Many theories thought that present-day tRNA sequences evolved from some short RNA hairpins which contain a simple stem-loop structure. To find out these significant fragment sequences, the repeated sequences of differ...Many theories thought that present-day tRNA sequences evolved from some short RNA hairpins which contain a simple stem-loop structure. To find out these significant fragment sequences, the repeated sequences of different length within 3420 tRNA sequences are counted and analyzed. The results show that: 1) the probability of occurrence P(i) with the given repeated sequences i follows a power-law distribution when the length K of repeated sequences is longer than four bases, and in this case, the total number N(n) of occurrence with the repeated times n follows a power-law distribution too;2) the sequence of the length K which repeats the largest times is just only sequence of the length K-b wobbling b bases on its left or right side (b varies between 1 and K-1);3) the same repeated sequences are found nearly at the identical site in different tRNA sequences as the length K of repeated sequences is longer than five bases. Then a hypothesis of the origin and evolution mechanisms of tRNA sequences is proposed and discussed.展开更多
Various physical properties such as dipole moment, heat of formation and energy of the most stable formation of nucleotides and bases were calculated by PM3 (modified neglect of diatomic overlap, parametric method num...Various physical properties such as dipole moment, heat of formation and energy of the most stable formation of nucleotides and bases were calculated by PM3 (modified neglect of diatomic overlap, parametric method number 3) and AM1 (austin model 1) methods. As distinct from previous calculations, for nucleotides the interaction with neighbours is taken into account up to gradient of convergence equaling 1. The dependencies of these variables from the place in the codon and the de- terminative degree were obtained. The difference of these variables for codons and anticodons is shown.展开更多
Dear Editor,Transfer RNA(tRNA)is an indispensable adaptor molecule in the messenger RNA(mRNA)translation machinery,facilitating the conversion of genetic information encoded in mRNA into functional proteins.Numerous p...Dear Editor,Transfer RNA(tRNA)is an indispensable adaptor molecule in the messenger RNA(mRNA)translation machinery,facilitating the conversion of genetic information encoded in mRNA into functional proteins.Numerous posttranscriptional modifications in tRNA have been identified,which play significantroles in modulating tRNA folding,biochemical stability,amino-acylation,and codon–anticodon interaction(Suzuki,2021).TRMT10A,the mammalian homolog of Trm10,incorporates N1-methylguanosine modification at position 9(m^(1)G9)of various cytoplasmic tRNAs,including tRNAGln and tRNAIniMeth(Vilardo et al.,2020).Mutations in human TRMT10A,which is enriched in pancreatic islets and brain(Igoillo-Esteve et al.,2013),are often associated with microcephaly,intellectual disability,early-onset diabetes,and short stature(Igoillo-Esteve et al.,2013;Uçan Tokuçet al.,2024).展开更多
文摘Many theories thought that present-day tRNA sequences evolved from some short RNA hairpins which contain a simple stem-loop structure. To find out these significant fragment sequences, the repeated sequences of different length within 3420 tRNA sequences are counted and analyzed. The results show that: 1) the probability of occurrence P(i) with the given repeated sequences i follows a power-law distribution when the length K of repeated sequences is longer than four bases, and in this case, the total number N(n) of occurrence with the repeated times n follows a power-law distribution too;2) the sequence of the length K which repeats the largest times is just only sequence of the length K-b wobbling b bases on its left or right side (b varies between 1 and K-1);3) the same repeated sequences are found nearly at the identical site in different tRNA sequences as the length K of repeated sequences is longer than five bases. Then a hypothesis of the origin and evolution mechanisms of tRNA sequences is proposed and discussed.
文摘Various physical properties such as dipole moment, heat of formation and energy of the most stable formation of nucleotides and bases were calculated by PM3 (modified neglect of diatomic overlap, parametric method number 3) and AM1 (austin model 1) methods. As distinct from previous calculations, for nucleotides the interaction with neighbours is taken into account up to gradient of convergence equaling 1. The dependencies of these variables from the place in the codon and the de- terminative degree were obtained. The difference of these variables for codons and anticodons is shown.
基金Supplementary material is available at Journal of Molecular Cell Biology online.This study was supported by grants from the National Natural Science Foundation of China(82230075 to D.G.32270159 to J.W.)+2 种基金Guangdong Basic and Applied Basic Research Foundation(2023A1515012613 to J.W.)Shenzhen Science and Technology Program(JCYJ20200109142201695 and KQTD20180411143323605 to D.G.,JCYJ20220530145608018 to J.W.)Shenzhen Key Laboratory of Systems Medicine for Inflammatory Diseases(ZDSYS20220606100803007 to J.W.).
文摘Dear Editor,Transfer RNA(tRNA)is an indispensable adaptor molecule in the messenger RNA(mRNA)translation machinery,facilitating the conversion of genetic information encoded in mRNA into functional proteins.Numerous posttranscriptional modifications in tRNA have been identified,which play significantroles in modulating tRNA folding,biochemical stability,amino-acylation,and codon–anticodon interaction(Suzuki,2021).TRMT10A,the mammalian homolog of Trm10,incorporates N1-methylguanosine modification at position 9(m^(1)G9)of various cytoplasmic tRNAs,including tRNAGln and tRNAIniMeth(Vilardo et al.,2020).Mutations in human TRMT10A,which is enriched in pancreatic islets and brain(Igoillo-Esteve et al.,2013),are often associated with microcephaly,intellectual disability,early-onset diabetes,and short stature(Igoillo-Esteve et al.,2013;Uçan Tokuçet al.,2024).
