Morphophysiological alterations in transgenic rice lines expressing PPDK and ME genes from the C4 model Setaria italica

被引：15

作者：

Swain, Alaka ^{[1
]}

Behera, Deeptirekha ^{[1
]}

Karmakar, Subhasis ^{[1
]}

Dash, Manaswini ^{[1
]}

Dash, Bisnu Prasad ^{[2
]}

Swain, Padmini ^{[1
]}

Molla, Kutubuddin A. ^{[1
]}

Baig, Mirza J. ^{[1
]}

机构：

[1] ICAR Natl Rice Res Inst, Cuttack 753006, Odisha, India

[2] Fakir Mohan Univ, Dept Biosci & Biotechnol, Balasore 756020, Odisha, India

来源：

JOURNAL OF PLANT PHYSIOLOGY | 2021年 / 264卷

关键词：

Pyruvate orthophosphate dikinase; Malic enzyme; Photosynthetic rate; Chlorophyll fluorescence; Electron transport rate; Stomatal conductance; Nonphotochemical quenching; NADP-MALIC ENZYME; C-4 PHOTOSYNTHETIC PATHWAY; HIGH-LEVEL EXPRESSION; PHOSPHOENOLPYRUVATE CARBOXYLASE; ORTHOPHOSPHATE DIKINASE; CHLOROPHYLL FLUORESCENCE; OVER-EXPRESSION; CONFERS SALT; PLANTS; MAIZE;

D O I：

10.1016/j.jplph.2021.153482

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

C4 plants are superior to C3 plants in terms of productivity and limited photorespiration. PPDK (pyruvate orthophosphate dikinase) and NADP-ME (NADP-dependent malic enzyme) are two important photosynthetic C4 specific enzymes present in the mesophyll cells of C4 plants. To evaluate the effect of C4 enzymes in rice, we developed transgenic rice lines by separately introducing Setaria italica PPDK [SiPPDK] and S. italica ME [SiME] gene constructs under the control of the green tissue-specific maize PPDK promoter. Rice plant lines for both constructs were screened using the polymerase chain reaction (PCR), Southern hybridization, and expression analysis. The best transgenic plant lines for each case were selected for physiological and biochemical characterization. The results from qRT-PCR and enzyme activity analysis revealed higher expression and activity of both PPDK and NADP-ME genes compared with the nontransformed and empty-vector-transformed plants. The average photosynthetic efficiency of transgenic plant lines carrying the PPDK and NADP-ME genes increased by 18% and 12%, respectively, and was positively correlated with the increased accumulation of photosynthetic pigment. The decrease in Fv/Fm, increased electron transport rate (ETR), and increased photochemical quenching (qP) compared with nontransformed control plants suggest that transgenic rice plants transferred more absorbed light energy to photochemical reactions than wild-type plants. SiME-transgenic plants displayed reduced leaf malate content and superior performance under water deficit conditions. Interestingly, the trans genic plants showed yield enhancement by exhibiting increased plant height, panicle length, panicle weight and thousand grain weight. Overall, the exogenous foxtail millet C4 gene PPDK enhanced photosynthesis and yield to a greater extent than NADP-ME.

引用

页数：13