The expression of cyanobacterial glycolate-decarboxylation pathway genes improves biomass accumulation in Arabidopsis thaliana

Abstract

Transgenic Arabidopsis thaliana plants expressing cyanobacterial decarboxylation genes GLCD1 (GLYCOLATE DEHYDROGENASE I), HDH (HYDROXYACID DEHYDROGENASE), ODC (OXALATE DECARBOXYLASE) alone, and HDH::ODC simultaneously were successfully developed. Plants independently expressing GLCD1, HDH, ODC, and HDH::ODC were referred to as GD, HD, OX, and HX plants, respectively. The single-copy homozygous GD, HD, OX, and HX plants exhibited appreciable expression of chimeric genes. Phenotypic characterization demonstrated that rosette diameter of GD, HD, OX, and HX was 20, 22, 17, and 16% higher than wild-type (WT) plants. Total numbers of leaves were 32, 35, 37, and 34% more than WT plants after 32 days of sowing. Similarly, all transgenic plants produced more cauline branches than WT plants. All transgenic plants gained more height as compared to WT when recorded after 42 days of growth except HX transgenic plants. Plants vegetative dry biomass was 43% (GD), 35% (HD), 42% (OX), and 36% (HX) higher than WT plants. This is the first report on characterization of cyanobacterial decarboxylation pathway genes, which will pave the way for transformation of complete pathway in plants for better biomass accumulation.