Complementary DNA library construction and expressed sequence tag analysis of an Arctic moss, Aulacomnium turgidum

Inha University Department of Biological Engineering Incheon 402-751 Republic of Korea
Polar Biology (Impact Factor: 1.59). 05/2009; 33(5):617-626. DOI: 10.1007/s00300-009-0737-8


Unique physiological and metabolic properties of Arctic mosses are responsible for their acclimation to the inclement polar
environment. To perform transcriptome analysis of an Arctic moss species adapted to polar conditions, we constructed a complementary
DNA (cDNA) library using total high-quality RNA extracted from the moss species Aulacomnium turgidum. The library consisted of 1.81×106 of independent clones with 97.41% of recombinants. A total of 509 cDNA clones were sequenced. After eliminating poor quality
sequences, vector trimming and clustering, 360 unigenes consisting of 33 contigs and 327 singletons were identified. Basic
Local Alignment Search Tool X searches generated 245 significant hits (E value <10−5). For further Gene Ontology analysis, 158 unigenes were annotated and classified with terms for molecular function, biological
process and cellular component. Among the expressed sequence tags, seven genes were selected based on their putative roles
in stress response, and they showed enhanced transcripts level under various abiotic stresses such as low temperature, heat
and high-salinity. Also, two rare-cold-inducible genes showed different expression patterns under low temperature and UV-B
treatment, indicating their distinct roles in adaptation to Arctic environment. Although experiments have been conducted on
a limited scale, this study provides useful information for better understanding the mechanism of stress acclimation of polar
mosses and material basis for potential genomic modification for higher plants to increase stress tolerance.

KeywordsArctic moss-
Aulacomnium turgidum
-Expressed sequence tags (ESTs)-Gene Ontology (GO)

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Available from: Hyoungseok Lee, May 16, 2014
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    • "Total RNA was extracted from liquid nitrogen ground algae powder using cetyl trimethylammonium bromide (CTAB) extraction buffer composed of 2% CTAB, 1% polyvinylpyrrolidone K-30 (soluble), 100 mM Tris–HCl (pH 8.0), 20 mM EDTA, 1.4 M NaCl, 0.5 g/L spermidine (free acid), 2% β-mercaptoethanol (added just before use; Liu et al. 2010). After adding 0.5 mL CTAB buffer (2% β-ME) to the ground powder, the samples were incubated at 60°C for 10 min and mixed well by vortexing. "
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