| 摘要 |
The present invention provides methods for the high-level production of recombinant human erythropoietin (rhuEPO) derivative, asialoerythropoietin (asialo-rhuEPO), in plants. The methods for producing asialo-rhuEPO comprise making a plant or at least one plant cell that comprises a promoter that drives expression in a plant cell operably linked to a polynucleotide encoding a human erythropoieting fusion protein and a promoter that drives expression in a plant cell operably linked to a polynucleotide encoding N-glycosylation modification enzyme, particularly a mammalian β1,4-galactosyltransferase. The present invention further provides plants, plant cells, and seeds that have been genetically modified to produce high levels of asialo-rhuEPO. Additionally, provided are methods for purifying asialo-rhuEPO from plant tissues. Such methods comprise removing chlorophyll and/or RuBisCO protein from an aqueous extract of plant tissue comprising asialo-rhuEPO, binding the asialo-rhuEPO in the extract to an immune affinity column, and eluting the bound asialo-rhuEPO from immune affinity column. |
