GCRIS

Now showing 1 - 3 of 3

Examination of Stable Intronic Sequence Rna Profile Under Apoptotic Conditions
(Izmir Institute of Technology, 2022) Kara, Merve; Akgül, Bünyamin
Apoptosis is a process of programmed cell death. Cisplatin, a chemotherapeutic drug, activates intrinsic pathway of apoptosis while TNF-alpha, a death ligand, activates the extrinsic pathway of apoptosis. Noncoding RNAs involve in regulation of apoptotic pathways at post-transcriptional level. Stable intronic sequence RNAs (sisRNAs) are the novel class of non-coding RNAs which can be generated by splicing- dependent and independent mechanisms. sisRNAs transcribed from their intronic promoter may contain 5’ cap and polyA tail. Despite the reports of several studies about sisRNAs in Xenopus and Drosophila, a genome-wide profile of sisRNAs in human is lacking. Therefore, we aimed to identify sisRNAs profile that are transcribed from their intronic promoter under cisplatin- and TNF-alpha- mediated apoptosis conditions. In this thesis study, the deep sequencing of total RNA, polyA + and polyA eliminated fractions from cisplatin-, TNFalpha-, DMSO-treated cells were performed. Differentially expressed intronic transcripts were analysed by DE-kupl algorithm. The intronic transcripts both in total RNA and polyA + RNA fractions but not in polyA eliminated fractions were screened visually on Integrated Genome Viewer (IGV) and selected as sisRNA candidateS. 48 sisRNA candidates were detected in cisplatin-treated data while 33 sisRNA candidates were detected in TNF-alpha- treated data. 5’ and 3’ RACE PCRs were performed for determination of transcriptional units of sisRNA candidates. Overexpression of sisRDOCK7-IT1 caused 8.09% increase in total apoptosis of HeLa cells in 48 hours. sisRDOCK7-IT1 triggers the activation of apoptosis but the mechanism of its induction of apoptosis is still unknown.
Investigation of Long Non-Coding Rna and Chromatin Interactions in Hela Cells
(Izmir Institute of Technology, 2022) Atbinek, Melis; Akgül, Bünyamin
The DNA in the cells is surrounding histone proteins to form nucleosomes. The structure is packed further into chromatin. The chromatin structure is dynamic and flexible. It is regulated by many factors including long non-coding RNAs (lncRNAs). LncRNAs are a class of non-coding RNAs, transcripts that do not encode protein. They are longer than 200 nucleotides and might contain a polyA tail and a 5’ cap. Thus, they are localized in the nucleus. lncRNAs interact with chromatin in two ways, indirect and direct. Direct interaction occurs via two mechanisms: R-loop and triplex formation. These interactions affect the folding of chromatin inducing gene expression under various cellular conditions. LncRNAs interacting with chromatin regulating genes are found in HEK cells. Thus, it is hypothesized that lncRNA – chromatin interactions may differ in cancerous cells as well. In this study, the iMARGI method is optimized to be used in adenocarcinoma HeLa cells. The chromatin digestion and incubation conditions are adjusted to give optimal results for HeLa cells. iMARGI is a recently developed method employed to investigate such interactions in a genome-wide manner. iMARGI allows the isolation of all lncRNAs interacting with the whole genome. The interacting RNA – DNA molecules are pulled down with streptavidin conjugated beads after linker ligation. The chimeric molecules are amplified with PCR forming lncRNA – chromatin libraries of HeLa cells. In the future, new libraries can be formed after inducing apoptosis in HeLa cells. Identification of lncRNAs involved in chromatin remodeling in apoptotic conditions can facilitate new therapeutic methods for fighting tumor initiation and development.
Investigation of the Interaction Between Dr5-As Long Noncoding Rna and Caprin1 Protein
(Izmir Institute of Technology, 2022) Kaçar, Vahide İlayda; Akgül, Bünyamin
Cell proliferation is the crucial process for many physiological incidents such as tissue and organ development, wound healing, and immune system reactions. It is achieved by the growth and division of cells in a multicellular organism. Investigation of molecules involved in the regulation of cell cycle mechanism provides insight into reasons and treatments of the diseases such as cancer. In recent years, information that acquired from deep sequencing reveals that several proteins and non-coding RNAs have crucial role in the regulation of cell cycle and proliferation. Death receptor 5 antisense (DR5-AS) is a novel long non-coding RNA (lncRNA) transcript that is cisplatin inducible and is involved in modulation of cell proliferation and cell cycle in HeLa cells. When DR5-AS lncRNA was knocked down, the morphology of HeLa cells became spherical without inducing apoptosis. Although this lncRNA reduces cell proliferation via a cell cycle arrest at S and G2/M phases, mechanism behind this cell cycle arrest is not known. lncRNAs work in complexes with RNA, DNA, and protein interactions in the cell. There are several experimental and bioinformatical approaches to investigate RNA: protein interactions such as PAR-CLIP. In this approach, proximal protein and RNAs are covalently bonded with UV radiation. Then this complex is immunoprecipitated with specific antibodies. According to PAR-CLIP data of DR5-AS lncRNA, CAPRIN1 is a cell cycle associated protein that has the highest interaction score. The results suggest that CAPRIN1 and DR5-AS work reversely in cell proliferation although under the cisplatin treatment, CAPRIN1 enhances the expression of DR5-AS lncRNA. All these observations were confirmed by many quantitative experiments. Conclusively, this study provides a clue about how DR5-AS lncRNA might regulate cell cycle and proliferation through CAPRIN1 protein.

Master Degree / Yüksek Lisans Tezleri

Browse

Filters

Settings

Sort By

Results per page

Search Results