Nanobody Mediated Atrazine Resistance in Plants

In planta expression of recombinant antibodies has been proposed as a strategy for herbicide resistance but is not well advanced yet. Here, an atrazine nanobody gene fused with a green fluorescent protein tag was transformed to Arabidopsis thaliana, which was confirmed with PCR, ELISA, and immunoblotting. High levels of nanobody accumulation were observed in the nucleus, cytoderm, and cytosol. The nanobody expressed in the plant had similar affinity, sensitivity, and selectivity as that expressed in Escherichia coli. The T3 homozygous line showed resistance in a dose-dependent manner up to 380 g ai/ha of atrazine, which is approximately one-third of the recommended field application rate. This is the first report of utilizing a nanobody in plants against herbicides. The results suggest that utilizing a high-affinity herbicide nanobody gene rather than increasing the expression of nanobodies in plants may be a technically viable approach to acquire commercial herbicide-resistant crops and could be a useful tool to study plant physiology.