The transition from vegetative growth to flowering is a major developmental switch in the plant cycle and the timing of flowering is very critical for reproduction of plant species. In transition to flowering in plants, Flowering locus C (FLC) is one of the crucial factors. Here, we showed How the stability and activity of FLC are regulated by sumoylation mechanism. By pull-down assay, we showed that FLC interact with E3 SUMO ligase in vitro and vivo. And we showed that FLC is sumoylated in vitro condition with AtSUMO1 protein. In transgenic plants with overexpression of FLC and inducible expression of AtSIZ1, sumo E3 ligase led to increase of FLC protein level and delayed the post-translation degradation of FLC indicating that Arabidopsis E3 sumo ligase AtSIZ1 stabilizes FLC. Also, the plants with overexpression of mutant FLC (K154R, a mutation of the sumoylation site on FLC) flowered considerably earlier than plants with overexpression of FLC but comparable with wild type indicating that sumoylation is a important part for function of FLC. Our data indicate that the sumoylation of FLC is critical for its role in the control of flowering time.

Soybean proteins are widely used for human and animal feeds worldwide. The use of soybean protein has been expanded in the food industry due to their excellent nutritional benefits. But, antinutritional and allergenic factors are present in the raw mature soybean. P34 protein, referred as Gly m Bd 30K, has been identified as a predominant immunodominant allergen. The objective of this research is to identify the genetic mode of P34 protein for the improvement of soybean cultivar with a very low level of P34 protein. Two F2 populations were developed from the cross of "Pungsannamulkong" x PI567476 and "Gaechuck2ho" x PI567476 (very low level of P34 protein). Relative amount of P34 protein was observed by Western blot analysis. The observed data for the progeny of "Pungsannamulkong" and PI567476 were 133 seeds with normal content of P34 protein and 35 seeds with very low level of P34 protein (X2=1.157, P=0.20-0.30). For the progeny of "Gaechuck#1" and PI567476, the observed data were 177 seeds with normal content of P34 protein and 73 seeds with very low level of P34 protein (X2=2.353, P=0.10-0.20). From pooled data, observed data were 310 seeds with normal content of P34 protein and 108 seeds with very low level of P34 protein (X2=0.156, P=0.50-0.70). The segregation ratio (3:1) and the Chi-square value obtained from the two populations suggested that P34 protein in mature soybean seed is controlled by a single major gene. Single gene inheritance of P34 protein was confirmed in 32 F2 derived lines in F3 seeds, which were germinated from the low level of P34 protein obtained from the cross of "Pungsannamulkong" and PI567476. These results may provide valuable information to breed for new soybean line with low level of P34 protein and identification of molecular markers linked to P34 locus.