@article{8320, abstract = {The genetic code is considered to use five nucleic bases (adenine, guanine, cytosine, thymine and uracil), which form two pairs for encoding information in DNA and two pairs for encoding information in RNA. Nevertheless, in recent years several artificial base pairs have been developed in attempts to expand the genetic code. Employment of these additional base pairs increases the information capacity and variety of DNA sequences, and provides a platform for the site-specific, enzymatic incorporation of extra functional components into DNA and RNA. As a result, of the development of such expanded systems, many artificial base pairs have been synthesized and tested under various conditions. Following many stages of enhancement, unnatural base pairs have been modified to eliminate their weak points, qualifying them for specific research needs. Moreover, the first attempts to create a semi-synthetic organism containing DNA with unnatural base pairs seem to have been successful. This further extends the possible applications of these kinds of pairs. Herein, we describe the most significant qualities of unnatural base pairs and their actual applications.}, author = {Mukba, S. A. and Vlasov, Petr and Kolosov, P. M. and Shuvalova, E. Y. and Egorova, T. V. and Alkalaeva, E. Z.}, issn = {16083245}, journal = {Molecular Biology}, number = {4}, pages = {475--484}, publisher = {Springer Nature}, title = {{Expanding the genetic code: Unnatural base pairs in biological systems}}, doi = {10.1134/S0026893320040111}, volume = {54}, year = {2020}, } @article{8321, abstract = {The genetic code is considered to use five nucleic bases (adenine, guanine, cytosine, thymine and uracil), which form two pairs for encoding information in DNA and two pairs for encoding information in RNA. Nevertheless, in recent years several artificial base pairs have been developed in attempts to expand the genetic code. Employment of these additional base pairs increases the information capacity and variety of DNA sequences, and provides a platform for the site-specific, enzymatic incorporation of extra functional components into DNA and RNA. As a result, of the development of such expanded systems, many artificial base pairs have been synthesized and tested under various conditions. Following many stages of enhancement, unnatural base pairs have been modified to eliminate their weak points, qualifying them for specific research needs. Moreover, the first attempts to create a semi-synthetic organism containing DNA with unnatural base pairs seem to have been successful. This further extends the possible applications of these kinds of pairs. Herein, we describe the most significant qualities of unnatural base pairs and their actual applications.}, author = {Mukba, S. A. and Vlasov, Petr and Kolosov, P. M. and Shuvalova, E. Y. and Egorova, T. V. and Alkalaeva, E. Z.}, issn = {00268984}, journal = {Molekuliarnaia biologiia}, number = {4}, pages = {531--541}, publisher = {Russian Academy of Sciences}, title = {{Expanding the genetic code: Unnatural base pairs in biological systems}}, doi = {10.31857/S0026898420040126}, volume = {54}, year = {2020}, } @article{8700, abstract = {Translation termination is a finishing step of protein biosynthesis. The significant role in this process belongs not only to protein factors of translation termination but also to the nearest nucleotide environment of stop codons. There are numerous descriptions of stop codons readthrough, which is due to specific nucleotide sequences behind them. However, represented data are segmental and don’t explain the mechanism of the nucleotide context influence on translation termination. It is well known that stop codon UAA usage is preferential for A/T-rich genes, and UAG, UGA—for G/C-rich genes, which is related to an expression level of these genes. We investigated the connection between a frequency of nucleotides occurrence in 3' area of stop codons in the human genome and their influence on translation termination efficiency. We found that 3' context motif, which is cognate to the sequence of a stop codon, stimulates translation termination. At the same time, the nucleotide composition of 3' sequence that differs from stop codon, decreases translation termination efficiency.}, author = {Sokolova, E. E. and Vlasov, Petr and Egorova, T. V. and Shuvalov, A. V. and Alkalaeva, E. Z.}, issn = {16083245}, journal = {Molecular Biology}, number = {5}, pages = {739--748}, publisher = {Springer Nature}, title = {{The influence of A/G composition of 3' stop codon contexts on translation termination efficiency in eukaryotes}}, doi = {10.1134/S0026893320050088}, volume = {54}, year = {2020}, } @article{8701, abstract = {Translation termination is a finishing step of protein biosynthesis. The significant role in this process belongs not only to protein factors of translation termination but also to the nearest nucleotide environment of stop codons. There are numerous descriptions of stop codons readthrough, which is due to specific nucleotide sequences behind them. However, represented data are segmental and don’t explain the mechanism of the nucleotide context influence on translation termination. It is well known that stop codon UAA usage is preferential for A/T-rich genes, and UAG, UGA—for G/C-rich genes, which is related to an expression level of these genes. We investigated the connection between a frequency of nucleotides occurrence in 3' area of stop codons in the human genome and their influence on translation termination efficiency. We found that 3' context motif, which is cognate to the sequence of a stop codon, stimulates translation termination. At the same time, the nucleotide composition of 3' sequence that differs from stop codon, decreases translation termination efficiency.}, author = {Sokolova, E. E. and Vlasov, Petr and Egorova, T. V. and Shuvalov, A. V. and Alkalaeva, E. Z.}, issn = {00268984}, journal = {Molekuliarnaia biologiia}, number = {5}, pages = {837--848}, publisher = {Russian Academy of Sciences}, title = {{The influence of A/G composition of 3' stop codon contexts on translation termination efficiency in eukaryotes}}, doi = {10.31857/S0026898420050080}, volume = {54}, year = {2020}, }