Differential Expression Pattern of linc-ROR Spliced Variants in Pluripotent and Non-Pluripotent Cell Lines

Document Type : Original Article

Authors

1 Molecular Genetics Department, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran

2 Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK

3 Department of Biomolecular Sciences, University of Urbino, Via Saffi Urbino, Italy

4 Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran

5 Department of Biology, Science and Research branch, Islamic Azad University, Tehran, Iran

Abstract

Objective: The human large intergenic non-coding RNA-regulator of reprogramming program (linc-ROR) is known as a
stem cell specific linc-RNA. linc-ROR counteracts differentiation via sequestering microRNA-145 (miR-145) that targets OCT4 transcript. Despite the research on the expression and function, the exact structure of Linc-ROR transcripts is not clear. Considering the contribution of alternative splicing in transcripts structures and function, identifying different spliced variants of linc-ROR is necessary for further functional analyses. We aimed to find the alternatively spliced transcripts of linc-ROR and investigate their expression pattern in stem and cancer cell lines and during neural differentiation of NT2 cells as a model for understanding linc-ROR role in stem cell and differentiation.
Materials and Methods: In this experimental study, linc-ROR locus was scanned for identifying novel exons. Different primer sets were used to detect new spliced variants by reverse transcription polymerase chain reaction (RT-PCR) and direct sequencing. Quantitative PCR (qPCR) and RT-PCR were employed to profile expression of linc-ROR transcripts in different cell lines and during neural differentiation of stem cells.
Results: We could discover 13 novel spliced variants of linc-ROR harboring unique array of exons. Our work uncovered
six novel exons, some of which were the product of exonized transposable elements. Monitoring expression profile of the linc-ROR spliced variants in a panel of pluripotent and non-pluripotent cells exhibited that all transcripts were primarily expressed in pluripotent cells. Moreover, the examined linc-ROR spliced variants showed a similar downregulation during neural differentiation of NT2 cells.
Conclusion: Altogether, our data showed despite the difference in the structure and composition of exons, various spliced variants of linc-ROR showed similar expression pattern in stem cells and through differentiation.

Keywords


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