**1. Introduction**

The genomic information in plants, similar to other eukaryotes, is implemented via a successive series of biological processes, including transcription and translation as the key events. The current experimental omics tools for genomic monitoring of plant gene expression allow tracking the flow of genetic information from genome to proteome and to metabolome. New experimental approaches, for example, RNA-Seq and DNA microarrays, have given insight into many key mechanisms involved in transcription regulation in plants: the first stage of gene expression and the easiest to study in terms of experimental methodology. The studies of transcriptomes, i.e., the qualitative and quantitative estimation of expression of the entire gene pool on a genome-wide scale, have given convincing evidence of dynamic changes in the transcriptomes of various plant species in both growth and

development processes and the impact of environmental factors. Comparative omics studies in plants clearly demonstrate a very modest correlation between the levels of transcription (abundance of individual mRNAs) and translation (the levels of the corresponding proteins in the proteome). Of note, the observed fluctuations in the levels of a transcript do not always lead to changes in the levels of the corresponding protein [1]. This suggests an intricate nature of the mechanisms providing the decoding of a genome, which involve not only differential transcription, but also differential translation.

Translation is a complex biological process with numerous players, including mRNAs, tRNAs, ribosomes, and manifold protein factors. Undoubtedly, each is important for efficient translation. The mRNAs themselves comprise different regions, namely, the 5' untranslated region (5'UTR) and coding region (CDS) and 3' untranslated region (3'UTR), which modulate translation at a number of "checkpoints": translation initiation, elongation, and termination. In the current view, numerous regulatory elements may be concealed in the nucleotide contexts of these mRNA regions and each of them individually or in combination can determine the development of any transcript in translational process [2].

The paradox of misfit between the levels of mRNAs and their protein products observable in different plant species at all stages of their growth and development as well as upon the impact of various environmental factors focuses the attention of researchers on two key problems, namely (i) detection of the specific sets of differentially-translated transcripts, i.e., the sets of transcripts that are efficiently translated under certain conditions, and the sets of transcripts with repressed or unchanged translation under the same conditions and (ii) clarification of the particular regions or specific structural features of the mRNA nucleotide composition that mediate this differential translational control.

This review focuses on the experimental methods for genome-wide analysis of translational control, computational algorithms to search and analyze various regulatory contexts within mRNAs, and approaches for subsequent experimental verification of their correlation with mRNA translation in plants. Currently, we cannot refer to deficiency in publications comprehensively reporting the basic protocols of various methods for genome-wide analyses of translational control in general, including the methods applicable to plant objects. However, reviews that consider and discuss the three key components of the general strategy for identification of regulatory contexts in mRNA that may play a key role in differential translation are still absent in the scientific literature. Our goals here are (i) to consider the experimental approaches aiming to clarify differential translation on a plant genome-wide scale; (ii) to summarize the current data on the computational algorithms used for detection of the specific structural and functional features of key determinants within plant mRNAs and their interrelation with the translation efficiency; (iii) to highlight the methods for experimental verification of existed data and theoretical predictions of the intrinsic features of plant mRNAs important for their differential translation; and (iv) to discuss the ways of decoding the specific structural features of plant mRNA that mediate differential translational control by combining computational and experimental approaches. In general, this review discusses the main and critical steps for each method in this general strategy, areas of their application, and the main results obtained using plant objects and their contribution to our knowledge about the fine mechanisms of translation in plants.
