, Volume 32, Issue 4, pp 600–608 | Cite as

De novo transcriptome sequencing of Monodopsis subterranea CCALA 830 and identification of genes involved in the biosynthesis of eicosapentanoic acid and triacylglycerol

  • Shivangi Shah
  • Dinabandhu Sahoo
  • Rohit Nandan Shukla
  • Girish MishraEmail author
Research Articles


Monodopsis subterranea, a unicellular yellow-green freshwater microalga, is widely known for its ability to produce high amount of therapeutically beneficial ω-3 polyunsaturated fatty acid eicosapentanoic acid (EPA; C20:5Δ5,8,11,14,17). Currently, no genomic information is available on M. subterranea despite its nutraceutical and commercial applications. Analysis on fatty acid methyl esters from M. subterranea strain CCALA 830 demonstrated accumulation of 28% EPA. In order to obtain better understanding of EPA biosynthesis and to identify genes involved in the process of lipid metabolism and accumulation in this alga, de novo transcriptome sequencing and assembly was performed using Illumina Hiseq 2000 sequencing. A total of 35,954 transcripts were obtained through final transcriptome assembly with an average transcript length of 769.36 bp. BLAST similarity searches for assembled transcripts were performed followed by annotation using Gene ontology and Kyoto Encyclopedia of Genes and Genomes orthology identifiers. Transcripts involved in lipid biosynthesis including various fatty acid desaturases and elongases involved in PUFAs biosynthesis were identified during the study. In addition, sequences for several transcription factors and a number of simple sequence repeats were also ascertained which can be used as powerful genetic markers for further genetic analysis. This study would provide a useful resource for future research on M. subterranea genome.


Monodopsis subterranea Transcriptome Illumina HiSeq 2000 Fatty acid biosynthesis TAG EPA 



Authors acknowledge financial support from the Department of Biotechnology, Ministry of Science and Technology, India (BT/PR6027/AGII/106/859/2012). SS is thankful for INSPIRE fellowship (IF140077) from the Department of Science and Technology, India.

Compliance with ethical standards

Conflict of interest

All authors declare that they have no conflict of interest.

Supplementary material

42535_2019_61_MOESM1_ESM.pdf (40 kb)
Supplementary material 1 (PDF 40 kb)


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Copyright information

© Society for Plant Research 2019

Authors and Affiliations

  1. 1.Department of BotanyUniversity of DelhiDelhiIndia
  2. 2.Institute of Bioresources and Sustainable DevelopmentImphalIndia
  3. 3.Bionivid Technology Private LimitedBengaluruIndia

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