Search results for "Lineage"
showing 10 items of 331 documents
Brachyodonty and hypsodontyin some Palaeogene Eurasiatic Lagomorphs
1977
Abstract Palaeogene Eurasiatic lagomorphs show more or less different degrees and kinds of brachiodonty and hypsodonty in the cheek teeth. No fully brachyodont lagomorphs are known up to the present. The probably Paleocene Mimolagus from Western Kansu shows the less advanced stage against partial hypsodonty in the upper cheek teeth. Partial hypsodonty is more advanced in the late Eocene Mongolian genera Shamolagus, Gobiolagus and Lushilagus. Roots, however, are still well developed in the cheek teeth. Some recent discoveries from earlier Oligocene sites in France and Germany seem to represent a comparable degree of hypsodonty. The Asiatic Oligocene Desmatolagus is partiallyhypsodont with ro…
Heterogeneity and temporal dynamics of evolution of G1 human rotaviruses in a settled population.
2006
ABSTRACT A rotavirus sample collection from 19 consecutive years was used to investigate the heterogeneity and the dynamics of evolution of G1 rotavirus strains in a geographically defined population. Phylogenetic analysis of the VP7 gene sequences of G1P[8] human rotavirus strains showed the circulation of a heterogeneous population comprising three lineages and seven sublineages. Increases in the circulation of G1 rotaviruses were apparently associated with the introduction of novel G1 strains that exhibited multiple amino acid changes in antigenic regions involved in rotavirus neutralization compared to the strains circulating in the previous years. The emergence and/or introduction of G…
Generation of T Follicular Helper Cells Is Mediated by Interleukin-21 but Independent of T Helper 1, 2, or 17 Cell Lineages
2008
After activation, CD4(+) helper T (Th) cells differentiate into distinct effector subsets. Although chemokine (C-X-C motif) receptor 5-expressing T follicular helper (Tfh) cells are important in humoral immunity, their developmental regulation is unclear. Here we show that Tfh cells had a distinct gene expression profile and developed in vivo independently of the Th1 or Th2 cell lineages. Tfh cell generation was regulated by ICOS ligand (ICOSL) expressed on B cells and was dependent on interleukin-21 (IL-21), IL-6, and signal transducer and activator of transcription 3 (STAT3). However, unlike Th17 cells, differentiation of Tfh cells did not require transforming growth factor beta (TGF-beta…
On the hybrid origin of the C2Salsola divaricata agg. (Amaranthaceae) from C3 and C4 parental lineages
2021
AbstractC2 photosynthesis is characterized by recapturing photorespiratory CO2 by RuBisCO in Kranz-like cells and is therefore physiologically intermediate between C3 and C4 photosynthesis. C2 can be interpreted as an evolutionary precursor of C4 and/or as the result of hybridization between a C3 and C4 lineage.We compared the expression of photosynthetic traits among populations of the Salsola divaricata agg. (C2) from humid subtropical to arid habitats on the coasts of the Canary Islands and Morocco and subjected them to salt and drought treatments. We screened for enhanced C4-like expression of traits related to habitat or treatment. We estimated species trees with a transcriptome datase…
The Lady from Basel's Barfüsserkirche - Molecular confirmation of the Mummy's identity through mitochondrial DNA of living relatives spanning 22 gene…
2021
Abstract The identity of the mummified Lady from the Barfusser Church in Basel, Switzerland has been unsolved for decades, despite the prominent location of the burial place in front of the choir screen. A recent multidisciplinary research approach came up with a possible candidate, Anna Catharina Bischoff who died in Basel in 1787 with an age of 69 years (1719–1787). To verify the identity of the mummy, genealogists of the Citizen Science Basel discovered three living individuals of the maternal lineage of two different family branches, separated from Anna Catharina Bischoff by up to 22 generations. In this study we compare the ancient mitochondrial DNA of the mummy recovered from a premol…
A novel isolation technique and extended characte-rization of mesenchymal stem cells from human umbilical cord matrix: disclosing new potentials for …
2008
proTRAC - a software for probabilistic piRNA cluster detection, visualization and analysis
2012
Abstract Background Throughout the metazoan lineage, typically gonadal expressed Piwi proteins and their guiding piRNAs (~26-32nt in length) form a protective mechanism of RNA interference directed against the propagation of transposable elements (TEs). Most piRNAs are generated from genomic piRNA clusters. Annotation of experimentally obtained piRNAs from small RNA/cDNA-libraries and detection of genomic piRNA clusters are crucial for a thorough understanding of the still enigmatic piRNA pathway, especially in an evolutionary context. Currently, detection of piRNA clusters relies on bioinformatics rather than detection and sequencing of primary piRNA cluster transcripts and the stringency …
Gisekia(Gisekiaceae): Phylogenetic relationships, biogeography, and ecophysiology of a poorly known C4lineage in the Caryophyllales
2014
• Premise of the study: Gisekiaceae are a monogeneric family of the core Caryophyllales distributed in arid regions of Africa and Asia. The only widespread species of the genus, Gisekia pharnaceoides, performs C4 photosynthesis based on CO2 compensation point measurements. This study investigates the C4 syndrome and its evolution in Gisekia. The infrageneric relationships, distribution and bioclimatic preferences of Gisekia are also investigated.• Methods: Leaf gas exchange characteristics, activity of Rubisco and major C4 cycle enzymes, and ultrastructural characteristics of mesophyll and bundle sheath cells are studied for Gisekia pharnaceoides. δ13C values and leaf anatomy are analyzed f…
The age and evolution of sociality in Stegodyphus spiders: a molecular phylogenetic perspective
2006
Social, cooperative breeding behaviour is rare in spiders and generally characterized by inbreeding, skewed sex ratios and high rates of colony turnover, processes that when combined may reduce genetic variation and lower individual fitness quickly. On these grounds, social spider species have been suggested to be unstable in evolutionary time, and hence sociality a rare phenomenon in spiders. Based on a partial molecular phylogeny of the genus Stegodyphus , we address the hypothesis that social spiders in this genus are evolutionary transient. We estimate the age of the three social species, test whether they represent an ancestral or derived state and assess diversification relative to s…
GFP immunogold staining, from light to electron microscopy, in mammalian cells.
2012
GFP has emerged as an important reporter for monitoring gene expression, protein localization, cell transformation and cell lineage. The development of GFP as a marker in many different biological systems has emphasized the need to image GFP at high resolution. GFP immunogold labeling with colloidal gold particles becomes essential for electron microscopy (EM) ultrastructural detection. Because of the small size, colloidal gold particles require silver enhancement, a procedure to increase the size of the particle as well as gold toning to stabilize the silver layer. GFP preembedding immunogold staining enables high quality cellular-ultrastructural EM analysis mainly for two reasons, on one …