Characterization of the Transcriptome of the Xerophyte Ammopiptanthus mongolicus Leaves under Drought Stress by 454 Pyrosequencing

Abstract

Background Ammopiptanthus mongolicus (Maxim. Ex Kom.) Cheng f., an endangered ancient legume species, endemic to the Gobi desert in north-western China. As the only evergreen broadleaf shrub in this area, A. mongolicus plays an important role in the region’s ecological-environmental stability. Despite the strong potential of A. mongolicus in providing new insights on drought tolerance, sequence information on the species in public databases remains scarce. To both learn about the role of gene expression in drought stress tolerance in A. mongolicus and to expand genomic resources for the species, transcriptome sequencing of stress-treated A. mongolicus plants was performed.ResultsUsing 454 pyrosequencing technology, 8,480 and 7,474 contigs were generated after de novo assembly of RNA sequences from leaves of untreated and drought-treated plants, respectively. After clustering using TGICL and CAP3 programs, a combined assembly of all reads produced a total of 11,357 putative unique transcripts (PUTs). Functional annotation and classification of the transcripts were conducted by aligning the 11,357 PUTs against the public protein databases and nucleotide database (Nt). Between control and drought-treated plants, 1,620 differentially expressed genes (DEGs) were identified, of which 1,106 were up-regulated and 514 were down-regulated. The differential expression of twenty candidate genes in metabolic pathways and transcription factors families related to stress-response were confirmed by quantitative real-time PCR. Representatives of several large gene families, such as WRKY and P5CS, were identified and verified in A. mongolicus for the first time.ConclusionsThe additional transcriptome resources, gene expression profiles, functional annotations, and candidate genes provide a more comprehensive understanding of the stress response pathways in xeric-adapted plant species such as A. mongolicus.

Transcriptomic, biochemical and physio-anatomical investigations shed more light on responses to drought stress in two contrasting sesame genotypes

“…Globally, drought stress gradually alters gene expression in sesame 36 . Gene activities were at the lowest level after 11 days of water deprivation in the two genotypes and this may imply that a longer drought period would elicit a stronger alteration of gene expression 37 . In the other hand, it appears that a severe water deficit triggers adapted transcriptional responses in DT contrary to DS.…”

Transcriptome sequence analysis and mining of SSRs in Jhar Ber (Ziziphus nummularia (Burm.f.) Wight & Arn) under drought stress

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Tolerance strategies revealed in tree peony (Paeonia suffruticosa; Paeoniaceae) ecotypes differentially adapted to desiccation

“…The ABI StepOnePlus Real‐Time PCR System (Thermo‐Fisher Scientific) was utilized to perform the expression profile verification. The reaction was carried out as described in our previous publication (Pang et al., ), using three biological replicates per sample. The relative gene expression levels of the selected unigenes were normalized to 18S rRNA and calculated using the 2‐ΔΔCt method (Livak and Schmittgen, ).…”