Search results for "Synonym"
showing 10 items of 101 documents
NATURAL SELECTION AND THE ORGAN-SPECIFIC DIFFERENTIATION OF HIV-1 V3 HYPERVARIABLE REGION
2004
The existence of organ-specific HIV-1 populations within infected hosts has been studied for many years; nonetheless results reported by different authors are somewhat discrepant. To tackle this problem, we used a population genetics approach to analyze previously published data from the V3 hypervariable region of the envelope env gene. Our results are compatible with a population subdivision by organs in 95% of individuals analyzed at autopsy. In addition, populations infecting the nervous system and testicles clearly appear as differentiated subsets of the so-called macrophage-tropic variants. Liver and kidney may harbor differentiated populations as well. Although it is widely accepted t…
Genetic variability and evolutionary analysis of parietaria mottle virus: role of selection and genetic exchange
2015
[EN] The genetic variability and evolution of parietaria mottle virus (PMoV) of the genus Ilarvirus was studied by analyzing nucleotide sequences of 2b and CP genes from isolates collected in different countries. Phylogenetic analysis showed that PMoV isolates clustered in different clades: one (clade I) composed of only Italian isolates and three clades (clades II-IV) including the Spanish isolates. The Greek isolate GrT-1 used in this study was in clade IV for the CP phylogenetic tree whereas it formed a separate branch in the 2b phylogenetic tree. The nucleotide sequence diversity of both the 2b and CP genes was low (0.062 +/- A 0.006 and 0.063 +/- A 0.006 for 2b and CP, respectively) bu…
Comparative Sequence Analysis ofMycobacterium lepraeand the New Leprosy-CausingMycobacterium lepromatosis
2009
ABSTRACTMycobacterium lepromatosisis a newly discovered leprosy-causing organism. Preliminary phylogenetic analysis of its 16S rRNA gene and a few other gene segments revealed significant divergence fromMycobacterium leprae, a well-known cause of leprosy, that justifies the status ofM. lepromatosisas a new species. In this study we analyzed the sequences of 20 genes and pseudogenes (22,814 nucleotides). Overall, the level of matching of these sequences withM. lepraesequences was 90.9%, which substantiated the species-level difference; the levels of matching for the 16S rRNA genes and 14 protein-encoding genes were 98.0% and 93.1%, respectively, but the level of matching for five pseudogenes…
Taxas de substituições das Annonaceas: uma perspectiva do modelo códon
2014
The Annonaceae includes cultivated species of economic interest and represents an important source of information for better understanding the evolution of tropical rainforests. In phylogenetic analyses of DNA sequence data that are used to address evolutionary questions, it is imperative to use appropriate statistical models. Annonaceae are cases in point: Two sister clades, the subfamilies Annonoideae and Malmeoideae, contain the majority of Annonaceae species diversity. The Annonoideae generally show a greater degree of sequence divergence compared to the Malmeoideae, resulting in stark differences in branch lengths in phylogenetic trees. Uncertainty in how to interpret and analyse these…
The fitness effects of synonymous mutations in DNA and RNA viruses.
2011
Despite being silent with respect to protein sequence, synonymous nucleotide substitutions can be targeted by natural selection directly at the DNA or RNA level. However, there has been no systematic assessment of how frequent this type of selection is. Here, we have constructed 53 single random synonymous substitution mutants of the bacteriophages Qb and UX174 by site-directed mutagenesis and assayed their fitness. Analysis of this mutant collection and of previous studies undertaken with a variety of single-stranded (ss) viruses demonstrates that selection at synonymous sites is stronger in RNA viruses than in DNA viruses. We estimate that this type of selection contributes approximately …
Revision of the European, North-African and Central Asian species of the genus Norbanus Walker 1843 (Hymenoptera: Pteromalidae)
2010
The European, North-African and Central Asian species of the genus Norbanus Walker are revised, providing an illustrated key to males and females of all the species. Three new synonymies are proposed: Norbanus globulariae (Szele´nyi 1941) 5 Norbanus giordanii (Ferrie`re 1952), n. syn.; Norbanus meridionalis (Masi 1922) 5 Norbanus mordellidarum Dzhanokmen 1999, n. syn.; Norbanus obscurus (Masi 1922) 5 Norbanus erdoesi (Szele´nyi 1974), n. syn. Both sexes of N. guyoni are redescribed, and its type locality clarified. A new host record together with distributional data are given for nine out of ten valid species.
A new subspecies of Epipactis microphylla (Orchidaceae; Epidendroideae) from Pantelleria Island (Sicily)
2021
A new subspecies of Epipactis microphylla, proposed as subsp. cossyrensis is described and illustrated from Pantelleria, a volcanic island near Sicily. It differs from subsp. microphylla mainly in the shape and size of leaves and bracts and several floral traits. This taxon, previously attributed to E. pollinensis, a species currently treated as a synonym of E. purpurata, grows in the undergrowth of thermophilous woodlands occurring on the top of the island, where it numbers a few tens of individuals. The conservation status, phenology and taxonomic remarks are provided. Keys for the species belonging to the Epipactis atrorubens group (= subsect. Atrorubensae), including E. microphylla, are…
Clinical aspects of painful conditions
2017
Sudeck’s atrophy, also known by the synonym “reflex sympathetic dystrophy,” is now described by the term “complex regional pain syndrome” (CRPS). This umbrella term has been subdivided into type I and type II.
Mutagenesis scanning uncovers evolutionary constraints on tobacco etch Potyvirus membrane-associated 6K2 protein
2019
RNA virus high mutation rate is a double-edged sword. At the one side, most mutations jeopardize proteins functions; at the other side, mutations are needed to fuel adaptation. The relevant question then is the ratio between beneficial and deleterious mutations. To evaluate this ratio, we created a mutant library of the 6K2 gene of tobacco etch potyvirus that contains every possible single-nucleotide substitution. 6K2 protein anchors the virus replication complex to the network of endoplasmic reticulum membranes. The library was inoculated into the natural host Nicotiana tabacum, allowing competition among all these mutants and selection of those that are potentially viable. We identified 1…
Widespread selection for high and low secondary structure in coding sequences across all domains of life
2019
AbstractCodon composition, GC-content and local RNA secondary structures can have a profound effect on gene expression and mutations affecting these parameters, even though they do not alter the protein sequence, are not neutral in terms of selection. Although evidence exists that in some cases selection favors more stable RNA secondary structures, we currently lack a concrete idea of how many genes are affected within a species, and if this is a universal phenomenon in nature.We searched for signs of structural selection in a global manner, analyzing a set of one million coding sequences from 73 species representing all domains of life, as well as viruses, by means of our newly developed s…