XUE Chunlei, LU Xiaoping, HAN Pingan, ZHANG Kunming, ZHANG Ruixia, DONG Jing
Sorghum-sudangrass hybrids are annual gramineous forage crops with intergrated excellent parental traits. Their heterosis is particularly prominent, but the molecular mechanism of the heterosis is not yet very clear. To reveal the molecular mechanism, the mature embryos of sorghum-sudangrass hybrids and their parents are analyzed by the Label free mass spectrometry and the bioinformatics methods based on proteomics in this study. 124 differentially expressed proteins are identified, among which 48 are additive accumulation proteins, accounting for 38.71% of the total proteins. 19 and 29 of them are up-regulated proteins and down-regulated proteins, respectively. 76 of them are non-additive accumulation proteins, accounting for 61.29% of the total proteins. 29 proteins are of the above-high-parent expression, with the greatest proportion among the non-additive accumulation expression patterns. Followed by the high-parent expression patterns(18 proteins), the low-parent expression patterns (14 proteins), the below-low-parent expression patterns(10 proteins). Besides, there are 5 proteins which do not belong to the above four kinds of protein expression patterns. Therefore, non-additive proteins play especially dominant roles in the heterosis of the mature embryo of sorghum-sudangrass hybrids. Additive and non-additive accumulation proteins cover multiple functional groups, which involve the stress response, the carbohydrate metabolism, the transcriptional regulation, the development regulation, the signal transduction, the protein metabolism and others.