Transgenic maize phosphoenolpyruvate carboxylase alters leaf-atmosphere CO₂ and ¹³CO₂ exchanges in Oryza sativa.

ABSTRACT: The engineering process of C₄ photosynthesis into C₃ plants requires an increased activity of phosphoenolpyruvate carboxylase (PEPC) in the cytosol of leaf mesophyll cells. The literature varies on the physiological effect of transgenic maize (Zea mays) PEPC (ZmPEPC) leaf expression in Oryza sativa (rice). Therefore, to address this issue, leaf-atmosphere CO₂ and ¹³CO₂ exchanges were measured, both in the light (at atmospheric O₂ partial pressure of 1.84 kPa and at different CO₂ levels) and in the dark, in transgenic rice expressing ZmPEPC and wild-type (WT) plants. The in vitro PEPC activity was 25 times higher in the PEPC overexpressing (PEPC-OE) plants (~20% of maize) compared to the negligible activity in WT.

SUBMITTER: Giuliani R 

PROVIDER: S-EPMC6848035 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature