Expression of human interferon gamma in <i>Brassica napus</i> seeds

Abstract

Expressions of heterologous proteins in suitable plant tissues and targeting it into subcellular compartments using specific signals have been studied. Seed-based platforms are among those that allow recombinant proteins to stably accumulate at a relatively high concentration in a compact biomass. In this study, we used seed specific promoter (Napin) and C-terminal KDEL sequence to express human therapeutic protein, interferon gamma (IFN_y) in Brassica napus seeds. Kozak sequence was linked to the 5' end of the IFN_y gene to increase the level of expression. The constructed cassette was transformed into rapeseed. Presence and expression of the transgene were confirmed in the transformants by polymerase chain reaction (PCR) and sodium dodecylsulfatepolyacrylamide gel electrophoresis (SDS-PAGE). Analysis of transgenic plants by enzyme-linked immunosorbent assay (ELISA), dot blot and western blot indicated that IFN_y protein is being expressed in B. napus seeds and is as active as the standard IFN_y. Our results indicate that plant seeds have tremendous potential for production of recombinant proteins as ‘natural bioreactors’.

Key words: Interferon gamma, KDEL retention signal, seed specific promoter, Brassica napus, recombinant proteins.