101 research outputs found
Renewed diversification following Miocene landscape turnover in a Neotropical butterfly radiation
International audienceAim: The landscape of the Neotropical region has undergone dynamic evolution throughout the Miocene, with the extensive Pebas wetland occupying western Amazonia between 23 and c. 10 Ma and the continuous uplift of the Andes mountains. The complex interaction between the Andes and Amazonia probably influenced the trajectory of Neotropical biodiversity, but evidence from timeâcalibrated phylogenies of groups that diversified during this period is lacking. We investigate the role of these landscape transformations in the dynamics of diversification in the Neotropical region using a 26âMyrâold endemic butterfly radiation.Location: Neotropics.Time period: Oligocene to present.Major taxa studied: Ithomiini butterflies.Methods: We generated one of the most comprehensive timeâcalibrated molecular phylogenies of a large clade of Neotropical insects, the butterfly tribe Ithomiini, comprising 340 species (87% of extant species) and spanning 26 Myr of diversification. We applied a large array of birthâdeath models and historical biogeography estimations to assess the dynamics of diversification and biotic interchanges, especially at the AmazoniaâAndes interface.Results: Our results suggest that the Amazonian Pebas wetland system played a major role in the timing and geography of diversification of Ithomiini, by constraining dispersal and diversification in the Amazon basin until c. 10 Ma. During the Pebas wetland period, Ithomiini diversification mostly took place in the Andes, where terrestrial habitats were not affected. An explosion of interchanges with Amazonia and with the Northern Andes accompanied the demise of the Pebas system (11â8 Ma) and was followed by local diversification in those areas, which led to a substantial renewal of diversification.Main conclusions: Many studies on Neotropical diversity have focused only on the Andes, whereas we show that it is the waxing and waning of the Pebas megaâwetland, interacting with Andean uplift, that determined the timing and patterns of regional interchanges and diversification in Ithomiini
Genus Paracoccidioides: Species Recognition and Biogeographic Aspects
Background: Paracoccidioidomycosis is a systemic mycosis caused by Paracoccidioides brasiliensis (species S1, PS2, PS3), and Paracoccidioides lutzii. This work aimed to differentiate species within the genus Paracoccidioides, without applying multilocus sequencing, as well as to obtain knowledge of the possible speciation processes. Methodology/Principal Findings:
Single nucleotide polymorphism analysis on GP43, ARF and PRP8 intein genes successfully distinguished isolates into four different species. Morphological evaluation indicated that elongated conidia were observed exclusively in P. lutzii isolates, while all other species (S1, PS2 and PS3) were indistinguishable. To evaluate the biogeographic events that led to the current geographic distribution of Paracoccidioides species and their sister species, Nested Clade and Likelihood Analysis of Geographic Range Evolution (LAGRANGE) analyses were applied. The radiation of Paracoccidioides started in northwest South America, around 11â32 million years ago, as calculated on the basis of ARF substitution rate, in the BEAST program. Vicariance was responsible for the divergence among S1, PS2 and P. lutzii and a recent dispersal generated the PS3 species, restricted to Colombia. Taking into account the ancestral areas revealed by the LAGRANGE analysis and the major geographic distribution of L. loboi in the Amazon basin, a region strongly affected by the Andes uplift and marine incursions in the Cenozoic era, we also speculate about the effect of these geological events on the vicariance between Paracoccidioides and L. loboi. Conclusions/Significance: The use of at least 3 SNPs, but not morphological criteria, as markers allows us to distinguish among the four cryptic species of the genus Paracoccidioides. The work also presents a biogeographic study speculating on how these species might have diverged in South America, thus contributing to elucidating evolutionary aspects of the genus Paracoccidioides
Phylogenetic Analysis of Seven WRKY Genes across the Palm Subtribe Attaleinae (Arecaceae) Identifies Syagrus as Sister Group of the Coconut
BACKGROUND:The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera L., the coconut, the origins of which have been one of the "abominable mysteries" of palm systematics for decades. Previous studies with predominantly plastid genes weakly supported American ancestry for the coconut but ambiguous sister relationships. In this paper, we use multiple single copy nuclear loci to address the phylogeny of the Cocoseae subtribe Attaleinae, and resolve the closest extant relative of the coconut. METHODOLOGY/PRINCIPAL FINDINGS:We present the results of combined analysis of DNA sequences of seven WRKY transcription factor loci across 72 samples of Arecaceae tribe Cocoseae subtribe Attaleinae, representing all genera classified within the subtribe, and three outgroup taxa with maximum parsimony, maximum likelihood, and Bayesian approaches, producing highly congruent and well-resolved trees that robustly identify the genus Syagrus as sister to Cocos and resolve novel and well-supported relationships among the other genera of the Attaleinae. We also address incongruence among the gene trees with gene tree reconciliation analysis, and assign estimated ages to the nodes of our tree. CONCLUSIONS/SIGNIFICANCE:This study represents the as yet most extensive phylogenetic analyses of Cocoseae subtribe Attaleinae. We present a well-resolved and supported phylogeny of the subtribe that robustly indicates a sister relationship between Cocos and Syagrus. This is not only of biogeographic interest, but will also open fruitful avenues of inquiry regarding evolution of functional genes useful for crop improvement. Establishment of two major clades of American Attaleinae occurred in the Oligocene (ca. 37 MYBP) in Eastern Brazil. The divergence of Cocos from Syagrus is estimated at 35 MYBP. The biogeographic and morphological congruence that we see for clades resolved in the Attaleinae suggests that WRKY loci are informative markers for investigating the phylogenetic relationships of the palm family
ĐĐ”ŃĐŸĐŽ ĐžĐœŃДгŃĐžŃĐŸĐČĐ°ĐœĐžŃ ĐŽĐžŃŃĐ”ŃĐ”ĐœŃОалŃĐœŃŃ ŃŃĐ°ĐČĐœĐ”ĐœĐžĐč ĐŽĐžĐœĐ°ĐŒĐžĐșĐž ŃлДĐșŃŃĐžŃĐ”ŃĐșĐžŃ ĐŒĐ°ŃĐžĐœ Ń ĐČŃĐ°ŃĐ°ŃŃĐžĐŒŃŃ ŃĐŸŃĐŸŃĐŸĐŒ
ĐĐ»Ń ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžŃ ĐżĐ”ŃĐ”Ń
ĐŸĐŽĐœŃŃ
ĐżŃĐŸŃĐ”ŃŃĐŸĐČ ĐČ ŃлДĐșŃŃĐŸŃĐ”Ń
ĐœĐžŃĐ”ŃĐșĐžŃ
ŃĐžŃŃĐ”ĐŒĐ°Ń
, ŃĐŸĐŽĐ”ŃжаŃĐžŃ
ŃŃĐ°ŃĐžŃĐ”ŃĐșОД ŃлДĐșŃŃĐŸĐŒĐ°ĐłĐœĐžŃĐœŃĐ” ŃŃŃŃĐŸĐčŃŃĐČĐ°, ĐČĐșĐ»ŃŃĐ”ĐœĐœŃĐ” ĐČ ŃĐ»ĐŸĐ¶ĐœŃĐ” ŃлДĐșŃŃĐžŃĐ”ŃĐșОД ŃŃ
Đ”ĐŒŃ, ŃĐ°Đ·ŃĐ°Đ±ĐŸŃĐ°Đœ ĐżŃĐŸĐłŃĐ°ĐŒĐŒĐœŃĐč ĐșĐŸĐŒĐżĐ»Đ”ĐșŃ Colo, ŃŃĐœĐșŃĐžĐŸĐœĐžŃŃŃŃĐžĐč ĐœĐ° ĐŸŃĐœĐŸĐČĐ” ĐŒĐ°ĐłĐœĐžŃĐŸŃлДĐșŃŃĐžŃĐ”ŃĐșĐžŃ
ŃŃ
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ОлО ĐŒĐ°ĐłĐœĐžŃĐœŃŃ
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. ĐĐŸĐŽĐ”Đ»ĐžŃĐŸĐČĐ°ĐœĐžĐ” ĐŽĐžĐœĐ°ĐŒĐžŃĐ”ŃĐșĐžŃ
ĐżŃĐŸŃĐ”ŃŃĐŸĐČ ĐČ ŃлДĐșŃŃĐžŃĐ”ŃĐșĐžŃ
ĐŒĐ°ŃĐžĐœĐ°Ń
Ń ĐČŃĐ°ŃĐ°ŃŃĐžĐŒŃŃ ŃĐŸŃĐŸŃĐŸĐŒ ŃĐČŃĐ·Đ°ĐœĐŸ Ń ĐžĐœŃДгŃĐžŃĐŸĐČĐ°ĐœĐžĐ”ĐŒ ĐŽĐžŃŃĐ”ŃĐ”ĐœŃОалŃĐœŃŃ
ŃŃĐ°ĐČĐœĐ”ĐœĐžĐč, ĐČ ĐșĐŸŃĐŸŃŃĐ” ĐČŃ
ĐŸĐŽŃŃ ĐżŃĐŸĐžĐ·ĐČĐ”ĐŽĐ”ĐœĐžŃ ĐžŃĐșĐŸĐŒŃŃ
ĐČДлОŃĐžĐœ, ĐżĐŸŃŃĐŸĐŒŃ ĐœĐ”ĐżĐŸŃŃДЎŃŃĐČĐ”ĐœĐœĐŸ ŃŃĐž ŃŃĐ°ĐČĐœĐ”ĐœĐžŃ ĐœĐ” ĐŒĐŸĐłŃŃ ŃĐ”ŃĐ°ŃŃŃŃ ĐČ ĐżŃĐŸĐłŃĐ°ĐŒĐŒĐœĐŸĐŒ ĐșĐŸĐŒĐżĐ»Đ”ĐșŃĐ” Colo
The macrophage in HIV-1 infection: From activation to deactivation?
Macrophages play a crucial role in innate and adaptative immunity in response to microorganisms and are an important cellular target during HIV-1 infection. Recently, the heterogeneity of the macrophage population has been highlighted. Classically activated or type 1 macrophages (M1) induced in particular by IFN-Îł display a pro-inflammatory profile. The alternatively activated or type 2 macrophages (M2) induced by Th-2 cytokines, such as IL-4 and IL-13 express anti-inflammatory and tissue repair properties. Finally IL-10 has been described as the prototypic cytokine involved in the deactivation of macrophages (dM). Since the capacity of macrophages to support productive HIV-1 infection is known to be modulated by cytokines, this review shows how modulation of macrophage activation by cytokines impacts the capacity to support productive HIV-1 infection. Based on the activation status of macrophages we propose a model starting with M1 classically activated macrophages with accelerated formation of viral reservoirs in a context of Th1 and proinflammatory cytokines. Then IL-4/IL-13 alternatively activated M2 macrophages will enter into the game that will stop the expansion of the HIV-1 reservoir. Finally IL-10 deactivation of macrophages will lead to immune failure observed at the very late stages of the HIV-1 disease
Recommended from our members
Track A Basic Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138319/1/jia218438.pd
Pollinator-flower interactions in gardens during the COVID-19 pandemic lockdown of 2020
During the main COVID-19 global pandemic lockdown period of 2020 an impromptu set of pollination ecologists came together via social media and personal contacts to carry out standardised surveys of the flower visits and plants in gardens. The surveys involved 67 rural, suburban and urban gardens, of various sizes, ranging from 61.18° North in Norway to 37.96° South in Australia, resulting in a data set of 25,174 rows, with each row being a unique interaction record for that date/site/plant species, and comprising almost 47,000 visits to flowers, as well as records of flowers that were not visited by pollinators, for over 1,000 species and varieties belonging to more than 460genera and 96plant families. The more than 650 species of flower visitors belong to 12 orders of invertebrates and four of vertebrates. In this first publication from the project, we present a brief description of the data and make it freely available for any researchers to use in the future, the only restriction being that they cite this paper in the first instance. The data generated from these global surveys will provide scientific evidence to help us understand the role that private gardens (in urban, rural and suburban areas) can play in conserving insect pollinators and identify management actions to enhance their potential
Reconciling the stratigraphy and depositional history of the Lycian orogen-top basins, SW Anatolia
Terrestrial fossil records from the SWAnatolian basins are crucial both for regional correlations and palaeoenvironmental reconstructions.
By reassessing biostratigraphic constraints and incorporating new fossil data, we calibrated and reconstructed the late Neogene
andQuaternary palaeoenvironments within a regional palaeogeographical framework. The culmination of the Taurides inSWAnatolia
was followed by a regional crustal extension from the late Tortonian onwards that created a broad array of NE-trending orogen-top
basins with synchronic associations of alluvial fan, fluvial and lacustrine deposits. The terrestrial basins are superimposed on the upper
Burdigalian marine units with a c. 7 myr of hiatus that corresponds to a shift from regional shortening to extension. The initial infill of
these basins is documented by a transition from marginal alluvial fans and axial fluvial systems into central shallow-perennial lakes
coinciding with a climatic shift from warm/humid to arid conditions. The basal alluvial fan deposits abound in fossil macro-mammals
of an early Turolian (MN11â12; late Tortonian) age. The Pliocene epoch in the region was punctuated by subhumid/humid conditions
resulting in a rise of local base levels and expansion of lakes as evidenced by marsh-swamp deposits containing diverse fossilmammal
assemblages indicating late Ruscinian (lateMN15; late Zanclean) ageWe are grateful for the support of the international
bilateral project between The Scientific and Technological Research
Council of Turkey (TUBITAK) and The Russian Scientific Foundation
(RFBR) with grant a number of 111Y192. M.C.A. is grateful to the
Turkish Academy of Sciences (TUBA) for a GEBIP (Young Scientist
Award) grant. T.K. and S.M. are grateful to the Ege University
Scientific Research Center for the TTM/002/2016 and TTM/001/2016
projects. M.C.A., H.A., S.M. and M.B. have obtained Martin and
Temmick Fellowships at Naturalis Biodiversity Center (Leiden). F.A.D.
is supported by a Mehmet Akif Ersoy University Scientific Research
Grant. T.A.N. is supported by an Alexander-von-Humboldt
Scholarship. L.H.O. received support from TUBITAK under the 2221
program for visiting scientists
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