MOLECULAR BASIS OF THE DWARFISM CHARACTER IN CULTIVATED PLANTS. I. GROWTH DISTORTIONS DUE TO MUTATIONS OF GIBBERELLIN METABOLISM AND SIGNALING (150,00 руб.)

The creation of novel high-yielding cultivars was one of the main purposes of the «Green revolution» aimed at the reorganization of agriculture in developing countries (G.S. Khush, 2001). <...> In connection with that the factors that predetermine plant growth have become of increasing scientific interest over recent years. <...> Numerous dwarf cultivars produced during the «Green revolution» possessed mutant genes responsible for metabolism and transmission of gibberellic (GA) signal (M. Ueguchi-Tanaka et al., 2001; T. Sakamoto et al., 2004). <...> GAs are involved in control of many stages of plant development, including seed germination, stem and root elongation (E. Tanimoto, 2012; P. Hedden, V. Sponsel, 2015). <...> However, alternations at different steps of the GA-dependent processes might lead to different results: to plants with reduced height as well as to tall slender plants. <...> The paper considers the ways of gibberellins biosynthesis, deactivation and how pool of active GAs is maintained. <...> GA20-oxidases and C3,β-oxidases (or C3,β-hydroxylases) involved in production of the active gibberellins catalyze final reactions of gibberellin biosynthesis. <...> C2,β-oxidases are main enzymes that can quickly inactivate active GAs by adding a hydroxyl group (–OH) to a GA molecule. <...> Modern concept about GAsignaling is reviewed according to the following established steps: GA receptor GID1; DELLAproteins as the negative regulators in GA signaling; SCF E3-ubiqutin protein ligase and 26S proteasome; transcriptional factors with DNA-binding site; GA-regulated genes. <...> Accumulated up-to-date data consider that in transmission of gibberellic signal a GA molecule initiates DELLA-protein degradation via interaction of GID1-DELLA complex with E3 SCFSLY1/GID2 (T.-P. Sun, 2011). <...> Thus, reduced growth in dwarf cultivars can be associated with defects in biosynthesis of the active GAs or with accumulation of repressors of GA signaling, the DELLA-proteins, while GA-constitutive growth in tall slender forms might be caused by disturbance in GA-deactivation system or lack of the DELLA repressive function (H. Claeys et al., 2014). <...> The paper also considers ways of participation of gibberellin in the complex hormone regulation of plant growth which occurs often via control over the repressive function of DELLA-proteins (P. Achard et al., 2003). <...> Among plant dwarf <...>