Functional Analysis of Circular RNAs

  • Shanmugapriya
  • Hisham Alkatib Huda
  • Soundararajan Vijayarathna
  • Chern Ein Oon
  • Yeng Chen
  • Jagat R. Kanwar
  • Mei Li Ng
  • Sreenivasan Sasidharan
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1087)


Circular RNAs characterize a class of widespread and diverse endogenous RNAs which are non-coding RNAs that are made by back-splicing events and have covalently closed loops with no polyadenylated tails. Various indications specify that circular RNAs (circRNAs) are plentiful in the human transcriptome. However, their participation in biological processes remains mostly undescribed. To date thousands of circRNAs have been revealed in organisms ranging from Drosophila melanogaster to Homo sapiens. Functional studies specify that these transcripts control expression of protein-coding linear transcripts and thus encompass a key component of gene expression regulation. This chapter provide a comprehensive overview on functional validation of circRNAs. Furthermore, we discuss the recent modern methodologies for the functional validation of circRNAs such as RNA interference (RNAi) gene silencing assay, luciferase reporter assays, circRNA gain-of-function investigation via overexpression of circular transcript assay, RT-q-PCR quantification, and other latest applicable assays. The methods described in this chapter are demonstrated on the cellular model.


CircRNAs Functional validation Cellular model 



Shanmugapriya was supported by the Graduate Research Assistance Scheme from Universiti Sains Malaysia, Malaysia.

Competing Financial Interests

The authors declare no competing financial interests.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Shanmugapriya
    • 1
  • Hisham Alkatib Huda
    • 1
  • Soundararajan Vijayarathna
    • 1
  • Chern Ein Oon
    • 1
  • Yeng Chen
    • 2
  • Jagat R. Kanwar
    • 3
  • Mei Li Ng
    • 4
  • Sreenivasan Sasidharan
    • 1
  1. 1.Institute for Research in Molecular Medicine (INFORMM)Universiti Sains MalaysiaPulau PinangMalaysia
  2. 2.Faculty of Dentistry, Dental Research & Training Unit, and Oral Cancer Research and Coordinating Centre (OCRCC)University of MalayaKuala LumpurMalaysia
  3. 3.Faculty of Health, Nanomedicine-Laboratory of Immunology and Molecular Biomedical Research (LIMBR), School of Medicine (SoM)Deakin UniversityGeelongAustralia
  4. 4.Integrative Medicine Cluster, Advanced Medical and Dental Institute (AMDI)Universiti Sains MalaysiaPulau PinangMalaysia

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