Biotin-modified cardiac-hypertrophy-associated piRNA (CHAPIR) pulldown proteins

PIWI-interacting RNAs (piRNAs) are abundantly expressed during cardiac hypertrophy development, but their influence on pathological hypertrophy and the underlying mechanisms remains to be elucidated. Here, we identified a cardiac-hypertrophy-associated piRNA (CHAPIR), and we found that it regulates pathological hypertrophy. To investigate the molecular mechanisms by which CHAPIR regulates cardiomyocyte hypertrophy, we transfected the biotinylated CHAPIR into cardiomyocytes and performed streptavidin bead pull down assay. The CHAPIR pull-down materials and its control were resolved using SDS-PAGE gel and stained with coomassie blue. Then the entire gel lanes of the CHAPIR pull-down materials and its control were excised and send for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis.