Figure 1.
Superior spikelets (SS) and inferior spikelets (IS) in rice.
A: Developmental changes in representative SS and IS B: Grain weight of SS and IS. Experiments were repeated 6 times. Error bars represent standard errors.
Figure 2.
Concentrations of soluble carbohydrate and starch in grains on superior spikelets (SS) and inferior spikelets (IS) in rice of rice.
A: Dynamic change of soluble carbohydrate concentration in grains on SS and IS. B: Dynamic change of starch concentration in grains on SS and IS. C: Difference of soluble carbohydrate concentration between SS and IS at three stages. D: Difference of starch concentration between SS and IS at three stages. Experiments were repeated 6 times. Error bars represent standard errors. EGS, MGS and LGS represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS. Asterisk (*) represents significant difference (P = 0.05) between SS and IS.
Figure 3.
Representative 2-DE gels of proteins from superior spikelets (SS) and inferior spikelets (IS) at three grain-filling stages.
Three independent replicates for superior and inferior spikelets at each stage. EGS, MGS and LGS represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS. Proteins prepared from SS and IS at the EGS, MGS and LGS were separated by 2-DE and stained by Coomassie Brilliant Blue. The differentially expressed protein spots between SS and IS at three stages were determined according to the method described in “Materials and methods”. MW (in kilodaltons) and pI of the proteins are shown at left and top, respectively.
Figure 4.
Representative 2-DE gels of phosphoproteins from superior spikelets (SS) and inferior spikelets (IS) at three grain-filling stages.
Three independent replicates for SS and IS at each stage. EGS, MGS and LGS represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS. Proteins prepared from the EGS, MGS and LGS were separated by 2-DE and stained by Pro-Q Diamond phosphoprotein. The differentially expressed phosphoprotein spots between SS and IS at three stages were determined according to the method described in “Materials and methods”. MW (in kilodaltons) and pI of the proteins are shown at left and top, respectively.
Figure 5.
Patterns of change on differentially expressed protein spots (A) and phosphoprotein spots (B) of inferior spikelets (IS) in comparison to superior spikelets (SS).
EGS, MGS and LGS represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS.
Figure 6.
Differentially expressed protein and phosphoprotein for superior and inferior spikelets.
A: Code numbers of proteins at three stages. B: Code numbers of phosphoproteins at three stages. C: Comparative proteins and phosphopoteins.
Table 1.
List of protein spots with differential expressions between superior and inferior spikelets in 3 grain-filling stages.
Table 2.
List of phosphoprotein spots with differential expressions between superior and inferior spikelets in 3 grain-filling stages.
Figure 7.
Function classifications of identified proteins (A) and phosphoproteins (B).
Figure 8.
Function classifications of identified metabolism-related proteins (A) and phosphoproteins (B).
Figure 9.
Western blotting for comparing 14-3-3 protein and ADPase expressions of superior spikelets (SS) and inferior spikelets (IS) at three grain-filling stages.
Gels were divided into two parts at a molecular mass of approximately 66-3-3 protein and ADPase. EGS, MGS and LGS represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS.
Figure 10.
Difference on starch biosynthesis pathways between superior spikelets (SS) and inferior spikelets (IS).
Model of starch biosynthetic pathway according to Reference [28]. Blue pane represents differentially expressed proteins, red pane differed phosphorylation, and purple pane either differentially expressed proteins or differed phosphorylation. E, M and L represent early, mid-, and late grain-filling stage, respectively, of endosperm development stages of SS and IS. Black arrow represents proteins downregulated or upregulated in IS as compared to SS. Red arrow represents phosphoproteins downregulated or upregulated in IS as compared to SS. PGM: Phosphoglucomutase; UGPase: UDP-glucose pyrophosphorylase; AGPase: ADPglucose pyrophosphorylase; ADPGT: ADPglucose transporter; AATP: plastidic ATP transporter; GTP: Glucose-6-Phosphate transporter; GBSS: Granule bound starch synthase; Pul: Pullulanase; PPDK: Pyruvate, orthophosphate dikinas.