Gene expression
Expression of chlorophyll biosynthesis genes: To understand the reasons for increased Chl biosynthesis (see above) inFbβCA overexpressor plants, the expression of a few selected genes involved in Chl biosynthesis pathway was monitored. In comparison with the VC, the message abundance of PBGS(porphobilinogen synthase), involved in the synthesis of the pyrrole ring porphobilinogen, was found to be 1.7 and 2.2 fold higher in CAx3 and CAx5, respectively, than in the VC (Fig. 5a ). The transcript expression of UROD (uroporphyrinogen decarboxylase), responsible for the synthesis of coproporphyrinogen, was 2.0 and 2.2 fold higher in CAx3 and CAx5 as compared to VC (Fig. 5a) . The gene expression of PPOX (protoporphyrinogen oxidase), responsible for protoporphyrin IX synthesis, increased 1.4-3 fold in the transgenics (Fig. 5a ). The message abundance of CHLI(protoporphyrin-IX Mg-chelatase), one of the 3 genes responsible for Mg insertion to protoporphyrin IX moiety, increased by 1.4 and 1.5 fold in CAx3 and CAx5, respectively, than in the VC (Fig. 5a ). The expression of light-inducible PORC (protochlorophyllide oxidoreductase) was 1.8-2.5 fold higher in transgenics than in the VC plants (Fig 5a) .
Expression of photosynthesis-related genes : The gene expression of Lhcb1 and Lhcb2.1encoding components, of the light harvesting complex associated with PSII, was 2.1-2.5 and 1.9-2.5 fold higher in the transgenics(Fig 5b) . The gene expression of Lhca1 and Lhca2(encoding components of the light harvesting complex associated with PSI) increased by 2- 3.45 and 1.2 –1.4 fold in the overexpressors(Fig. 5b) . Expression of two core proteins PsbA, and, PsbD, encoding photosystem II D1 and D2 proteins, was 3.2-3.6 and 1.7-2.3 fold higher in the transgenics (Fig. 5b) . PsbO (encoding for OEC33, the oxygen-evolving complex) increased, as compared to that in the VC plants, by 1.4 and 2.4 fold in CAx3 and CAx5 as compared to VC