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Information × Registration Number 0225U001366, (0119U103634) , R & D reports Title Molecular mechanisms for quality control of translation with non-proteinogenic amino acids participation popup.stage_title Вивчення помилкового включення норваліну, норлейцину та гомоцистеїну на місце лейцину в білки клітинних ліній людини у середовищі з підвищеною концентрацією відповідних амінокислот. Head Tukаlo Mykhаilo A., Доктор біологічних наук Registration Date 30-01-2025 Organization Institute of Molecular Biology and Genetics of NAS of Ukraine popup.description1 The goal of this project is to study the structural and conformational determinants of tRNAs, human leucyl-tRNA synthetase and alanyl-tRNA synthetases from various species that exclude the participation of non-proteinogenic amino acids such as norleucine, norvaline, homocysteine and D-alanine, in protein biosynthesis. The mechanisms of stereospecificity control in translation of genetic information have not yet been elucidated. Therefore, the ability of AlaRS and ProRS from different species (E. coli, Enterococcus faecalis and Homo sapiens) to edit D-amino acids will be studied. Additionally, separate trans-editing factor AlaX will be examined. The comprehensive approach, combining genetic engineering, biochemical, biophysical and molecular dynamics methods and quantum chemical calculations, will be applied. The study of the influence of incorporation of norvaline, norleucine and homocysteine into proteins on the growth of normal and cancer cells will be performed. The results of our investigations will be used for the search of new antibiotics against human pathogens and new drugs against cancer. Additionally, they also provide the basis for the creation of new orthologous tRNA-ARSase pairs for synthetic biology. popup.description2  Error-free translation of a DNA sequence is key to the functioning of any cell. Aminoacyl-tRNA synthetases are responsible for the correct expression of the genetic code, which ensure the specific attachment of a homologous amino acid to the corresponding tRNA. Aminoacylation of tRNA is an important part of the multi-step quality control process in the cell, and a decrease in the accuracy of this stage in protein biosynthesis can have catastrophic consequences. More than half of ARSases can mistakenly activate amino acids that are similar to their homologous ones. These enzymes have acquired editing mechanisms in the process of evolution, with the help of which errors are corrected, which prevents their incorporation into proteins during translation. The editing activity of ARSases can occur at each of the two stages of tRNA aminoacylation. At the same time, similar information for non-proteinogenic amino acids, the erroneous incorporation of which into proteins poses an even greater threat to a living cell, remains unclear. However, in eukaryotic organisms, the quality control of translation of non-proteinogenic amino acids has not been studied. Among the amino acids, leucine is known to be a potential signaling molecule that regulates growth and metabolism by activating the intracellular multimolecular signaling complex (mTORC1), which includes the mammalian target of rapamycin kinase. However, little attention has been paid to the effect of non-proteinogenic leucine analogs on the functioning of leucine-dependent signaling pathways in human cells. During the stage, the editing activity of human leucyl-tRNA synthetases was analyzed for D-leucine, D-norvaline, and D-homocysteine, as well as T. thermophilus to compare the editing activity of the eukaryotic enzyme with the prokaryotic one. The absence of editing activity of T. thermophilus and human LeuRS for D-amino acids was found. In addition, the effect of non-proteinogenic amino acids (norvaline, norleucine and Product Description popup.authors Hudzera Olha Y. Kovalenko Oksana P. Skydanovych Oleksandra I. Yaremchuk Hanna D. popup.nrat_date 2025-01-30 Close