Genome-Wide Identification and Expression Analysis of Gene Family in Response to Multiple Stresses in Ramie ( L.).

The protein phosphatase 2C (), a key regulator of the ABA signaling pathway, plays important roles in plant growth and development, hormone signaling, and abiotic stress response. Although the gene family has been identified in many species, systematic analysis was still relatively lacking in ramie ( L.). In the present study, we identified 63 genes from the ramie genome, using bioinformatics analysis, and classified them into 12 subfamilies, and this classification was consistently supported by their gene structures and conserved motifs. In addition, we observed that the functional differentiation of the family of genes was restricted and that fragment replication played a major role in the amplification of the gene family. The promoter -regulatory elements of genes were mainly involved in light response regulation, phytohormone synthesis, transport and signaling, environmental stress response and plant growth and development regulation. We identified genes with tissue specificity, using ramie transcriptome data from different tissues, in rhizome leaves and bast fibers. The qRT-PCR results showed that the , and genes had a strong response to drought, high salt and ABA, and there were a large number of stress-responsive elements in the promoter region of and . The results suggested that and could be used as the candidate genes for drought and salt tolerance in ramie. These results provide a reference for further studies on the function of the gene and advance the development of the mechanism of ramie stress response, with a view to providing candidate genes for the molecular breeding of ramie for drought and salt tolerance.