Analysis of differentially expressed genes under UV-B radiation in the desert plant Reaumuria soongorica.

PMID 26277248


Reaumuria soongorica is one of the typical desert plants that present excellent tolerance to adverse environments. However, its molecular response to UV-B radiation remains poorly understood. To test the response and tolerance mechanisms of R. soongorica to the increasing UV-B radiation, the differentially expressed genes (DEGs) were investigated between the control and UV-B radiation groups. A total of 2150 DEGs were detected between the two groups, of which 561 were up-regulated and 1589 were down-regulated. For functional analysis, DEGs were divided into three groups: (i) Chloroplast-localized proteins, including photosynthesis-associated proteins, ribulose-phosphate-3-epimerase, and ATP-dependent Clp protease. Their transcripts were inhibited, implying that the normal function of chloroplast was affected by UV-B radiation. (ii) Proteins involved in signaling transduction, such as phototropins and GTP-binding proteins. The transcriptional alternation of phototropins may reduce the penetration of UV-B radiation by regulating phototropism, stomatal opening, and chloroplast relocation. The down regulation of GTP-binding proteins may inhibit replication of potentially damaged DNA through preventing cell division; and (iii) proteins for lipid transfer and flavonoids biosynthesis. The up-regulation of these genes suggested that lipid transfer and flavonoids may have a protective function in response to UV-B radiation. Thus, UV-B radiation may lead to the disruption of chloroplasts function. The induction of genes for signal transduction and protective proteins may be a strategy for responding to UV-B radiation in R. soongorica.