Stable plastid transformation in kiwifruit (Actinidia chinensis)

Plastid transformation offers valuable benefits in plant biotechnology, such as high-level transgene expression and the absence of gene silencing. Here we describe the first protocol of a plastid transformation system for a woody vine (liana) kiwifruit (Actinidia chinensis). The transgenic DNA carries a spectinomycin-resistance gene (aadA) cassette and a green fluorescent protein (GFP) reporter gene cassette, flanked by two adjacent kiwifruit plastid genome sequences, thereby allowing targeted insertion between the trnfM and trnG genes. Six spectinomycin-resistant shoots were obtained out of 12 plates subjected to bombardment, and two were positive events, confirmed through PCR and Southern blot analyses. The GFP was localized to plastids as monitored by confocal laser scanning microscopy and reached 2.5% of leaf total soluble protein. Success in kiwifruit extends transplastomic technology of woody species beyond poplar, and will provide an attractive biosynthetic chassis for molecular farming.

The online version contains supplementary material available at 10.1007/s42994-024-00186-0.