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McGrath Dall posted an update 4 hours, 11 minutes ago
The assembly of centromeric regions has become one of the most intractable tasks in whole-genome sequencing due to the enrichment of highly repetitive DNA sequences in most eukaryotic centromeres. Here, we describe a method used to identify centromeric DNAs through chromatin immunoprecipitation and sequencing (ChIP-seq). By mapping ChIP-seq reads, centromeric regions can be indicated in genome assemblies. We demonstrated that the assembly quality of centromeres obtained using ChIP-seq mapping can reflect and indicate the quality of a whole-genome assembly. We discuss an expected ‘high-quality’ centromere assembly obtained via centromere ChIP-seq mapping.The genus Schizodon is part of a group of headstanders and relatives (Family Anostomidae) that are widespread and ecologically important fishes in South American rivers. Schizodon includes 15 nominal species but their taxonomy has been challenging due to paucity of decisive characters to diagnose species. We present new molecular data to assess species boundaries or molecular operational taxonomic units (MOTUs), and to infer phylogenetic relationships among species. Evidence from two mitochondrial and three nuclear genes was used in these analyses. Mitochondrial DNA data for 112 specimens (from 11 nominal species) supported 13 consensus MOTUs, six of which matched valid nominal species (Schizodon borellii, S. fasciatus, S. intermedius, S. isognathus, S. knerii and S. scotorhabdotus). The nominal species Schizodon vittatus, S. nasutus, and S. dissimilis were subdivided into two MOTUs each, revealing either cryptic species or strong population structuring. In contrast, S. platae and S. jacuiensis constituted a sity.Ghrelin is a 28-amino acid peptide hormone that regulates ovarian steroid hormone synthesis; however, there is limited evidence regarding the regulation of this pathway by ghrelin in mice ovary. Thus, we aimed to investigate whether central ghrelin action plays a role in murine reproductive health by inhibiting steroid synthesis. Further, we sought to examine the mechanism of central ghrelin action in ovarian steroid hormone synthesis. After the administration of intracerebroventricular ghrelin (1 nmol), we found reduced serum concentrations of oestradiol and progesterone and reduced secretion of follicle-stimulating hormone and luteinising hormone. Although ghrelin reduced 3β-hydroxysteroid dehydrogenase mRNA and protein levels in the hypothalamus, it did not affect the expression of steroidogenic acute regulatory protein and cytochrome P450 17A1. In the ovary, central ghrelin regulation indirectly inhibited the mRNA and protein levels of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase. Moreover, no changes were observed in the expression of proliferating cell nuclear antigen and phosphorylation of extracellular signal-regulated kinase. We hypothesised that central ghrelin regulation suppressed serum oestradiol and progesterone levels by indirectly inhibiting the expression of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase in the ovary. In this regulation, the suppressed secretion of the follicle-stimulating hormone and luteinising hormone in the pituitary by ghrelin could be involved. Furthermore, hypothalamic 3β-hydroxysteroid dehydrogenase expression is reduced by ghrelin injection.Vessel co-option is an alternative strategy by which tumour cells vascularize and gain access to nutrients to support tumour growth, survival and metastasis. In vessel co-option, the cancer cells move towards the pre-existing vasculature and hijack them. Vessel co-option is adopted by a wide range of human tumours including colorectal cancer liver metastases (CRCLM) and is responsible for the effectiveness of treatment in CRCLM. Furthermore, vessel co-option is an intrinsic feature and an acquired mechanism of resistance to anti-angiogenic treatment. In this review, we describe the microenvironment, the molecular players, discovered thus far of co-opting CRCLM lesions and propose a theoretical model. We also highlight key unanswered questions that are critical to improving our understanding of CRCLM vessel co-option and for the development of effective approaches for the treatment of co-opting tumours.Several studies have shown that cancer cells can be “phenotypically reversed”, thus achieving a “tumor reversion”, by losing malignant hallmarks as migrating and invasive capabilities. These findings suggest that genome activity can switch to assume a different functional configuration, i.e. a different Gene Regulatory Network pattern. Indeed, once “destabilized”, cancer cells enter into a critical transition phase that can be adequately “oriented” by yet unidentified morphogenetic factors – acting on both cells and their microenvironment – that trigger an orchestrated array of structural and epigenetic changes. Such process can bypass genetic abnormalities, through rerouting cells toward a benign phenotype. Oocytes and embryonic tissues, obtained by animals and humans, display such “reprogramming” capability, as a number of yet scarcely identified embryo-derived factors can revert the malignant phenotype of several types of tumors. Mechanisms involved in the reversion process include the modification of cell-microenvironment cross talk (mostly through cytoskeleton reshaping), chromatin opening, demethylation, and epigenetic changes, modulation of biochemical pathways, comprising TCTP-p53, PI3K-AKT, FGF, Wnt, and TGF-β-dependent cascades. Results herein discussed promise to open new perspectives not only in the comprehension of cancer biology but also toward different therapeutic options, as suggested by a few preliminary clinical studies.Gliomas are aggressive brain tumors with high mortality rate. Over the past several years, non-coding RNAs, specifically the long non-coding RNAs (lncRNAs), have emerged as biomarkers of considerable interest. Emerging data reveals distinct patterns of expressions of several lncRNAs in the glioma tissues, relative to their expression in normal brains. Apitolisib datasheet This has led to the speculation for putative exploitation of lncRNAs as diagnostic biomarkers as well as biomarkers for targeted therapy. With a focus on lncRNAs that have shown promise as epigenetic biomarkers in the proliferation, migration, invasion, angiogenesis and metastasis in various glioma models, we discuss several such lncRNAs. The data from cell line / animal model-based studies as well as analysis from human patient samples is presented for the most up-to-date information on the topic. Overall, the information provided herein makes a compelling case for further evaluation of lncRNAs in clinical settings.