Fig. 5.

Western blot and IP analyses of various heart specimen. (A) Comparative Western blot analysis of NC cells, embryonic, postnatal and adult heart tissue immunostained against 4E9R and Gapdh: 1) CNC cells E10.5; 2∼9) embryonic heart tissue (E10.5∼E17.5); 10) postnatal heart P8; 11) postnatal heart P15; 12) adult heart. For protein integrity the reference protein Gapdh was used as loading control. E: embryonic day, P: postnatal day, d: day. (B) Coomassie Blue stained SDS-PAGE resulting from immunoprecipitation with 4E9R antibody. The IP was performed with protein lysates of several tissue and ES cell-derived specimen at various differentiation stages. Numbers 1∼17 indicate the gel bands analyzed by nLC-ESI-MSMS. All investigated samples showed a triplet band pattern between 15 and 17 kDa except the adult heart tissue, where the lowest band is missing (indicated by the red arrow). (B’) Magnified section showing a selection of analyzed samples including adult heart tissue. Identified proteins and corresponding accession numbers are listed in Supplementary Tables S5 and S6.