Figure 1.

A and B, The two-dimensional gel fractionation of the total proteins of mature Jack (A) and SP− (B) seeds is shown. Note that abundant storage proteins in Jack seeds are absent in the SP− seeds, which accumulate a few alternative proteins that account for a large fraction of the total seed proteins. C, The spot selection for excision from the SP− seeds is shown to identify protein spots with changes in comparison with Jack. The spots were excised, digested with trypsin, and processed by tandem mass spectroscopy to identify the proteins. The spot numbers on the gel correspond to the identification and mass spectroscopy data outlined in Supplemental Table S1. IEF, Isoelectric focusing.