LAUSR

Angiogenesis plays an important role in tumor growth and metastasis of cancer. Vascular endothelial growth factor is the key regulator in stimulating angiogenesis. The VEGF activity is mediated by binding to its cell-surface receptors, mainly VEGFR2. Therefore, inhibition of the VEGF/VEGFR2 interaction by antibodies is investigated as a therapeutic strategy in cancer therapy. Here, we describe transient expression of an anti-VEGFR2 nanobody (3VGR19) by a viral vector based on Turnip mosaic virus in lettuce (Lactuca sativa L.). RT-PCR analysis demonstrated the 3VGR19 transcript expression. Western blot analysis showed the 3VGR19 protein expression with an expected molecular mass of ~15 kDa and based on the ELISA results, the expression level of 3VGR19 was 8 μg/g of leaf fresh weight. Taken together, recombinant 3VGR19 could be efficiently expressed in lettuce leaves and TuMV-based expression system would be an appropriate platform for production of recombinant proteins in lettuce plants.