Project description:Conflicting relationships have been found between diversification rate and temperature across disparate clades of life. Here, we use a supermatrix comprising nearly 20,000 species of rosids-a clade of ~25% of all angiosperm species-to understand global patterns of diversification and its climatic association. Our approach incorporates historical global temperature, assessment of species' temperature niche, and two broad-scale characterizations of tropical versus non-tropical niche occupancy. We find the diversification rates of most subclades dramatically increased over the last 15 million years (Myr) during cooling associated with global expansion of temperate habitats. Climatic niche is negatively associated with diversification rates, with tropical rosids forming older communities and experiencing speciation rates ~2-fold below rosids in cooler climates. Our results suggest long-term cooling had a disproportionate effect on non-tropical diversification rates, leading to dynamic young communities outside of the tropics, while relative stability in tropical climes led to older, slower-evolving but still species-rich communities.
Project description:Recent studies demonstrate both basal and luminal cells of the prostate gland can initiate tumorigenesis upon oncogenic transformation. However, it remains unclear how molecular mechanisms operating within each cell lineage contribute to the initiation and progression of the prostate cancer. Here we investigate functions of individual miRNAs using genetically engineered mouse models. By both quantitative miR-Seq and in situ hybridization, we identify microRNA-205 (miR-205) as the most highly expressed miRNA and specific to the basal cells in the prostate. MicroRNA-205 expression is further elevated in the basal cells in the well-established Pten null tumorigenic mouse model. To investigate the role of miR-205 in Pten-deletion mediated tumorigenesis, we generated a Pten/miR-205 double knockout mouse model. Concurrent deletion of both miR-205 and Pten significantly compromised tumor progression in both basal and luminal compartments. We observed significantly reduced tumor size and compromised proliferation in both basal and luminal cells. We have previously demonstrated a critical requirement of miR-205 for maintaining the PI(3)K signaling and pAkt levels in skin stem cells. Consistent with this role, we observed strong reduction of pAkt and significantly increased cellular senescence in the basal cells of the dKO, compared to the Pten KO alone. These results suggest that miR-205 is cell-autonomously required for the tumorigenesis of the basal cells. Taken together, we have identified miR-205 as an important regulator in prostate cancer. Our study also reveals an essential and unexpected role of the basal cells for promoting prostate tumorigenesis.
Project description:RNA-Seq data for 205 mature neutrophil sample(s). 205 run(s), 205 experiment(s), 205 analysis(s) on human genome GRCh37. Analysis documentation available at http://ftp.ebi.ac.uk/pub/databases/blueprint/blueprint_Epivar/protocols/README_rnaseq_analysis_sanger_20160816
Project description:Rosids are a monophyletic group that includes approximately 70,000 species in 140 families, and they are found in a variety of habitats and life forms. Many important crops such as fruit trees and legumes are rosids. The evolutionary success of this group may have been influenced by their ability to produce flavonoids, secondary metabolites that are synthetized through a branch of the phenylpropanoid pathway where chalcone synthase is a key enzyme. In this work, we studied the evolution of the chalcone synthase gene family in 12 species belonging to the rosid clade. Our results show that the last common ancestor of the rosid clade possessed six chalcone synthase gene lineages that were differentially retained during the evolutionary history of the group. In fact, of the six gene lineages that were present in the last common ancestor, 7 species retained 2 of them, whereas the other 5 only retained one gene lineage. We also show that one of the gene lineages was disproportionately expanded in species that belonged to the order Fabales (soybean, barrel medic and Lotus japonicas). Based on the available literature, we suggest that this gene lineage possesses stress-related biological functions (e.g., response to UV light, pathogen defense). We propose that the observed expansion of this clade was a result of a selective pressure to increase the amount of enzymes involved in the production of phenylpropanoid pathway-derived secondary metabolites, which is consistent with the hypothesis that suggested that lineage-specific expansions fuel plant adaptation.
Project description:BackgroundRosids are a major clade in the angiosperms containing 13 orders and about one-third of angiosperm species. Recent molecular analyses recognized two major groups (i.e., fabids with seven orders and malvids with three orders). However, phylogenetic relationships within the two groups and among fabids, malvids, and potentially basal rosids including Geraniales, Myrtales, and Crossosomatales remain to be resolved with more data and a broader taxon sampling. In this study, we obtained DNA sequences of the mitochondrial matR gene from 174 species representing 72 families of putative rosids and examined phylogenetic relationships and phylogenetic utility of matR in rosids. We also inferred phylogenetic relationships within the "rosid clade" based on a combined data set of 91 taxa and four genes including matR, two plastid genes (rbcL, atpB), and one nuclear gene (18S rDNA).ResultsComparison of mitochondrial matR and two plastid genes (rbcL and atpB) showed that the synonymous substitution rate in matR was approximately four times slower than those of rbcL and atpB; however, the nonsynonymous substitution rate in matR was relatively high, close to its synonymous substitution rate, indicating that the matR has experienced a relaxed evolutionary history. Analyses of our matR sequences supported the monophyly of malvids and most orders of the rosids. However, fabids did not form a clade; instead, the COM clade of fabids (Celastrales, Oxalidales, Malpighiales, and Huaceae) was sister to malvids. Analyses of the four-gene data set suggested that Geraniales and Myrtales were successively sister to other rosids, and that Crossosomatales were sister to malvids.ConclusionCompared to plastid genes such as rbcL and atpB, slowly evolving matR produced less homoplasious but not less informative substitutions. Thus, matR appears useful in higher-level angiosperm phylogenetics. Analysis of matR alone identified a novel deep relationship within rosids, the grouping of the COM clade of fabids and malvids, which was not resolved by any previous molecular analyses but recently suggested by floral structural features. Our four-gene analysis supported the placements of Geraniales, Myrtales at basal nodes of the rosid clade and placed Crossosomatales as sister to malvids. We also suggest that the core part of rosids should include fabids, malvids and Crossosomatales.
Project description:Through phenotypical study, we found that miR-205 can promote hair growth. The goal of this study is to determine how miR-205 effects epithelial cellular states and how miR-205 promotes hair growth at single cell level.
Project description:Through phenotypical study, we found that miR-205 can promote hair growth. The goals of this study is to identify direct targets of miR-205 in hair follicle stem cells and determine whether and how miR-205 promotes hair growth by activating hair follicle stem cell.