giganteus. Phylogenetic analyses based on protein-coding genes recovered Hydroides as a monophyletic group sister to Spirobranchus with a long branch, and sister to the fan worm Sabellidae. Yet the Serpulidae + Sabellidae clade was unexpectedly grouped with Sipuncula, suggesting that mitochondrial genomes alone are insufficient to resolve the phylogenetic position of Serpulidae within Annelida due to its high base substitution rates. Overall, our study revealed a high variability in the gene order arrangement of mitochondrial genomes within Serpulidae, provided evidence to question the conserved pattern of the mitochondrial gene order in Annelida and called for caution when applying mitochondrial genes to infer their phylogenetic relationships.We evaluated the role of Quaternary climatic fluctuations on the demographic history and population structure of amphibian species endemic to the 'campo rupestre' in the Neotropics, evaluating their distributional shifts, demographic changes, and lineage formation from the end of Pleistocene to present. We chose two anurans endemic to the high-elevation 'campo rupestre' in the Espinhaço Range (ER) in northeastern and southeastern Brazil (Bokermannohyla alvarengai and Bokermannohyla oxente), as models to test the role of Quaternary climatic fluctuations over their distribution range in this region. We collected tissue samples throughout their distribution range and used statistical phylogeography to examine processes of divergence and population demography. We generated spatial-temporal reconstructions using Bayesian inference in a coalescent framework in combination with hind-cast projections of species distribution models (SDMs). We also used the results and literature information to test alternative diversiation gradients in tropical and subtropical domains. Such processes may influence the evolution of the biota distributed in heterogeneous landscapes with varied topography.Some tropical plant families, such as the Sapotaceae, have a complex taxonomy, which can be resolved using Next Generation Sequencing (NGS). For most groups however, methodological protocols are still missing. Here we identified 531 monocopy genes and 227 Short Tandem Repeats (STR) markers and tested them on Sapotaceae using target capture and NGS. The probes were designed using two genome skimming samples from Capurodendron delphinense and Bemangidia lowryi, both from the Tseboneae tribe, as well as the published Manilkara zapota transcriptome from the Sapotoideae tribe. We combined our probes with 261 additional ones previously published and designed for the entire angiosperm group. On a total of 792 low-copy genes, 638 showed no signs of paralogy and were used to build a phylogeny of the family with 231 individuals from all main lineages. A highly supported topology was obtained at high taxonomic ranks but also at the species level. https://www.selleckchem.com/products/3-methyladenine.html This phylogeny revealed the existence of more than 20 putative new species. Single nucleotide polymorphisms (SNPs) extracted from the 638 genes were able to distinguish lineages within a species complex and to highlight geographical structuration. STR were recovered efficiently for the species used as reference (C. delphinense) but the recovery rate decreased dramatically with the phylogenetic distance to the focal species. Altogether, the new loci will help reaching a sound taxonomic understanding of the family Sapotaceae for which many circumscriptions and relationships are still debated, at the species, genus and tribe levels.The molluscan class Gastropoda includes over 5,000 parasitic species whose evolutionary origins remain poorly understood. Marine snails of the genus Caledoniella (Caledoniellidae) are obligate parasites that live on the abdominal surface of the gonodactylid mantis shrimps. They have highly modified morphological characteristics specialized to the ectoparasitic lifestyle that make it difficult to infer their close relatives, thereby posing a question about their current systematic position in the superfamily Vanikoroidea. In the present study, we performed molecular phylogenetic analyses using three nuclear and three mitochondrial gene sequences to unveil the phylogenetic position of these enigmatic snails. The resulting trees recovered Caledoniella in the superfamily Truncatelloidea and within a subclade of commensal species that live on the burrow wall of marine benthic invertebrates. More specifically, Caledoniella formed the sister clade to a commensal snail species living in mantis-shrimp burrows and they collectively were sister to Sigaretornus planus (formerly in the family Tornidae or Vitrinellidae), a commensal living in echiuran burrows. This topology suggests that the species of Caledoniella achieved their ectoparasitic mode of life through the following evolutionary pathway (1) invasion into the burrows of benthic invertebrates, (2) specialization to mantis shrimps, and (3) colonization of the host body surface from the host burrow wall with the evolution of the parasitic nature. The final step is likely to have been accompanied by the acquisition of a sucker on the metapodium, the loss of the radula and operculum, and the formation of monogamous pair bonds. The present molecular phylogeny also suggested parallel evolution of planispiral shells in a subclade of Truncatelloidea and enabled us to newly redefine the families Caledoniellidae, Elachisinidae, Teinostomatidae, Tornidae and Vitrinellidae.Hematopoietic stem cell (HSC) heterogeneity and hierarchy are a current topic of interest, having major implications for clinical HSC transplantation and basic research on human HSCs. It was long believed that the most primitive HSCs in mammals, including **** and humans, were CD34 antigen positive (CD34+). However, 2 decades ago, it was reported that murine long-term multilineage reconstituting HSCs were lineage marker negative (Lin-, i.e., c-kit+Sca-1+CD34low/-), known as CD34low/- KSL cells. In contrast, human CD34- HSCs, a counterpart of murine CD34low/- KSL cells, were hard to identify for a long time mainly because of their rarity. We previously identified very primitive human cord blood (CB)-derived CD34- severe combined immunodeficiency (SCID)-repopulating cells (SRCs) using the intra-bone marrow injection method and proposed the new concept that CD34- SRCs (HSCs) reside at the apex of the human HSC hierarchy. Through a series of studies, we identified two positive/enrichment markers CD133 and GPI-80.
giganteus. Phylogenetic analyses based on protein-coding genes recovered Hydroides as a monophyletic group sister to Spirobranchus with a long branch, and sister to the fan worm Sabellidae. Yet the Serpulidae + Sabellidae clade was unexpectedly grouped with Sipuncula, suggesting that mitochondrial genomes alone are insufficient to resolve the phylogenetic position of Serpulidae within Annelida due to its high base substitution rates. Overall, our study revealed a high variability in the gene order arrangement of mitochondrial genomes within Serpulidae, provided evidence to question the conserved pattern of the mitochondrial gene order in Annelida and called for caution when applying mitochondrial genes to infer their phylogenetic relationships.We evaluated the role of Quaternary climatic fluctuations on the demographic history and population structure of amphibian species endemic to the 'campo rupestre' in the Neotropics, evaluating their distributional shifts, demographic changes, and lineage formation from the end of Pleistocene to present. We chose two anurans endemic to the high-elevation 'campo rupestre' in the Espinhaço Range (ER) in northeastern and southeastern Brazil (Bokermannohyla alvarengai and Bokermannohyla oxente), as models to test the role of Quaternary climatic fluctuations over their distribution range in this region. We collected tissue samples throughout their distribution range and used statistical phylogeography to examine processes of divergence and population demography. We generated spatial-temporal reconstructions using Bayesian inference in a coalescent framework in combination with hind-cast projections of species distribution models (SDMs). We also used the results and literature information to test alternative diversiation gradients in tropical and subtropical domains. Such processes may influence the evolution of the biota distributed in heterogeneous landscapes with varied topography.Some tropical plant families, such as the Sapotaceae, have a complex taxonomy, which can be resolved using Next Generation Sequencing (NGS). For most groups however, methodological protocols are still missing. Here we identified 531 monocopy genes and 227 Short Tandem Repeats (STR) markers and tested them on Sapotaceae using target capture and NGS. The probes were designed using two genome skimming samples from Capurodendron delphinense and Bemangidia lowryi, both from the Tseboneae tribe, as well as the published Manilkara zapota transcriptome from the Sapotoideae tribe. We combined our probes with 261 additional ones previously published and designed for the entire angiosperm group. On a total of 792 low-copy genes, 638 showed no signs of paralogy and were used to build a phylogeny of the family with 231 individuals from all main lineages. A highly supported topology was obtained at high taxonomic ranks but also at the species level. https://www.selleckchem.com/products/3-methyladenine.html This phylogeny revealed the existence of more than 20 putative new species. Single nucleotide polymorphisms (SNPs) extracted from the 638 genes were able to distinguish lineages within a species complex and to highlight geographical structuration. STR were recovered efficiently for the species used as reference (C. delphinense) but the recovery rate decreased dramatically with the phylogenetic distance to the focal species. Altogether, the new loci will help reaching a sound taxonomic understanding of the family Sapotaceae for which many circumscriptions and relationships are still debated, at the species, genus and tribe levels.The molluscan class Gastropoda includes over 5,000 parasitic species whose evolutionary origins remain poorly understood. Marine snails of the genus Caledoniella (Caledoniellidae) are obligate parasites that live on the abdominal surface of the gonodactylid mantis shrimps. They have highly modified morphological characteristics specialized to the ectoparasitic lifestyle that make it difficult to infer their close relatives, thereby posing a question about their current systematic position in the superfamily Vanikoroidea. In the present study, we performed molecular phylogenetic analyses using three nuclear and three mitochondrial gene sequences to unveil the phylogenetic position of these enigmatic snails. The resulting trees recovered Caledoniella in the superfamily Truncatelloidea and within a subclade of commensal species that live on the burrow wall of marine benthic invertebrates. More specifically, Caledoniella formed the sister clade to a commensal snail species living in mantis-shrimp burrows and they collectively were sister to Sigaretornus planus (formerly in the family Tornidae or Vitrinellidae), a commensal living in echiuran burrows. This topology suggests that the species of Caledoniella achieved their ectoparasitic mode of life through the following evolutionary pathway (1) invasion into the burrows of benthic invertebrates, (2) specialization to mantis shrimps, and (3) colonization of the host body surface from the host burrow wall with the evolution of the parasitic nature. The final step is likely to have been accompanied by the acquisition of a sucker on the metapodium, the loss of the radula and operculum, and the formation of monogamous pair bonds. The present molecular phylogeny also suggested parallel evolution of planispiral shells in a subclade of Truncatelloidea and enabled us to newly redefine the families Caledoniellidae, Elachisinidae, Teinostomatidae, Tornidae and Vitrinellidae.Hematopoietic stem cell (HSC) heterogeneity and hierarchy are a current topic of interest, having major implications for clinical HSC transplantation and basic research on human HSCs. It was long believed that the most primitive HSCs in mammals, including mice and humans, were CD34 antigen positive (CD34+). However, 2 decades ago, it was reported that murine long-term multilineage reconstituting HSCs were lineage marker negative (Lin-, i.e., c-kit+Sca-1+CD34low/-), known as CD34low/- KSL cells. In contrast, human CD34- HSCs, a counterpart of murine CD34low/- KSL cells, were hard to identify for a long time mainly because of their rarity. We previously identified very primitive human cord blood (CB)-derived CD34- severe combined immunodeficiency (SCID)-repopulating cells (SRCs) using the intra-bone marrow injection method and proposed the new concept that CD34- SRCs (HSCs) reside at the apex of the human HSC hierarchy. Through a series of studies, we identified two positive/enrichment markers CD133 and GPI-80.
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