Molecular analysis of the genes in and their responses to heat stress.

BACKGROUND

is a perennial and semi-shady herb with tremendous medicinal value. Due to its unique botanical characteristics, ginseng is vulnerable to various abiotic factors during its growth and development, especially in high temperatures. Proteins encoded by genes form a highly conserved protein family that widely exists in eukaryotes. The family regulates the vital movement of cells and plays an essential role in the response of plants to abiotic stresses, including high temperatures. Currently, there is no relevant research on the genes of ginseng.

METHODS

The identification of the ginseng gene family was mainly based on ginseng genomic data and Hidden Markov Models (HMM). We used bioinformatics-related databases and tools to analyze the gene structure, physicochemical properties, -acting elements, gene ontology (GO), phylogenetic tree, interacting proteins, and transcription factor regulatory networks. We analyzed the transcriptome data of different ginseng tissues to clarify the expression pattern of the gene family in ginseng. The expression level and modes of genes under heat stress were analyzed by quantitative real-time PCR (qRT-PCR) technology to determine the genes in the gene family responding to high-temperature stress.

RESULTS

In this study, 42 genes were identified from the ginseng genome and renamed to . Gene structure and evolutionary relationship research divided into epsilon (ε) and non-epsilon (non-ε) groups, mainly located in four evolutionary branches. The gene structure and motif remained highly consistent within a subgroup. The physicochemical properties and structure of the predicted proteins conformed to the essential characteristics of proteins. RNA-seq results indicated that the detected existed in different organs and tissues but differed in abundance; their expression was higher in roots, stems, leaves, and fruits but lower in seeds. The analysis of GO, -acting elements, interacting proteins, and regulatory networks of transcription factors indicated that might participate in physiological processes, such as response to stress, signal transduction, material synthesis-metabolism, and cell development. The qRT-PCR results indicated had multiple expression patterns under high-temperature stress with different change trends in several treatment times, and 38 of them had an apparent response to high-temperature stress. Furthermore, was significantly upregulated, and was significantly downregulated in all treatment times. This research lays a foundation for further study on the function of genes and provides theoretical guidance for investigating abiotic stresses in ginseng.