Over-expression of a novel Arabidopsis phosphatase causes accelerated flowering and higher photosynthesis rate in Camelina Stavia

Abstract

Camelina Stavia, which needs little water or nitrogen to flourish, can be grown on marginal agricultural lands and used as a source of low-input biofuel. Currently, the low yield of the Camelina seed limits its commercial value and large-scale production despite its adaptation to a wide range of climates. A novel phosphatase from Arabidopsis was introduced to Camelina by Agrobacterium-mediated transformation and was overexpressed by a CaMV35S promoter. Transgenic Camelina plants expressing Arabidopsis phosphatase showed enhanced photosynthetic efficiency and growth characteristics under growth chamber conditions at 16 h light/8 h dark cycle. Three homologous over-expression lines (OE) were selected and confirmed by western blotting. The OE Lines flowered at Day 43 + /-2, whereas the wild-type and null lines flowered at Day 53 +/- 2. Compared to the wild-type and the null lines, photosynthetic CO2 fixation in the transgenic plants were increased 10-20% at the light intensity of 400 μmol/M-2/S-1 and 20-40% at the light intensity of 1000 μmol/M-2/S-1. Transgenic Camelina also showed increase in stomatal conductance from about 30% to about 50% in different light intensity from 400 μmol/M-2/S-1 to 1000 μmol/M-2/S-1compared with the wild-type and null lines plants. Fourier Transformation Mass Spectrum (FT-MS) measurement of sugars in rosette leaves of 35-day-old plants are being carried out to examine the change of the metabolites in transgenic plant.