Biomics

Plant α-expansin genes are of great interest for genetic engineering, since they can be used to improve the growth of the roots of agricultural plants. Previously, we obtained transgenic tobacco plants Nicotiana tabacum overexpressing the PnEXPA3 expansin gene from black poplar Populus nigra. In this work, the growth of roots of transgenic plants was studied under normal conditions and under the influence of stress factors such as hypothermia, salinity and heavy metals. Constitutive expression of the PnEXPA3 gene improved the growth of roots of transgenic tobacco plants as compared to the wild type under normal conditions and under hypothermia (+10°C), salinity (50 and 100 mM NaCl) and the action of heavy metals (200 and 400 μM acetate cadmium). The totality of the obtained data suggests that the constitutive expression of the PnEXPA3 gene can be used to improve the growth of roots of cultivated plants both under normal conditions and the action of stress factors.

constitutive expression, transgenic plants, Nicotiana tabacum, root growth, heavy metals, salt stress, hypothermia

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