Summary:
In this diploma thesis, cyclic RNAs of the PRMT1 gene in human colorectal cancer cells was studied. This gene encodes the protein arginine N-methyltransferase 1 an enzyme that acts as histone methyltransferase specific for histone H4 in eukaryotic cells. The methylation of the histone from the enzyme induces the remodeling of chromatin, affecting a plurality of significant cellular functions.
Circular RNA is a type of monoclonal RNA which forms a continuous loop and is produced by an abnormal splicing event. CircRNAs has been found to be involved in cellular regulation.
Initially, expression analysis of the PRMT1 gene was performed in 55 cell lines of different tissue origin. Then, PCR was performed with divergent - primers in some of these series, with the aim of establishing the existence of cyclic RNAs. We chose to continue with lines from colorectal cancer. A pool cDNA was created from 6 lines of colorectal cancer (DLD-1, Colo 205, HT-29, RKO, Caco-2, HCT-116), which was used as a template for nested PCR. PCR products were electrophoresed on agarose gel. The zone of interest observed was purified using microparticular columns and sequenced by Sanger, resulting in the finding of a new cyclic RNA consisting of the 1st exon, the entire 4th exon and a part of the 5th exon of PRMT1.
Therefore, this study led to finding a new molecule that was further studied in the present work with bioinformatical methods. More specifically, we looked for possible interactions of this cyclic molecule with miRNAs as well as proteins. In addition, open reading and internal ribosome binding frames was searched.
Nevertheless, this thesis is just a first approach, additional experiments that will be related to the further study of this circular RNA are necessary.
