The origin and evolution of life on the planet is one of the most intriguing challenges in life sciences and, for some researchers, it is centered in the origin of the genetic code. Many hypotheses about the origin and evolution of tRNA have been proposed and in this work a new suggestion is proposed based on the reconstruction of tRNA ancestor sequences. Ancestral sequences of 22 types of tRNA molecules were built by maximum likelihood from 9758 sequences currently reported from different organisms. Phylogenetic analysis showed that the main force for evolutionary diversification of tRNA molecules was a change in the second base of the anticodon. The data revealed that diversification is not correlated with the characteristic of the specified amino acid, indicating that the correlation between tRNA and amino acid was given indirectly, and possibly should have been mediated by proto-aminoacyl-tRNA synthetases.
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http://dx.doi.org/10.1016/j.jtbi.2013.06.033 | DOI Listing |
Annu Rev Entomol
January 2025
Department of Biology and Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico.
Novel traits in the order Lepidoptera include prolegs in the abdomen of larvae, scales, and eyespot and band color patterns in the wings of adults. We review recent work that investigates the developmental origin and diversification of these four traits from a gene-regulatory network (GRN) perspective. While prolegs and eyespots appear to derive from distinct ancestral GRNs co-opted to novel body regions, scales derive from in situ modifications of a sensory bristle GRN.
View Article and Find Full Text PDFElucidating the genetic contributions to Parkinson's disease (PD) etiology across diverse ancestries is a critical priority for the development of targeted therapies in a global context. We conducted the largest sequencing characterization of potentially disease-causing, protein-altering and splicing mutations in 710 cases and 11,827 controls from genetically predicted African or African admixed ancestries. We explored copy number variants (CNVs) and runs of homozygosity (ROHs) in prioritized early onset and familial cases.
View Article and Find Full Text PDFAttention-deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder, but its genetic architecture remains incompletely characterized. Rare coding variants, which can profoundly impact gene function, represent an underexplored dimension of ADHD risk. In this study, we analyzed large-scale DNA sequencing datasets from ancestrally diverse cohorts and observed significant enrichment of rare protein-truncating and deleterious missense variants in highly evolutionarily constrained genes.
View Article and Find Full Text PDFPeerJ
January 2025
Department of Biological Science, University of Ulsan, Ulsan, Republic of South Korea.
The genus , a group of ciliated protists, has attracted attention as a model organism due to its widespread distribution and ease of cultivation. This study examines the evolutionary patterns of the SSU rRNA secondary structure within this genus, aiming to elucidate its role in supporting evolutionary relationships and uncovering cryptic species. By predicting the secondary structure of SSU rRNA and applying the CBC (Compensatory Base Change) concept analysis, we examined 69 species of the genus , with 57 SSU rRNA gene sequences retrieved from GenBank and 12 newly sequenced specimens from South Korea.
View Article and Find Full Text PDFChemSusChem
January 2025
Nanjing Normal University, School of Food Science and Pharmaceutical Engineering, No. 2 Xuelin Road, 210023, Nanjing, CHINA.
Beyond directed evolution, ancestral sequence reconstruction (ASR) has emerged as a powerful strategy for engineering proteins with superior functional properties. Herein, we harnessed ASR to uncover robust PET hydrolase variants, expanding the repertoire of PET-degrading enzymes and providing deeper insights into the underlying mechanisms of PET hydrolysis. As a result, ASR1-PETase, featuring a unique cysteine catalytic site, was discovered.
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