Agrology (Nov 2022)
Features of polypeptide composition of seed reserve proteins in species of the genus Tilia under conditions of urban agglomeration
Abstract
Plants of the genus Tilia L. are one of the most widespread decorative species in Ukraine. Anthropogenic environmental factors negatively affect the tree growth and development (including seed viability), which negatively affects plant ontogenesis. Studying the variability of seed proteins is an effective method for detecting the effects of various types of pollutants on plants. Despite the importance of seed proteins, their polypeptide composition in different species of the genus Tilia is yet little known in the conditions of the northern steppe of Ukraine. To assess the functional adaptive responses of trees of various Tilia species to the complex influences of anthropogenic and natural factors of the steppe Dnipro region, the parameters of polypeptide composition of highly soluble proteins (HSP) in the endosperm were determined in seeds of autochthonous (T. cordata) and introduced (T. platyphyllos, T. begoniifolia, T. × europaea, T. amurensis and T. tomentosa) species. Linden tree seeds were selected in the Dnipropetrovsk Region in 14 sample plots, chosen according to the level of urban and technogenic loads. The spectra of protein polymorphism in linden seeds were studied by the method of gradient electrophoresis in polyacrylamide gel (linear gradient within the range of 10–20%) in the presence of 0.1% sodium dodecyl sulfate. Polypeptides from seeds were extracted with 0.005 M tris-glycine buffer, pH 8.0. We used a vertical electrophoresis in our study. The separated proteins were stained with a 0.1% Coomasie G-250 dye solution in 7% acetic acid. Egg albumin (Mr 45 kDa), cytochrome C (12 kDa), bovine serum albumin (67 kDa), and chymotrypsin (30 kDa) were used as standards for developing a calibration curve for determining the molecular weight of polypeptides. In the seeds of plants of the genus Tilia, changes in the composition and accumulation of individual polypeptides in the protein complex were evaluated. The appearance of polypeptides with new molecular weight values was deermined in comparison with the reference. Tilia cordata and T. platyphyllos were characterized by the appearance of low-molecular polypeptides (19, 26, 27 and 28 kDa), which in most cases appeared due to the effects of emissions from metallurgical industries, thermal power plants, nitrogen production, and in park areas (in seeds of T. platyphyllos). In seeds of T. begoniifolia and T. amurensis, the appearance of polypeptides with average molecular weights of 39, 52, 45 and 53 kDa was detected.
