Fructan determination in transgenic nicotiana tabacum l. Plants harbouring human inf α2b gene infected by tobacco mosaic virus

Abstract

Fructan is one of the main storage compounds in higher plants, their accumulation and synthesis is associated with the plant's adaptation. They take part in cryoprotection, osmoregulation and water balance and included in plant protection from pathogens (biotic stress). Fructan, anthocyanins, proline are involved in reduction of negative effects of biotic factors on plants. Utilizing of genetic engineering methods makes it possible to create stress resistant plants. However, the impact of the transformation still remains unclear, because transformation can be regarded as biotic stress factor for plants. Investigation of the biotic stress effects on metabolic pathways in transformed plants is still actual. The aim of our work was to identify changes in fructan accumulation caused by the presence of tobacco mosaic virus (TMV) in transgenic Nicotiana tabacum plants with human ifn-α2b gene. Control wild type plants contained 6.8 + 0.08 mg/g of fructan. In the transgenic line №1, the level of fructan accumulation was 4.68 ± 1.02 mg/g. In the transformed line №3, its content increased to 30+1.8 mg/g. The fructan content in control plants increased from 6.8 + 0.08 to 8.2 + 1 mg/g, after viral infection. For transgenic line №1, the content of fructan increased to 25 + 1 mg/g. The growth of fructan concentration was not observed in the line №3. The increase in fructan content in infected transgenic plants can be regarded as adaptive response to viral infection as biotic stress.