THE ROLE OF MICRORNAS IN THE DEVELOPMENT OF PLANT RESISTANCE TO COLD

Plants, as sessile organisms, are forced to adapt to changes in the environment, including temperature changes that limit growth, development and productivity). Abiotic stresses have become a serious problem due to their widespread nature and destructive effects on plants. However, plants have developed complex ways to perceive and respond to environmental changes. The mechanisms of plant resistance to hypothermia have been studied for a long time and transcriptional control of expression of genes sensitive to cold has been studied in some detail. To activate protective mechanisms, plants trigger a network of genetic regulators, including changing the expression of a significant part of genes using transcriptional and/or translational regulators. microRNAs can be considered important participants in the response of plants to cold stress. The key to understanding the involvement of microRNAs in plant stress reactions was studies that showed the regulation of their expression under stress. microRNAs are small non-coding RNAs that manifest themselves as important regulatory components in plants. microRNA expression includes transcription of microRNA genes by RNA polymerase II, multistage processing of primary transcripts using the enzyme DICER-LIKE1 (DCL1) and the formation of an effector complex consisting of miRNAs and proteins of the ARGONAUTE (AGO) family. Such complexes interact with complementary RNA targets, suppressing their expression at the transcriptional and post-transcriptional levels. Thus, microRNAs regulate a variety of biological processes, including responses to changes in the environment. Currently, microRNAs are considered as an important tool for regulating the work of genes. Such significant processes in plants as maintaining homeostasis, growth and development, transition from the vegetative to the reproductive phase, signaling and response to various stresses are regulated by microRNAs. The article describes the role of microRNAs in the response of plants to cold stress, analyzes microRNA targets, and discusses the prospects for using microRNAs in the practice of improving plant resistance to external influences.