Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relations hips. We dated the origin of insects to the Early Ordovician [~479 million years ago (Ma)], of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.
The TOR (target of rapamycin) kinase limits longevity by poorly understood mechanisms. Rapamycin suppresses the mammalian TORC1 complex, which regulates translation, and extends lifespan in diverse species, including mice. We show that rapamycin selectively blunts the pro-inflammatory phenotype of senescent cells. Cellular senescence suppresses cancer by preventing cell proliferation. However, as senescent cells accumulate with age, the senescence-associated secretory phenotype (SASP) can disrupt tissues and contribute to age-related pathologies, including cancer. MTOR inhibition suppressed the secretion of inflammatory cytokines by senescent cells. Rapamycin reduced IL6 and other cytokine mRNA levels, but selectively suppressed translation of the membrane-bound cytokine IL1A. Reduced IL1A diminished NF-κB transcriptional activity, which controls much of the SASP; exogenous IL1A restored IL6 secretion to rapamycin-treated cells. Importantly, rapamycin suppressed the ability of senescent fibroblasts to stimulate prostate tumour growth in mice. Thus, rapamycin might ameliorate age-related pathologies, including late-life cancer, by suppressing senescence-associated inflammation.
Background & Aims Aberrant activation of βcatenin and Yes-associated protein 1 (Yap1) signaling pathways have been associated with development of multiple tumor types. Yap functions as a transcriptional co-activator by interacting with TEAD DNA binding proteins. We investigated the interactions among these pathways during hepatic tumorigenesis. Methods We used immunohistochemical analysis to determine expression of β-catenin and Yap1 in liver cancer specimens collected from patients in Europe and the US, consisting of 104 hepatocellular carcinoma (HCC), 62 intrahepatic cholangiocarcinoma (ICC), and 94 hepatoblastoma samples. We assessed βcatenin and Yap1 signaling and interactions in hepatoblastoma cell lines ((HuH6, HepG2, HepT1, HC-AFW1, HepG2, and HC-AFW1); proteins were knocked down with small interfering (si)RNAs and effects on proliferation and cell death were measured. Sleeping beauty-mediated hydrodynamic transfection was used to overexpress constitutively active forms of β catenin ( N90-βcatenin) and Yap1 (YapS127A) in livers of mice; tissues were collected and histologic and immunohistochemical analyses were performed. Results We observed nuclear localization of βcatenin and Yap1 in 79% of hepatoblastoma samples, but not in most HCC or ICC tissues. Yap1 and β catenin co-precipitated in hepatoblastoma but not HCC cells. siRNA-mediated knockdown of Yap1 or β catenin in hepatoblastoma cells reduced proliferation in an additive manner. Knockdown of Yap1 reduced its ability to co-activate transcription with βcatenin; βcatenin inhibitors inactivated Yap1. Overexpression of constitutively active forms of Yap1 and βcatenin in mouse liver led to rapid tumorigenesis, with 100% mortality by 11 weeks. Tumors cells expressed both proteins, and human hepatoblastoma cells expressed common targets of their 2 signaling pathways. Yap1 binding of TEAD factors was required for tumorigenesis in mice. Conclusions β catenin and the transcriptional regulator Yap1 interact physically and are activated in most human hepatoblastoma tissues; overexpression of activated forms of these proteins in livers of mice leads to rapid tumor development. Further analysis of these mice will allow further studies of these pathways in hepatoblastoma pathogenesis and could lead to the identification of new therapeutic targets.
Aging is an independent risk factor for CKD, but the molecular mechanisms that link aging and CKD are not well understood. The antiaging protein Klotho may be an endogenous antagonist of Wnt/b-catenin signaling, which promotes fibrogenesis, suggesting that loss of Klotho may contribute to CKD through increased Wnt/b-catenin activity. Here, normal adult kidneys highly expressed Klotho in the tubular epithelium, but various models of nephropathy exhibited markedly less expression of Klotho. Loss of Klotho was closely associated with increased b-catenin in the diseased kidneys, suggesting an inverse correlation between Klotho and canonical Wnt signaling. In vitro, both full-length and secreted Klotho bound to multiple Wnts, including Wnt1, Wnt4, and Wnt7a. Klotho repressed gene transcription induced by Wnt but not by active b-catenin. Furthermore, Klotho blocked Wnt-triggered activation and nuclear translocation of b-catenin, as well as the expression of its target genes in tubular epithelial cells. Investigating potential mediators of Klotho loss in CKD, we found that TGF-b1 suppressed Klotho expression and concomitantly activated b-catenin; conversely, overexpression of Klotho abolished fibrogenic effects of TGF-b1. In two mouse models of CKD induced by unilateral ureteral obstruction or adriamycin, in vivo expression of secreted Klotho inhibited the activation of renal b-catenin and expression of its target genes. Secreted Klotho also suppressed myofibroblast activation, reduced matrix expression, and ameliorated renal fibrosis. Taken together, these results suggest that Klotho is an antagonist of endogenous Wnt/ b-catenin activity; therefore, loss of Klotho may contribute to kidney injury by releasing the repression of pathogenic Wnt/b-catenin signaling.
BackgroundNext-generation-sequencing (NGS) technologies combined with a classic DNA barcoding approach have enabled fast and credible measurement for biodiversity of mixed environmental samples. However, the PCR amplification involved in nearly all existing NGS protocols inevitably introduces taxonomic biases. In the present study, we developed new Illumina pipelines without PCR amplifications to analyze terrestrial arthropod communities.ResultsMitochondrial enrichment directly followed by Illumina shotgun sequencing, at an ultra-high sequence volume, enabled the recovery of Cytochrome c Oxidase subunit 1 (COI) barcode sequences, which allowed for the estimation of species composition at high fidelity for a terrestrial insect community. With 15.5 Gbp Illumina data, approximately 97% and 92% were detected out of the 37 input Operational Taxonomic Units (OTUs), whether the reference barcode library was used or not, respectively, while only 1 novel OTU was found for the latter. Additionally, relatively strong correlation between the sequencing volume and the total biomass was observed for species from the bulk sample, suggesting a potential solution to reveal relative abundance.ConclusionsThe ability of the new Illumina PCR-free pipeline for DNA metabarcoding to detect small arthropod specimens and its tendency to avoid most, if not all, false positives suggests its great potential in biodiversity-related surveillance, such as in biomonitoring programs. However, further improvement for mitochondrial enrichment is likely needed for the application of the new pipeline in analyzing arthropod communities at higher diversity.
Activation of the renin-angiotensin system (RAS) plays an essential role in the pathogenesis of CKD and cardiovascular disease. However, current anti-RAS therapy only has limited efficacy, partly because of compensatory upregulation of renin expression. Therefore, a treatment strategy to simultaneously target multiple RAS genes is necessary to achieve greater efficacy. By bioinformatics analyses, we discovered that the promoter regions of all RAS genes contained putative T-cell factor (TCF)/lymphoid enhancer factor ( Extensive studies over the last several decades have established that activation of the renin-angiotensin system (RAS) plays an essential role in the pathogenesis of CKD and cardiovascular disease. 1-3 RAS consists of several key components, including angiotensinogen (AGT), renin, angiotensin-converting enzyme (ACE), angiotensin II type 1 receptor (AT1), and angiotensin II type 2 receptor (AT2). Many studies indicate that, after kidney injury, intrarenal RAS is markedly activated because of concurrent upregulation of multiple RAS genes. 4,5 RAS activation contributes to kidney and cardiovascular injury through a range of mechanisms. In addition to regulating BP and hemodynamics, 6,7 angiotensin II, the principal and active mediator of RAS, activates TGF-b1 and NF-kB signaling and directly promotes renal inflammation and fibrosis. 8-10 Studies using both genetic and pharmacologic approaches have confirmed the relevance and importance of RAS activation in the development and progression of CKD and cardiovascular disease. However, current anti-RAS therapy using ACE inhibitors (ACEIs) or angiotensin II receptor
AKI is increasingly recognized as a major risk factor for progression to CKD. However, the factors governing AKI to CKD progression are poorly understood. In this study, we investigated this issue using moderate (20 minutes) and severe (30 minutes) ischemia/reperfusion injury (IRI) in mice. Moderate IRI led to acute kidney failure and transient Wnt/b-catenin activation, which was followed by the restoration of kidney morphology and function. However, severe IRI resulted in sustained and exaggerated Wnt/ b-catenin activation, which was accompanied by development of renal fibrotic lesions characterized by interstitial myofibroblast activation and excessive extracellular matrix deposition. To assess the role of sustained Wnt/b-catenin signaling in mediating AKI to CKD progression, we manipulated this signaling by overexpression of Wnt ligand or pharmacologic inhibition of b-catenin. In vivo, overexpression of Wnt1 at 5 days after IRI induced b-catenin activation and accelerated AKI to CKD progression. Conversely, blockade of Wnt/b-catenin by small molecule inhibitor ICG-001 at this point hindered AKI to CKD progression. In vitro, Wnt ligands induced renal interstitial fibroblast activation and promoted fibronectin expression. However, activated fibroblasts readily reverted to a quiescent phenotype after Wnt ligands were removed, suggesting that fibroblast activation requires persistent Wnt signaling. These results indicate that sustained, but not transient, activation of Wnt/b-catenin signaling has a decisive role in driving AKI to CKD progression. 27: 172727: -174027: , 201627: . doi: 10.1681 AKI is responsible for about 2 million deaths each year worldwide, and its incidence is rising. 1-3 AKI is increasingly common in critically ill patients, and those patients with severe AKI requiring dialysis have a mortality rate of .50%. In contrast to the traditional belief that survivors of AKI tend to fully recover renal function, there is growing evidence that patients who survive an episode of AKI will have a significant risk of developing progressive CKD and even ESRD. 1,2,4 Evidence is also mounting that the severity and frequency of AKI seem to be closely correlated with poor patient long-term outcome, 5,6 suggesting that AKI may be a predictive and causative factor for subsequent development of CKD. In this context, delineation of the underlying mechanisms governing the different courses of long-term outcome after AKI will not only shed new light on understanding the pathophysiology of AKI-CKD progression but also is instrumental in designing rational strategies for therapeutic intervention. J Am Soc NephrolWnt/b-catenin is a developmental signaling pathway that plays an essential role in regulating
Sonic hedgehog (Shh) signaling is a developmental signal cascade that plays an essential role in regulating embryogenesis and tissue homeostasis. Here, we investigated the potential role of Shh signaling in renal interstitial fibrogenesis. Ureteral obstruction induced Shh, predominantly in the renal tubular epithelium of the fibrotic kidneys. Using Gli1 lacZ knock-in mice, we identified renal interstitial fibroblasts as Shhresponding cells. In cultured renal fibroblasts, recombinant Shh protein activated Gli1 and induced a-smooth muscle actin (a-SMA), desmin, fibronectin, and collagen I expression, suggesting that Shh signaling promotes myofibroblast activation and matrix production. Blockade of Shh signaling with cyclopamine abolished the Shh-mediated induction of Gli1, Snail1, a-SMA, fibronectin, and collagen I. In vivo, the kidneys of Gli1-deficient mice were protected against the development of interstitial fibrosis after obstructive injury. In wild-type mice, cyclopamine did not affect renal Shh expression but did inhibit induction of Gli1, Snail1, and a-SMA. In addition, cyclopamine reduced matrix expression and mitigated fibrotic lesions. These results suggest that tubule-derived Shh mediates epithelial-mesenchymal communication by targeting interstitial fibroblasts after kidney injury. We conclude that Shh/Gli1 signaling plays a critical role in promoting fibroblast activation, production of extracellular matrix, and development of renal interstitial fibrosis.
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