scholarly journals Evolution of selenophosphate synthetases: emergence and relocation of function through independent duplications and recurrent subfunctionalization

2015 ◽  
Author(s):  
Marco Mariotti ◽  
Didac Santesmasses ◽  
Salvador Capella-Gutierrez ◽  
Andrea Mateo ◽  
Carme Arnan ◽  
...  

SPS catalyzes the synthesis of selenophosphate, the selenium donor for the synthesis of the amino acid selenocysteine (Sec), incorporated in selenoproteins in response to the UGA codon. SPS is unique among proteins of the selenoprotein biosynthesis machinery in that it is, in many species, a selenoprotein itself, although, as in all selenoproteins, Sec is often replaced by cysteine (Cys). In metazoan genomes we found, however, SPS genes with lineage specific substitutions other than Sec or Cys. Our results show that these non-Sec, non-Cys SPS genes originated through a number of independent gene duplications of diverse molecular origin from an ancestral selenoprotein SPS gene. Although of independent origin, complementation assays in fly mutants show that these genes share a common function, which most likely emerged in the ancestral metazoan gene. This function appears to be unrelated to selenophosphate synthesis, since all genomes encoding selenoproteins contain Sec or Cys SPS genes (SPS2), but those containing only non-Sec, non-Cys SPS genes (SPS1) do not encode selenoproteins. Thus, in SPS genes, through parallel duplications and subsequent convergent subfunctionalization, two functions initially carried by a single gene are recurrently segregated at two different loci. RNA structures enhancing the readthrough of the Sec-UGA codon in SPS genes, which may be traced back to prokaryotes, played a key role in this process. The SPS evolutionary history in metazoans constitute a remarkable example of the emergence and evolution of gene function. We have been able to trace this history with unusual detail thanks to the singular feature of SPS genes, wherein the amino acid at a single site determines protein function, and, ultimately, the evolutionary fate of an entire class of genes.

Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1827
Author(s):  
Ana R. Cardoso ◽  
Mónica Lopes-Marques ◽  
Manuela Oliveira ◽  
António Amorim ◽  
Maria J. Prata ◽  
...  

In the past few years, there has been an increasing neuroscientific interest in understanding the function of mammalian chromodomains helicase DNA-binding (CHD) proteins due to their association with severe developmental syndromes. Mammalian CHDs include nine members (CHD1 to CHD9), grouped into subfamilies according to the presence of specific functional domains, generally highly conserved in evolutionary terms. Mutations affecting these domains hold great potential to disrupt protein function, leading to meaningful pathogenic scenarios, such as embryonic defects incompatible with life. Here, we analysed the evolution of CHD proteins by performing a comparative study of the functional domains of CHD proteins between orthologous and paralogous protein sequences. Our findings show that the highest degree of inter-species conservation was observed at Group II (CHD3, CHD4, and CHD5) and that most of the pathological variations documented in humans involve amino acid residues that are conserved not only between species but also between paralogs. The parallel analysis of both orthologous and paralogous proteins, in cases where gene duplications have occurred, provided extra information showing patterns of flexibility as well as interchangeability between amino acid positions. This added complexity needs to be considered when the impact of novel mutations is assessed in terms of evolutionary conservation.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Pablo Mier ◽  
Miguel A. Andrade-Navarro

Abstract According to the amino acid composition of natural proteins, it could be expected that all possible sequences of three or four amino acids will occur at least once in large protein datasets purely by chance. However, in some species or cellular context, specific short amino acid motifs are missing due to unknown reasons. We describe these as Avoided Motifs, short amino acid combinations missing from biological sequences. Here we identify 209 human and 154 bacterial Avoided Motifs of length four amino acids, and discuss their possible functionality according to their presence in other species. Furthermore, we determine two Avoided Motifs of length three amino acids in human proteins specifically located in the cytoplasm, and two more in secreted proteins. Our results support the hypothesis that the characterization of Avoided Motifs in particular contexts can provide us with information about functional motifs, pointing to a new approach in the use of molecular sequences for the discovery of protein function.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Erna Davydova ◽  
Tadahiro Shimazu ◽  
Maren Kirstin Schuhmacher ◽  
Magnus E. Jakobsson ◽  
Hanneke L. D. M. Willemen ◽  
...  

AbstractPost-translational methylation plays a crucial role in regulating and optimizing protein function. Protein histidine methylation, occurring as the two isomers 1- and 3-methylhistidine (1MH and 3MH), was first reported five decades ago, but remains largely unexplored. Here we report that METTL9 is a broad-specificity methyltransferase that mediates the formation of the majority of 1MH present in mouse and human proteomes. METTL9-catalyzed methylation requires a His-x-His (HxH) motif, where “x” is preferably a small amino acid, allowing METTL9 to methylate a number of HxH-containing proteins, including the immunomodulatory protein S100A9 and the NDUFB3 subunit of mitochondrial respiratory Complex I. Notably, METTL9-mediated methylation enhances respiration via Complex I, and the presence of 1MH in an HxH-containing peptide reduced its zinc binding affinity. Our results establish METTL9-mediated 1MH as a pervasive protein modification, thus setting the stage for further functional studies on protein histidine methylation.


Genetics ◽  
2002 ◽  
Vol 161 (1) ◽  
pp. 259-267 ◽  
Author(s):  
Joachim Altschmied ◽  
Jacqueline Delfgaauw ◽  
Brigitta Wilde ◽  
Jutta Duschl ◽  
Laurence Bouneau ◽  
...  

Abstract The microphthalmia-associated transcription factor (MITF) exists in at least four isoforms. These are generated in higher vertebrates using alternative 5′ exons and promoters from a single gene. Two separate genes (mitf-m and mitf-b), however, are present in different teleost fish species including the poeciliid Xiphophorus, the pufferfishes Fugu rubripes and Tetraodon nigroviridis, and the zebrafish Danio rerio. Fish proteins MITF-m and MITF-b correspond at both the structural and the expression levels to one particular bird/mammalian MITF isoform. In the teleost lineage subfunctionalization of mitf genes after duplication at least 100 million years ago is associated with the degeneration of alternative exons and, probably, regulatory elements and promoters. For example, a remnant of the first exon specific for MITF-m is detected within the pufferfish gene encoding MITF-b. Retracing the evolutionary history of mitf genes in vertebrates uncovered the differential recruitment of new introns specific for either the teleost or the bird/mammalian lineage.


2015 ◽  
Vol 24 (4) ◽  
pp. 197-205
Author(s):  
Dwi Wulandari ◽  
Lisnawati Rachmadi ◽  
Tjahjani M. Sudiro

Background: E6 and E7 are oncoproteins of HPV16. Natural amino acid variation in HPV16 E6 can alter its carcinogenic potential. The aim of this study was to analyze phylogenetically E6 and E7 genes and proteins of HPV16 from Indonesia and predict the effects of single amino acid substitution on protein function. This analysis could be used to reduce time, effort, and research cost as initial screening in selection of protein or isolates to be tested in vitro or in vivo.Methods: In this study, E6 and E7 gene sequences were obtained from 12 samples of  Indonesian isolates, which  were compared with HPV16R (prototype) and 6 standard isolates in the category of European (E), Asian (As), Asian-American (AA), African-1 (Af-1), African-2 (Af-2), and North American (NA) branch from Genbank. Bioedit v.7.0.0 was used to analyze the composition and substitution of single amino acids. Phylogenetic analysis of E6 and E7 genes and proteins was performed using Clustal X (1.81) and NJPLOT softwares. Effects of single amino acid substitutions on protein function of E6 and E7 were analysed by SNAP.Results: Java variants and isolate ui66* belonged to European branch, while the others belonged to Asian and African branches. Twelve changes of amino acids were found in E6 and one in E7 proteins. SNAP analysis showed two non neutral mutations, i.e. R10I and C63G in E6 proteins. R10I mutations were found in Af-2 genotype (AF472509) and Indonesian isolates (Af2*), while C63G mutation was found only in Af2*.Conclusion: E6 proteins of HPV16 variants were more variable than E7. SNAP analysis showed that only E6 protein of African-2 branch had functional differences compared to HPV16R.


PLoS ONE ◽  
2013 ◽  
Vol 8 (4) ◽  
pp. e59255 ◽  
Author(s):  
Mariana T. Q. de Magalhães ◽  
Eder A. Barbosa ◽  
Maura V. Prates ◽  
Rodrigo M. Verly ◽  
Victor Hugo O. Munhoz ◽  
...  

2019 ◽  
Vol 2019 (4) ◽  
Author(s):  
Khaled Al-hosaini ◽  
Stephen R. Bloom ◽  
Joseph Hedrick ◽  
Andrew Howard ◽  
Preeti Jethwa ◽  
...  

Neuromedin U receptors (provisional nomenclature as recommended by NC-IUPHAR [29]) are activated by the endogenous 25 amino acid peptide neuromedin U (neuromedin U-25, NmU-25), a peptide originally isolated from pig spinal cord [90]. In humans, NmU-25 appears to be the sole product of a precursor gene (NMU, P48645) showing a broad tissue distribution, but which is expressed at highest levels in the upper gastrointestinal tract, CNS, bone marrow and fetal liver. Much shorter versions of NmU are found in some species, but not in human, and are derived at least in some instances from the proteolytic cleavage of the longer NmU. Despite species differences in NmU structure, the C-terminal region (particularly the C-terminal pentapeptide) is highly conserved and contains biological activity. Neuromedin S (neuromedin S-33) has also been identified as an endogenous agonist [95]. NmS-33 is, as its name suggests, a 33 amino-acid product of a precursor protein derived from a single gene and contains an amidated C-terminal heptapeptide identical to NmU. NmS-33 appears to activate NMU receptors with equivalent potency to NmU-25.


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