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Jose De La Fuente - One of the best experts on this subject based on the ideXlab platform.
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The glycoprotein TRP36 of Ehrlichia sp. UFMG-EV and related cattle pathogen Ehrlichia sp. UFMT-BV evolved from a highly variable clade of E. canis under adaptive Diversifying Selection
'Springer Science and Business Media LLC', 2017Co-Authors: Cabezas-cruz Alejandro, Valdés, James J., Jose De La FuenteAbstract:[Background]: A new species of Ehrlichia, phylogenetically distant from E. ruminantium, was found in 2010 infecting cattle in Canada. In 2012 and 2013, we reported the in vitro propagation, molecular and ultrastructural characterization of Ehrlichia sp. UFMG-EV (E. mineirensis), a new species of Ehrlichia isolated from the haemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks. A new organism, named Ehrlichia sp. UFMT-BV, closely related to Ehrlichia sp. UFMG-EV, was recently described in Brazil and after experimental infection it was shown to be pathogenic for cattle. This new emerging clade of cattle Ehrlichia pathogens is closely related to E. canis. The major immunogenic Tandem Repeat Protein (TRP36; also known as gp36) is extensively used to characterize the genetic diversity of E. canis. Homologs of TRP36 were found in both Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV. [Findings]: Herein, we characterized the evolution of this new Ehrlichia clade using TRP36 sequences. Our working hypothesis is that Ehrlichia sp. UFMG-EV and related microorganisms evolved from a highly variable E. canis clade. In support of our hypothesis we found that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV TRP36 evolved from a highly divergent and variable clade within E. canis and this clade evolved under episodic Diversifying Selection with a high proportion of sites under positive Selection. [Conclusion]: Our results suggest that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV evolved from a variable clade within E. canis.This research was partially supported by the EU FP7 ANTIGONE project number 278976. JJV was sponsored by project CZ.1.07/2.3.00/30.0032, co-financed by the European Social Fund and the state budget of the Czech Republic. ACC was supported by a grant from the Ministère de l’Education Supérieure et de la Recherche of FrancePeer Reviewe
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The glycoprotein TRP36 of Ehrlichia sp. UFMG-EV and related cattle pathogen Ehrlichia sp. UFMT-BV evolved from a highly variable clade of E. canis under adaptive Diversifying Selection.
Parasites and Vectors, 2014Co-Authors: Alejandro Cabezas Cruz, James J. Valdes, Jose De La FuenteAbstract:Background: A new species of Ehrlichia, phylogenetically distant from E. ruminantium, was found in 2010 infecting cattle in Canada. In 2012 and 2013, we reported the in vitro propagation, molecular and ultrastructural characterization of Ehrlichia sp. UFMG-EV (E. mineirensis), a new species of Ehrlichia isolated from the haemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks. A new organism, named Ehrlichia sp. UFMT-BV, closely related to Ehrlichia sp. UFMG-EV, was recently described in Brazil and after experimental infection it was shown to be pathogenic for cattle. This new emerging clade of cattle Ehrlichia pathogens is closely related to E. canis. The major immunogenic Tandem Repeat Protein (TRP36; also known as gp36) is extensively used to characterize the genetic diversity of E. canis. Homologs of TRP36 were found in both Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV. Findings: Herein, we characterized the evolution of this new Ehrlichia clade using TRP36 sequences. Our working hypothesis is that Ehrlichia sp. UFMG-EV and related microorganisms evolved from a highly variable E. canis clade. In support of our hypothesis we found that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV TRP36 evolved from a highly divergent and variable clade within E. canis and this clade evolved under episodic Diversifying Selection with a high proportion of sites under positive Selection. Conclusion: Our results suggest that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV evolved from a variable clade within E. canis.
Alejandro Cabezas Cruz - One of the best experts on this subject based on the ideXlab platform.
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The glycoprotein TRP36 of Ehrlichia sp. UFMG-EV and related cattle pathogen Ehrlichia sp. UFMT-BV evolved from a highly variable clade of E. canis under adaptive Diversifying Selection.
Parasites and Vectors, 2014Co-Authors: Alejandro Cabezas Cruz, James J. Valdes, Jose De La FuenteAbstract:Background: A new species of Ehrlichia, phylogenetically distant from E. ruminantium, was found in 2010 infecting cattle in Canada. In 2012 and 2013, we reported the in vitro propagation, molecular and ultrastructural characterization of Ehrlichia sp. UFMG-EV (E. mineirensis), a new species of Ehrlichia isolated from the haemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks. A new organism, named Ehrlichia sp. UFMT-BV, closely related to Ehrlichia sp. UFMG-EV, was recently described in Brazil and after experimental infection it was shown to be pathogenic for cattle. This new emerging clade of cattle Ehrlichia pathogens is closely related to E. canis. The major immunogenic Tandem Repeat Protein (TRP36; also known as gp36) is extensively used to characterize the genetic diversity of E. canis. Homologs of TRP36 were found in both Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV. Findings: Herein, we characterized the evolution of this new Ehrlichia clade using TRP36 sequences. Our working hypothesis is that Ehrlichia sp. UFMG-EV and related microorganisms evolved from a highly variable E. canis clade. In support of our hypothesis we found that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV TRP36 evolved from a highly divergent and variable clade within E. canis and this clade evolved under episodic Diversifying Selection with a high proportion of sites under positive Selection. Conclusion: Our results suggest that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV evolved from a variable clade within E. canis.
James J. Valdes - One of the best experts on this subject based on the ideXlab platform.
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The glycoprotein TRP36 of Ehrlichia sp. UFMG-EV and related cattle pathogen Ehrlichia sp. UFMT-BV evolved from a highly variable clade of E. canis under adaptive Diversifying Selection.
Parasites and Vectors, 2014Co-Authors: Alejandro Cabezas Cruz, James J. Valdes, Jose De La FuenteAbstract:Background: A new species of Ehrlichia, phylogenetically distant from E. ruminantium, was found in 2010 infecting cattle in Canada. In 2012 and 2013, we reported the in vitro propagation, molecular and ultrastructural characterization of Ehrlichia sp. UFMG-EV (E. mineirensis), a new species of Ehrlichia isolated from the haemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks. A new organism, named Ehrlichia sp. UFMT-BV, closely related to Ehrlichia sp. UFMG-EV, was recently described in Brazil and after experimental infection it was shown to be pathogenic for cattle. This new emerging clade of cattle Ehrlichia pathogens is closely related to E. canis. The major immunogenic Tandem Repeat Protein (TRP36; also known as gp36) is extensively used to characterize the genetic diversity of E. canis. Homologs of TRP36 were found in both Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV. Findings: Herein, we characterized the evolution of this new Ehrlichia clade using TRP36 sequences. Our working hypothesis is that Ehrlichia sp. UFMG-EV and related microorganisms evolved from a highly variable E. canis clade. In support of our hypothesis we found that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV TRP36 evolved from a highly divergent and variable clade within E. canis and this clade evolved under episodic Diversifying Selection with a high proportion of sites under positive Selection. Conclusion: Our results suggest that Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT-BV evolved from a variable clade within E. canis.
Bernard Wallner - One of the best experts on this subject based on the ideXlab platform.
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Population-specific, recent positive directional Selection suggests adaptation of human male reproductive genes to different environmental conditions
BMC Evolutionary Biology, 2020Co-Authors: Helmut Schaschl, Bernard WallnerAbstract:Background Recent human transcriptomic analyses revealed a very large number of testis-enriched genes, many of which are involved in spermatogenesis. This comprehensive transcriptomic data lead us to the question whether positive Selection was a decisive force influencing the evolution and variability of testis-enriched genes in humans. We used two methodological approaches to detect different levels of positive Selection, namely episodic positive Diversifying Selection (i.e., past Selection) in the human lineage within primate phylogeny, potentially driven by sperm competition, and recent positive directional Selection in contemporary human populations, which would indicate adaptation to different environments. Results In the human lineage (after correction for multiple testing) we found that only the gene TULP2 , for which no functional data are yet available, is subject to episodic positive Diversifying Selection. Using less stringent statistical criteria (uncorrected p -values), also the gene SPATA16 , which has a pivotal role in male fertility and for which episodes of adaptive evolution have been suggested, also displays a putative signal of Diversifying Selection in the human branch. At the same time, we found evidence for recent positive directional Selection acting on several human testis-enriched genes ( MORC1 , SLC9B1 , ROPN1L , DMRT1 , PLCZ1 , RNF17 , FAM71D and WBP2NL ) that play important roles in human spermatogenesis and fertilization. Most of these genes are population-specifically under positive Selection. Conclusion Episodic Diversifying Selection, possibly driven by sperm competition, was not an important force driving the evolution of testis-enriched genes in the human lineage. Population-specific, recent positive directional Selection suggests an adaptation of male reproductive genes to different environmental conditions. Positive Selection acts on eQTLS and sQTLs, indicating selective effects on important gene regulatory functions. In particular, the transcriptional diversity regulated by sQTLs in testis-enriched genes may be important for spermatocytes to respond to environmental and physiological stress.
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Population-specific, recent positive directional Selection suggests adaptation of human male reproductive genes to different environmental conditions
BMC Evolutionary Biology, 2020Co-Authors: Helmut Schaschl, Bernard WallnerAbstract:Background Recent human transcriptomic analyses revealed a very large number of testis-enriched genes, many of which are involved in spermatogenesis. This comprehensive transcriptomic data lead us to the question whether positive Selection was a decisive force influencing the evolution and variability of testis-enriched genes in humans. We used two methodological approaches to detect different levels of positive Selection, namely episodic positive Diversifying Selection (i.e., past Selection) in the human lineage within primate phylogeny, potentially driven by sperm competition, and recent positive directional Selection in contemporary human populations, which would indicate adaptation to different environments. Results In the human lineage (after correction for multiple testing) we found that only the gene TULP2 , for which no functional data are yet available, is subject to episodic positive Diversifying Selection. Using less stringent statistical criteria (uncorrected p -values), also the gene SPATA16 , which has a pivotal role in male fertility and for which episodes of adaptive evolution have been suggested, also displays a putative signal of Diversifying Selection in the human branch. At the same time, we found evidence for recent positive directional Selection acting on several human testis-enriched genes ( MORC1 , SLC9B1 , ROPN1L , DMRT1 , PLCZ1 , RNF17 , FAM71D and WBP2NL ) that play important roles in human spermatogenesis and fertilization. Most of these genes are population-specifically under positive Selection. Conclusion Episodic Diversifying Selection, possibly driven by sperm competition, was not an important force driving the evolution of testis-enriched genes in the human lineage. Population-specific, recent positive directional Selection suggests an adaptation of male reproductive genes to different environmental conditions. Positive Selection acts on eQTLS and sQTLs, indicating selective effects on important gene regulatory functions. In particular, the transcriptional diversity regulated by sQTLs in testis-enriched genes may be important for spermatocytes to respond to environmental and physiological stress.
Osamu Kaneko - One of the best experts on this subject based on the ideXlab platform.
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Positive Diversifying Selection on the Plasmodium falciparum surf4.1 gene in Thailand.
Tropical medicine and health, 2012Co-Authors: Phonepadith Xangsayarath, Morakot Kaewthamasorn, Kazuhide Yahata, Shusuke Nakazawa, Jetsumon Sattabongkot, Rachanee Udomsangpetch, Osamu KanekoAbstract:Plasmodium falciparum SURFIN4.1 is a type I transmembrane protein thought to locate on the merozoite surface and to be responsible for a reversible adherence to the erythrocyte before invasion. In this study, we evaluated surf4.1 gene segment encoding extracellular region for polymorphism, the signature of positive Selection, the degree of linkage disequilibrium, and temporal change in allele frequency distribution in P. falciparum isolates from Thailand in 1988–89, 2003, and 2005. We found that SURFIN4.1 is highly polymorphic, particularly at the C-terminal side of the variable region located just before a predicted transmembrane region. A signature of positive Diversifying Selection on the variable region was detected by multiple tests and, to a lesser extent, on conserved N-terminally located cysteine-rich domain by Tajima’s D test. Linkage disequilibrium between sites over a long distance (> 1.5 kb) was detected, and multiple SURFIN4.1 haplotype sequences detected in 1988/89 still circulated in 2003. Few of the single amino acid polymorphism allele frequency distributions were significantly different between the 1988/89 and 2003 groups, suggesting that the frequency distribution of SURFIN4.1 extracellular region remained stable over 14 years.
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Positive Diversifying Selection on Plasmodium vivax RON2 protein.
Parasitology, 2012Co-Authors: Jianxia Tang, Yang Dai, Hongwei Zhang, Richard Culleton, Yaobo Liu, Song Zhao, Xiaoting Wang, Xiaohong Guan, Osamu Kaneko, Yinchang ZhuAbstract:Plasmodium rhoptry neck protein 2 (RON2), which is released from the neck portion of the merozoite rhoptries and interacts with the microneme protein Apical Membrane Antigen 1 (AMA1), plays a crucial role in erythrocyte invasion. In this study, we sequenced the Plasmodium vivax RON2 gene from 19 P. vivax isolates collected in central China in order to establish whether this protein is under positive Diversifying Selection, which may occur as a result of protective host immune pressure†. In comparison with the P. vivax Sal-1 reference line, we found 10 amino acid substitutions dispersed throughout the open reading frame as well as indels caused by polymorphism in a repeat unit (21-23 repeats of (Q/E/K/N/H)(G/D)G(H/L/Y/P)G) in the second tandem repeat region located at amino acid positions 541-650. A McDonald-Kreitman test with RON2 sequences from the primate malaria parasite Plasmodium knowlesi, detected significant departure from neutrality in the PvRON2 3' region (nucleotide positions 2668-6609). These results suggest that the PvRON2 gene has evolved under positive Diversifying Selection.