Cabbage (Brassica oleracea) is one of the world's major vegetable crops. However, the cabbage plant cannot be readily vernalized and produce seed in the tropics, whereas Chinese cabbage (Brassica campestris) can be conveniently vernalized at the seed stage. Proteins from seeds of an IPSA cabbage-Chinese cabbage somatic hybrid showing both hybrid vigour and the seed-stage vernalization characteristic were analyzed and compared with those of its two parents. 1D gel analysis indicated some differential expression of the seed proteins. Furthermore, in 2D, gel analysis, 13 differentially expressed protein spots were examined: of these ten were found to belong to the cruciferin seed storage protein complex, two were unidentifiable (no MASCOT match), and one was identified as late embryogenesis Abundant (LEA)-like protein, and was present only in the cabbage parent. This LEA-like protein in cabbage seed could therefore be implicated in interfering with the vernalization process in the tropics.

Cabbage (Brassica oleracea L.) is one of the major vegetable crops in the world. Several somatic hybrids between cabbage and Chinese cabbage have been produced. These show hybrid vigor. To identify differences in protein expression that might be relevant to hybrid characteristics of interest, proteins from leaves of a somatic hybrid and its two parents were subjected to 1D and 2D gel analyses, followed by MALDI-TOF and MS/MS of selected spots. 1D gel analysis of the leaf proteins at 14th day post-germination (14 DPG) showed very similar profiles for all three Brassicas. However, upon 2D gel analysis, several differentially expressed protein spots from leaves were discerned. Of the five differentially expressed leaf proteins examined, all the protein spots were photosynthesisrelated , including RbcS (the rubisco small subunit). It is possible that differential expression of these photosynthesis-related proteins may relate to the improved growth of the somatic hybrid.