Biologia Plantarum (Sep 2019)
Identification of differentially expressed genes of Haloxylon ammodendronin response to salinity stress
Abstract
Haloxylon ammodendron (C.A. Mey.), an endangered desert tree with excellent drought and salinity tolerance, provides a unique genotype to characterize and understand the tolerance mechanisms. In this study, four RNA-Seq libraries were constructed and sequenced from H. ammodendron under salinity stress. Total 12 027 differentially expressed genes (DEGs) were identified, in which 4 023, 3 517, 4 487 genes were differentially expressed under light salinity stress (200 mM NaCl), moderate salinity stress (400 mM NaCl), and severe salinity stress (800 mM NaCl), respectively. The up-regulated DEGs included several transcription factors (e.g., MYB and bHLH), hormone-related genes (e.g., cytochrome P450), protein kinases (e.g., Atpk2-Atpk19 like), and genes involved in carbon metabolism (e.g., UDP glycosyltransferase), osmotic regulation (e.g., proline transporter), and ubiquitin proteasome system (e.g., ubiquitin-conjugating enzymes). Heat shock proteins were identified as positive regulators of salinity tolerance in H. ammodendron. The expression patterns of 13 DEGs verified by real-time quantitative PCR were identically consistent with the variations in transcript abundance identified by RNA-Seq. Our results provide new insights into molecular mechanism of H. ammodendron in response to salinity stress.
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