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Zebrafish regenerate heart muscle through division of pre-existing cardiomyocytes. To discover underlying regulation, we assess transcriptome datasets for dynamic gene networks during heart regeneration and identify suppression of genes associated with the transcription factor Tp53. Cardiac damage leads to fluctuation of Tp53 protein levels, concomitant with induced expression of its central negative regulator, mdm2, in regenerating cardiomyocytes. Zebrafish lacking functional Tp53 display increased indicators of cardiomyocyte proliferation during regeneration, whereas transgenic Mdm2 blockade inhibits injury-induced cardiomyocyte proliferation. Induced myocardial overexpression of the mitogenic factors Nrg1 or Vegfaa in the absence of injury also upregulates mdm2 and suppresses Tp53 levels, and tp53 mutations augment the mitogenic effects of Nrg1. mdm2 induction is spatiotemporally associated with markers of de-differentiation in injury and growth contexts, suggesting a broad role in cardiogenesis. Our findings reveal myocardial Tp53 suppression by mitogen-induced Mdm2 as a regulatory component of innate cardiac regeneration.Multidonor antibodies are of interest for vaccine design because they can in principle be elicited in the general population by a common set of immunogens. For influenza, multidonor antibodies have been observed against the hemagglutinin (HA) stem, but not the immunodominant HA head. Here, we identify and characterize a multidonor antibody class (LPAF-a class) targeting the HA head. This class exhibits potent viral entry inhibition against H1N1 A/California/04/2009 (CA09) virus. LPAF-a class antibodies derive from the HV2-70 gene and contain a "Tyr-Gly-Asp"-motif, which occludes the HA-sialic acid binding site as revealed by a co-crystal structure with HA. Both germline-reverted and mature LPAF antibodies potently neutralize CA09 virus and have nanomolar affinities for CA09 HA. Moreover, increased frequencies for LPFA-a class antibodies are observed in humans after a single vaccination. Overall, this work highlights the identification of a multidonor class of head-directed influenza-neutralizing antibodies and delineates the mechanism of their recurrent elicitation in humans.The heart manifests hypertrophic growth in response to high blood pressure, which may decompensate and progress to heart failure under persistent stress. Metabolic remodeling is an early event in this process. However, its role remains to be fully characterized. Here, we show that lactate dehydrogenase A (LDHA), a critical glycolytic enzyme, is elevated in the heart in response to hemodynamic stress. Cardiomyocyte-restricted deletion of LDHA leads to defective cardiac hypertrophic growth and heart failure by pressure overload. Silencing of LDHA in cultured cardiomyocytes suppresses cell growth from pro-hypertrophic stimulation in vitro, while overexpression of LDHA is sufficient to drive cardiomyocyte growth. Furthermore, we find that lactate is capable of rescuing the growth defect from LDHA knockdown. Mechanistically, lactate stabilizes NDRG3 (N-myc downregulated gene family 3) and stimulates ERK (extracellular signal-regulated kinase). HA130 Our results together suggest that the LDHA/NDRG3 axis may play a critical role in adaptive cardiomyocyte growth in response to hemodynamic stress.High-grade serous ovarian carcinoma (HGSOC) is the fifth leading cause of cancer-related deaths of women in the United States. Disease-associated mutations have been identified by the Cancer Genome Atlas Research Network. However, aside from mutations in TP53 or the RB1 pathway that are common in HGSOC, the contributions of mutation combinations are unclear. Here, we report CRISPR mutagenesis of 20 putative HGSOC driver genes to identify combinatorial disruptions of genes that transform either ovarian surface epithelium stem cells (OSE-SCs) or non-stem cells (OSE-NSs). Our results support the OSE-SC theory of HGSOC initiation and suggest that most commonly mutated genes in HGSOC have no effect on OSE-SC transformation initiation. Our results indicate that disruption of TP53 and PTEN, combined with RB1 disruption, constitutes a core set of mutations driving efficient transformation in vitro. The combined data may contribute to more accurate modeling of HGSOC development.CD8+ tissue-resident memory T cells (TRM) persist at sites of previous infection, where they provide rapid local protection against pathogen challenge. CD8+ TRM expressing the α1 chain (CD49a) of integrin VLA-1 have been identified within sites of resolved skin infection and in vitiligo lesions. We demonstrate that CD49a is expressed early following T cell activation in vivo, and TGF-β and IL-12 induce CD49a expression by CD8+ T cells in vitro. Despite this rapid expression, CD49a is not required for the generation of a primary CD8+ T cell response to cutaneous herpes simplex virus (HSV) infection, migration of CD8+ T cells across the epidermal basement membrane, or positioning of TRM within basal epidermis. Rather, CD49a supports CD8+ TRM persistence within skin, regulates epidermal CD8+ TRM dendritic extensions, and increases the frequency of IFN-γ+ CD8+ TRM following local antigen challenge. Our results suggest that CD49a promotes optimal cutaneous CD8+ TRM-mediated immunity.Cell-to-cell variability in signal transduction in biological systems is often considered noise. However, intercellular variation (i.e., cell-to-cell variability) has the potential to enable individual cells to encode different information. Here, we show that intercellular variation increases information transmission of skeletal muscle. We analyze the responses of multiple cultured myotubes or isolated skeletal muscle fibers as a multiple-cell channel composed of single-cell channels. We find that the multiple-cell channel, which incorporates intercellular variation as information, not noise, transmitted more information in the presence of intercellular variation than in the absence according to the "response diversity effect," increasing in the gradualness of dose response by summing the cell-to-cell variable dose responses. We quantify the information transmission of human facial muscle contraction during intraoperative neurophysiological monitoring and find that information transmission of muscle contraction is comparable to that of a multiple-cell channel. Thus, our data indicate that intercellular variation can increase the information capacity of tissues.We report the free-energy landscape and thermodynamics of the protein-protein association responsible for the drug-induced multimerization of HIV-1 integrase (IN). Allosteric HIV-1 integrase inhibitors promote aberrant IN multimerization by bridging IN-IN intermolecular interactions. However, the thermodynamic driving forces and kinetics of the multimerization remain largely unknown. Here, we explore the early steps in the IN multimerization by using umbrella sampling and unbiased molecular dynamics simulations in explicit solvent. In direct simulations, the two initially separated dimers spontaneously associate to form near-native complexes that resemble the crystal structure of the aberrant tetramer. Most strikingly, the effective interaction of the protein-protein association is very short-ranged the two dimers associate rapidly within tens of nanoseconds when their binding surfaces are separated by d ≤ 4.3 Å (less than two water diameters). Beyond this distance, the oligomerization kinetics appears to be posed by entropy.We consider the stationary solution for the Ca2+ concentration near a point Ca2+ source describing a single-channel Ca2+ nanodomain in the presence of a single mobile Ca2+ buffer with 11 Ca2+ binding. We present computationally efficient approximants that estimate stationary single-channel Ca2+ nanodomains with great accuracy in broad regions of parameter space. The presented approximants have a functional form that combines rational and exponential functions, which is similar to that of the well-known excess buffer approximation and the linear approximation but with parameters estimated using two novel, to our knowledge, methods. One of the methods involves interpolation between the short-range Taylor series of the free buffer concentration and its long-range asymptotic series in inverse powers of distance from the channel. Although this method has already been used to find Padé (rational-function) approximants to single-channel Ca2+ and buffer concentrations, extending this method to interpolants combining exponential and rational functions improves accuracy in a significant fraction of the relevant parameter space. A second method is based on the variational approach and involves a global minimization of an appropriate functional with respect to parameters of the chosen approximations. An extensive parameter-sensitivity analysis is presented, comparing these two methods with previously developed approximants. Apart from increased accuracy, the strength of these approximants is that they can be extended to more realistic buffers with multiple binding sites characterized by cooperative Ca2+ binding, such as calmodulin and calretinin.We previously found that ginsenoside 20(S)-Rg3 diminishes the proliferative and invasive capacities of ovarian cancer cells by decreasing miR-4425 level. Yet the mechanism of action of miR-4425 in ovarian cancer remains unclear. Here we report that miR-4425 is upregulated in ovarian cancer tissues relative to normal ovarian tissues, and transfection of miR-4425 inhibitor impairs the proliferation, migration and invasion of SKOV3 and 3AO ovarian cancer cells. Further, miR-4425 antagomiR reduces cell proliferation in a subcutaneous SKOV3 xenograft model using BALB/c nude mice. We identifies farnesyl-diphosphate farnesyltransferase 1 (FDFT1) as a direct target of miR-4425 by Western blotting and a luciferase reporter assay. Forced expression of FDFT1 via transfection of an FDFT1-expressing plasmid into ovarian cancer cells not only retards cell proliferation, motility and invasiveness, but also negates the tumorigenic properties of a miR-4425 mimic. By contrast, silencing of FDFT1 by siRNAs abrogates suppression of the proliferation, migration and invasion of ovarian cancer cells treated with a miR-4425 inhibitor. Finally, transfection of either a miR-4425 mimic or FDFT1 siRNAs into 20(S)-Rg3-treated ovarian cancer cells counteracts the tumor-inhibitory activity of the ginsenoside. In conclusion, 20(S)-Rg3 exerts anti-ovarian cancer activity by downregulating oncogenic miR-4425 that inhibits the expression of the tumor suppressor gene FDFT1. These results expand our current understanding of the molecular pathways leading to ovarian cancer progression, and unveil the mechanism of action of 20(S)-Rg3 in ovarian cancer inhibition.High-risk hospital-associated multidrug-resistant (MDR) Enterococcus faecalis clonal complexes (CCs) such as CC2 and CC87 are enriched with virulence determinants that help to accumulate, colonize, and cause serious nosocomial infections. The aim of this study was to establish the epidemiology and clonal composition of 134 clinical E. faecalis isolates and to link molecular typing data with antimicrobial resistance and virulence determinants. All isolates were identified by conventional methods and confirmed by polymerase chain reaction (PCR) (16srRNA gene and ddl genes of E. faecalis/ E. faecium) in 5-years. Disc diffusion test was performed on all strains. We screened all E. faecalis for aac(6')-aph(2″), vanA, and vanB resistance genes, and aggregation substance-asa1, cytolysin-cylA, collagen-binding protein-ace, enterococcal surface protein-esp, gelatinase-gelE, and hyaluronidase-hyl virulence genes by PCR. Representative isolates of E. faecalis were characterized by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST).

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