Transgenic Rice Expressing Ictb and FBP/Sbpase Derived from Cyanobacteria Exhibits Enhanced Photosynthesis and Mesophyll Conductance to CO2

PLoS One. 2015 Oct 21;10(10):e0140928. doi: 10.1371/journal.pone.0140928. eCollection 2015.

Abstract

To find a way to promote the rate of carbon flux and further improve the photosynthetic rate in rice, two CO2-transporting and fixing relevant genes, Ictb and FBP/Sbpase, which were derived from cyanobacteria with the 35SCaMV promotor in the respective constructs, were transformed into rice. Three homologous transgenic groups with Ictb, FBP/Sbpase and the two genes combined were constructed in parallel, and the functional effects of these two genes were investigated by physiological, biochemical and leaf anatomy analyses. The results indicated that the mesophyll conductance and net photosynthetic rate were higher at approximately 10.5-36.8% and 13.5-34.6%, respectively, in the three groups but without any changes in leaf anatomy structure compared with wild type. Other physiological and biochemical parameters increased with the same trend in the three groups, which showed that the effect of FBP/SBPase on improving photosynthetic capacity was better than that of ICTB and that there was an additive effect in ICTB+FBP/SBPase. ICTB localized in the cytoplasm, whereas FBP/SBPase was successfully transported to the chloroplast. The two genes might show a synergistic interaction to promote carbon flow and the assimilation rate as a whole. The multigene transformation engineering and its potential utility for improving the photosynthetic capacity and yield in rice were discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agrobacterium tumefaciens / genetics
  • Anion Transport Proteins / genetics*
  • Bacterial Proteins / genetics*
  • Biological Transport / genetics
  • Carbon Dioxide / metabolism
  • Cation Transport Proteins / genetics*
  • Chloroplasts / genetics
  • Chloroplasts / metabolism
  • Cyanobacteria / enzymology
  • Cyanobacteria / genetics*
  • Flowers / genetics
  • Fructose-Bisphosphatase / genetics*
  • Mesophyll Cells / metabolism
  • Oryza / anatomy & histology
  • Oryza / genetics*
  • Photosynthesis / genetics*
  • Plant Leaves / anatomy & histology
  • Plants, Genetically Modified / genetics

Substances

  • Anion Transport Proteins
  • Bacterial Proteins
  • Cation Transport Proteins
  • Carbon Dioxide
  • Fructose-Bisphosphatase

Grants and funding

http://www.nsfc.gov.cn/, National Natural Science Foundation of China. (31271699) Han Yu Gong; http://www.nsfc.gov.cn/, National Natural Science Foundation of China. (30971741) Yang Sheng Li. The National Program of Transgenic Variety Development of China (Grant No. 2011ZX08001-001 and 2011ZX08001-004); and Key Grant Project of Chinese Ministry of Education (Grant No. 313039). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.