Expression of plastid genome and development of Arabidopsis thaliana with disturbed synthesis of brassinosteroids

Abstract

Comparative analysis of growth characteristics, content of auxins and cytokinins, and the level of photosynthetic pigments was conducted in det2 mutant plants of Arabidopsis thaliana (L.) Heynh notable for a disturbed synthesis of brassinosteroids and therefore their low endogenous level. In this mutant line, we observed de etiolation: the formation of large cotyledons and long hypocotyls in the dark already shown ear lier. For the first time, we analyzed transcription of 12 chloroplast genes encoding functionally different pro teins and RNAs in rosette leaves of wild type and det2 plants. In rosette leaves of mutant plants, transcription activity of the investigated plastid genes was much higher than in the parental line. On these grounds, we assumed that the low level of brassinosteroids was correlated with the activation of transcription of some chlo roplastic genes and realization of the de etiolation program.

Effect of exogenously applied 20-hydroxyecdysone on the efficiency of primary photosynthetic processes substantially differs across plant species

“…BRs have been proposed to act as more immediate regulators of the PETC and available evidence suggests that this could be indeed true. Studies show that various genes coding for components of the PETC belong to the group that is regulated at least on the transcriptional level by BRs (Komatsu et al 2010, Sun et al 2010, Efimova et al 2012a. BRs also participate in the regulation of the organization of the chloroplast thylakoid membrane system, which is the place where the PETC occurs (Krumova et al 2013, Dobrikova et al 2014, Schröder et al 2014, Liu et al 2016.…”