Microtuber slices of potato cultivar ‘‘Atlantic’’ were co-
cultured (media: MS + 1 mg/L, IAA + 0.2 mg/L, GA3 + 0.5 mg/
L, 6-BA + 2 mg/L ZT) for two days with A. tumefaciens
LBA4404 containing the plasmid pBI121-CaMV 35S-CryIIIA
and pBI121-ST-LS1-CryIIIA respectively, then transferred
into the selected medium supplemented with 50 mg/L of
kanamycin. After three weeks, green buds sprouted directly
from the surface of the slices (Fig. 1A). When the green
X. Mi et al. / C. R. Biologies 338 (2015) 443–450 445
shoots reached a length of 1 cm, they were transferred to a
selective rooting medium containing 100 mg/L of kanamy-
cin. Roots were formed in about 10 days (Fig. 1B). Plantlets
with well-developed roots were propagated for further
molecular analysis. Genomic DNA indicating the presence of
the cry3A gene in the putative transformed plants was
extracted and confirmed by PCR assay. The result showed
that the transformed plants had a 709-bp amplification
product, which was missed in control plants (Fig. 2). qRT-
PCR analysis showed that cry3A gene expressed in roots,
stems and leaves, except the roots contained the ST-LS1
promoter and the whole tissue in the control plants, and had
higher expression in leaves than in stems and roots (Fig. 3).