, Volume 248, Issue 2, pp 347–367 | Cite as

Leaf lipidome and transcriptome profiling of Portulaca oleracea: characterization of lysophosphatidylcholine acyltransferase

  • Varadarajan Venkateshwari
  • Anitha Vijayakumar
  • Arun Kumar Vijayakumar
  • L. Prasanna Anjaneya Reddy
  • Malathi Srinivasan
  • Ram RajasekharanEmail author
Original Article


Main conclusion

Portulaca leaves serve as an alternative bioresource for edible PUFAs. Transcriptome data provide information to explore Portulaca as a model system for galactolipids, leaf lipid metabolism, and PUFA-rich designer lipids.

Poly-unsaturated fatty acids (PUFAs) are gaining importance due to their innumerable health benefits, and hence, understanding their biosynthesis in plants has attained prominence in recent years. The most common source of PUFAs is of marine origin. Although reports have identified Portulaca oleracea (purslane) as a leaf source of omega-3 fatty acids in the form of alpha-linolenic acid (ALA), the mechanism of ALA accumulation and its distribution into various lipids has not been elucidated. Here, we present the lipid profiles of leaves and seeds of several accessions of P. oleracea. Among the nineteen distinct accessions, the RR04 accession has the highest amount of ALA and is primarily associated with galactolipids. In addition, we report the transcriptome of RR04, and we have mapped the potential genes involved in lipid metabolism. Phosphatidylcholine (PC) is the major site of acyl editing, which is catalyzed by lysophosphatidylcholine acyltransferase (LPCAT), an integral membrane protein that plays a major role in supplying oleate to the PC pool for further unsaturation. Our investigations using mass spectrometric analysis of leaf microsomal fractions identified LPCAT as part of a membrane protein complex. Both native and recombinant LPCAT showed strong acyltransferase activity with various acyl-CoA substrates. Altogether, the results suggest that ALA-rich glycerolipid biosynthetic machinery is highly active in nutritionally important Portulaca leaves. Furthermore, lipidome, transcriptome, and mass spectrometric analyses of RR04 provide novel information for exploring Portulaca as a potential resource and a model system for studying leaf lipid metabolism.


Alpha-linolenic acid Galactolipids Triacylglycerol Phosphatidylcholine Fatty acid Microsomal membrane 



We thank the Kansas Lipidomics Research Center Analytical Laboratory, Kansas State University for analyzing the plant lipid samples presented in this paper. We acknowledge Bionivid Technology Private Limited Bangalore, India for sequencing and analysis.

Funding information

This work was supported by LIPIC, 12th five year plan, CSIR, New Delhi, India. Additional support was provided by JC Bose National Fellowship from the Department of Science and Technology, New Delhi for R.R. V.V. was supported by CSIR-Senior Research Fellowship.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

425_2018_2908_MOESM1_ESM.docx (6 mb)
Supplementary material 1 (DOCX 6105 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Varadarajan Venkateshwari
    • 1
    • 3
  • Anitha Vijayakumar
    • 1
  • Arun Kumar Vijayakumar
    • 2
  • L. Prasanna Anjaneya Reddy
    • 1
  • Malathi Srinivasan
    • 1
    • 3
  • Ram Rajasekharan
    • 1
    • 3
    Email author
  1. 1.Department of Lipid ScienceCentral Food Technological Research InstituteMysoreIndia
  2. 2.Food Safety and Analytical Quality Control DepartmentCentral Food Technological Research InstituteMysoreIndia
  3. 3.Academy of Scientific and Innovative ResearchNew DelhiIndia

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