure. Especially, it is important to identify nuclear phosphoproteins induced by tobacco smoking exposure because the signaling pathways are modified by phosphoproteins. This time, to identify nuclear phosphoproteins as novel smoking markers, nuclear phosphoproteimics of mouse lung tissue following tobacco smoking exposure was examined. Tobacco smoking exposure against mice was examined using the nose-only, flow-past inhalation exposure chamber system for one month. Phosphopeptides eluted from nuclear proteins of the tobacco exposured mice lungs were identified by mass spectrometry. The result showed that 77 phosphoproteins were totally identified. Among them, the semiquantitative analysis using ProteoIQ proteomic software revealed that five phosphoproteins showed the different expression patterns between control and tobacco exposure groups. Furthermore, the classification by biological functions of the identified proteins revealed that these proteins were related to inflammation, regeneration, repair, proliferation, differentiation, morphological change and nicotine or stress response. Finally, we founded advanced glycosylation end product-specific receptor (RAGE) and serine/threonine-protein kinase SNF1-like kinase 2 (SIK2) as novel smoking markers.