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Abstract
Analysis of the Role of Aminoacyl tRNA Synthetase Genes in Global Protein Synthesis and mRNA Specific Regulation of Translation in Cancer Cells
Elyse Nguyen, Depts. of Biology and Chemistry, Dipak Poria, & Esta Sterneck, with Dr. Sarah Williams, Dept. of Forensic Science
Coordinated control of transcription and translation of gene expression impels cellular fate decision under different microenvironmental stresses. Cancer cells often usurp these regulatory machineries to adapt under microenvironmental stress or under therapeutic intervention. The transcription factor CEBPδ is induced by various stressors and mediates cellular adaptation and survival. RNA-seq analysis of a CEBPD-silenced human melanoma cell line, MB-435s, showed decreased expression of 12 aminoacyl-tRNA synthetase (aaRS) genes. Our group recently found that deletion of CEBPD by CRISPR/Cas9 (CEBPD-KO) compromised aminoacyl tRNA synthetase (aaRS) expression and global protein synthesis. However, despite this decrease in global protein production, the synthesis of certain proteins, such as ATF4, which promotes survival and/or death under stress conditions, is increased. Aminoacyl tRNA synthetases are essential enzymes in the process of protein synthesis which catalyze the addition of appropriate amino acid to its corresponding tRNA, and therefore act as a rate limiting step in cellular protein synthesis. In the current project, we sought to investigate the effect of silencing of specific aaRS genes, glutamyl-prolyl-tRNA synthetase (EPRS) and valyl-tRNA synthetase (VARS) on global protein translation and ATF4 expression. To address this question, we silenced the EPRS and VARS gene expression using two independent short-hairpin-RNA (shRNA) targeting two different regions of EPRS and VARS mRNAs in MB-435s cells. Silencing of EPRS gene showed compensatory upregulation of VARS and vice versa. Interestingly, our preliminary data suggested an upregulation of global protein synthesis after EPRS and VARS silencing in MB435s cells measured by puromycin pulse labelling. Ongoing experiments to validate the preliminary data and ATF4 expression will be discussed.
Publication Date
2020
Faculty Advisor/Mentor
Sarah J. Seashols-Williams, Ph.D
Sponsorship
Virginia Commonwealth University. Undergraduate Research Opportunities Program
Is Part Of
VCU Undergraduate Research Posters
Rights
© The Author(s)