关键词: 非编码RNA, 盐胁迫, 干旱胁迫, 小RNA测序, 降解组

Abstract:

China is a maritime power with a long coastline and abundant coastal resources. However, this long costline brings vast areas of saline-alkali land. Additionally, global warming has led to more frequent seasonal drought. Under such extreme conditions, the survival rate of most plants is very low. Therefore, research on the molecular mechanisms of drought resistance and salt tolerance is particularly important. Improving the survival rate of plants in arid and saline-alkali areas can bring significant ecological benefits and economic value. Non-coding RNA (ncRNA) is a class of genetic information molecules transcribed from the genome that do not encode proteins. As a major focus of epigenetic research, ncRNAs were once considered the “dark matter” or “transcriptional noise” of the genome. The most well-known type of ncRNA is microRNA (miRNA), a highly conserved class of short non-coding small RNA molecules that are 20-24 nucleotides in length. They regulate the growth and development of organisms by cleaving and degrading target gene transcripts or inhibiting the translation of target genes through complementary base pairing with target sites. With the development of miRNA research methods such as small RNA sequencing and degradome sequencing, an increasing number of miRNAs and their target genes has been reported in animals and plants. Their biological synthesis, processing, maturation, and functional effects have been elucidated. Plant miRNAs complementarily pair with their target genes mostly in the open reading frame, with a full or nearly full complementarity to the target sequences. These characteristics stimulated the rapid development in plant miRNA research, and a large amount of research has revealed important regulatory roles of miRNAs in plant growth, development, and stress responses. This article provides a systematic review of the features, synthesis process, mode of action, and research progress of plant miRNAs in drought and salt resistance. We summarizes the main techniques and strategies for plant miRNA research in recent years, discuss the existing problems and prospects, and reveals the regulatory mechanisms of miRNA in plant drought and salt resistance, providing a basis for generating new varieties of drought and salt resistance.

Key words: non-coding RNA, salt stress, drought stress, small RNA-Seq, degradome