OsPK1

OsPK1(Cytosolic pyruvate kinase) catalyzes the last step of glycolysis. A dwarf rice mutant ospk1 shows the dwarf, panicle enclosure, reduction of setting rate, outgrowth of the Internodes lateral bud. T-DNA, one single copy of ospk1, inserts in the transcription regulation domain OsPK1, causing the wildtype expression reducing by 90％.OsPK1 encodes one cytoplasm PK. The complementation test shows the mutation of OsPK1is the main cause of the mutants configuration. OsPK1is main in the mesophyll cell, Stem with cell and the expression of Cortex parenchyma cell in root. In the mutant , pyruvic acid decreases. In addition, another four enzymes that involves in the gluconeogenic pathway, the expression of encoded genes changes. Thus ,OsPK1 plays an important role through affecting the gluconeogenic pathway. In the flag leaf and spike of the ospk1 mutant, the accumulation of glucose and fructose is increasing significantly, however the sucrose level in spike reduces by 84％. This results shows that due to the decline of OsPK1 expression, monosaccharide metabolism and sugar transportation have all change. In general, PKc plays a role in plant morphology especially in plant height.