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Current staging is inadequate for predicting clinical outcome of esophageal squamous cell carcinoma ( ESCC). Aberrant expression of LOXL2 and actin-related proteins plays important roles in ESCC. Here, we aimed to develop a novel molecular signature that exceeds the power of the current staging system in predicting ESCC prognosis. We found that LOXL2 colocalized with filamentous actin in ESCC cells, and gene set enrichment analysis ( GSEA) showed that LOXL2 is related to the actin cytoskeleton. An ESCC-specific protein-protein interaction ( PPI) network involving LOXL2 and actin-related proteins was generated based on genome-wide RNA-seq in 15 paired ESCC samples, and the prognostic significance of 14 core genes was analyzed. Using risk score calculation, a three-gene signature comprising LOXL2, CDH1, and FN1 was derived from transcriptome data of patients with ESCC. The high-risk three-gene signature strongly correlated with poor prognosis in a training cohort of 60 patients ( P = 0.003). In mRNA and protein levels, the prognostic values of this signature were further validated in 243 patients from a testing cohort ( P = 0.001) and two validation cohorts ( P = 0.021, P = 0.007). Furthermore, Cox regression analysis revealed that the signature was an independent prognostic factor. Compared with using the signature or TNM stage alone, the combined model significantly enhanced the accuracy in evaluating ESCC prognosis. In conclusion, our data reveal that the tumor-promoting role of LOXL2 in ESCC is mediated by perturbing the architecture of actin cytoskeleton through its PPIs. We generated a novel three-gene signature ( PPI interfaces) that robustly predicts poor clinical outcome in ESCC patients. [ABSTRACT FROM AUTHOR]

Background: Plant profilin genes encode core cell-wall structural proteins and are evidenced for their up-regulation under cotton domestication. Notwithstanding striking discoveries in the genetics of cell-wall organization in plants, little is explicit about the manner in which profilin-mediated molecular interplay and corresponding networks are altered, especially during cellular signalling of apical meristem determinacy and flower development. Results: Here we show that the ectopic expression of GhPRF1 gene in tobacco resulted in the hyperactivation of apical meristem and early flowering phenotype with increased flower number in comparison to the control plants. Spatial expression alteration in CLV1, a key meristem-determinacy gene, is induced by the GhPRF1 overexpression in a WUS-dependent manner and mediates cell signalling to promote flowering. But no such expression alterations are recorded in the GhPRF1-RNAi lines. The GhPRF1 transduces key positive flowering regulator AP1 gene via coordinated expression of FT4, SOC1, FLC1 and FT1 genes involved in the apical-to-floral meristem signalling cascade which is consistent with our in silico profilin interaction data. Remarkably, these positive and negative flowering regulators are spatially controlled by the Actin-Related Protein (ARP) genes, specifically ARP4 and ARP6 in proximate association with profilins. This study provides a novel and systematic link between GhPRF1 gene expression and the flower primordium initiation via up-regulation of the ARP genes, and an insight into the functional characterization of GhPRF1 gene acting upstream to the flowering mechanism. Also, the transgenic plants expressing GhPRF1 gene show an increase in the plant height, internode length, leaf size and plant vigor. Conclusions: Overexpression of GhPRF1 gene induced early and increased flowering in tobacco with enhanced plant vigor. During apical meristem determinacy and flower development, the GhPRF1 gene directly influences key flowering regulators through ARP-genes, indicating for its role upstream in the apical-to-floral meristem signalling cascade. [ABSTRACT FROM AUTHOR]

Aberrant expression of master phenotype regulators or alterations in their downstream pathways in lung flbroblasts may play a central role in idiopathic pulmonary flbrosis (IPF). Interrogating IPF flbroblast transcriptome datasets, we identifled Forkhead Box F1 (FOXF1), a DNA-binding protein required for lung development, as a candidate actor in IPF. Thus we determined FOXF1 expression levels in flbroblasts cultured from normal or IPF lungs in vitro, and explored FOXF1 functions in these cells using transient and stable loss-of-function and gain-of-function models. FOXF1 mRNA and protein were expressed at higher levels in IPF flbroblasts compared with normal flbroblasts (mRNA: +44%, protein: +77%). Immunohistochemistry showed FOXF1 expression in nuclei of bronchial smooth muscle cells, endothelial cells, and lung flbroblasts including flbroblastic foci of IPF lungs. In normal lung flbroblasts, FOXF1 repressed cell growth and expression of collagen-1 (COL1) and actin-related protein 2/3 complex, subunit 2 (ARPC2). ARPC2 knockdown inhibited cell growth and COL1 expression, consistent with FOXF1 acting in part through ARPC2 repression. In IPF flbroblasts, COL1 and ARPC2 repression by FOXF1 was blunted, and FOXF1 did not repress growth. FOXF1 expression was induced by the antiflbrotic mediator prostaglandin E2 and repressed by the proflbrotic cytokine transforming growth factor-β1 in both normal and IPF lung flbroblasts. Ex vivo, FOXF1 knockdown conferred CCL-210 lung flbroblasts the ability to implant in uninjured mouse lungs. In conclusion, FOXF1 functions and regulation were consistent with participation in antiflbrotic pathways. Alterations of pathways downstream of FOXF1 may participate to flbrogenesis in IPF flbroblasts. [ABSTRACT FROM AUTHOR]

Infertility is an area of increasing in life science research. Although follicular maturation disorders and anovulation are the primary causations of infertility, its molecular mechanism is not well understood. Recent research has shown that microRNAs (miRNAs) might play an important role in the regulation of ovarian follicle development and maturation. In this study, the expression of miRNAs in metaphase I (MI) oocytes treated with or without insulin-like growth factor 1 (IGF-1) was observed by microRNA microarray analysis. Results show that 145 miRNAs were up-regulated and 200 miRNAs were down-regulated in MI oocytes after IGF-1 treatment. MiR-133b, which was up-regulated more than 30-fold, was chosen for further research. As a potential target of miR133b, transgelin 2 (TAGLN2) gene was down-regulated, at both transcription and translation levels, in miR-133b- over-expressed 293T cells, but TAGLN2 was up-regulated when the expression of miR-133b was inhibited. Furthermore, the expression level of TAGLN2 in the ovaries of 8-week- old mice was higher than that observed in 4-week-old mice. Immunofluorescence experiments showed that TAGLN2 was located in the cytoplasm. In general, our results indicate that miR-133b may play important roles in the growth and maturation of oocytes by regulating its potential target, TAGLN2, at both transcription and translation levels. Therefore, our research provides a potential new target for infertility therapy. [ABSTRACT FROM AUTHOR]

Abstract: Background: Prognostication and therapeutic evaluation of urothelial carcinomas significantly depends on the depth of invasion. The assessment of invasion on routine histopathological sections may be difficult in some cases. Fascin is an actin-bundling protein involved in tumor cell migration with enhanced expression associated with invasive tumors. The data available on fascin-1 expression in urothelial carcinoma however is limited. To characterize fascin-1 expression in urothelial neoplasms and its correlation with invasiveness in urothelial carcinomas. Methods: A descriptive study design wherein fascin-1 immunoreactivity was studied in 126 urothelial neoplasms using monoclonal antibody against fascin by immunohistochemistry. 52/126 (41.26%) were low grade carcinomas (48/52 stage pTa and 4/52 stage pT1), 46/126 (36.5%) high grade carcinomas (13/46 stage pTa, 8/46 stage pT1 and 25/46 stage pT2), 02/126 carcinoma-in-situ, 03/126 papilloma, 12/126 papillary urothelial neoplasm of uncertain malignant potential and 11/126 were other variants of urothelial carcinomas. Fascin-1 cytoplasmic immunoreactivity was assessed semiquantitatively in terms of extent, intensity and a combined immunoreactivity score. Correlation between immunoreactivity scores and invasiveness was evaluated using Pearson's chi-square (χ2) and Nonparametric Spearman rho (ρ) correlation coefficient two tailed. Results: The scores for intensity, extent and combined immunoreactivity were significantly higher in invasive carcinomas. In addition, strong staining was observed exclusively in invasive carcinomas. None of the pTa tumors demonstrated intense staining, including those categorized as high grade carcinomas. Conclusion: Fascin-1 overexpression may be used as a marker in urothelial carcinomas where it is morphologically difficult to determine the status of invasion. [Copyright &y& Elsevier]

Highlights: [•] Laminar shear stress (LSS) enhances endothelial wound healing in vitro. [•] LSS increases gene expression of actin binding proteins such as synaptopodin (SYNPO). [•] siRNA-mediated suppression of SYNPO inhibits endothelial wound healing by LSS. [•] Overexpression of exogenous SYNPO enhances wound healing in the absence of LSS. [Copyright &y& Elsevier]

The packaging of DNA into nucleosomal structures limits access for templated processes such as transcription and DNA repair. The repositioning or ejection of nucleosomes is therefore critically important for regulated events, including gene expression. This activity is provided by chromatin remodeling complexes, or remodelers, which are typically large, multisubunit complexes that use an ATPase subunit to translocate the DNA. Many remodelers contain pairs or multimers of actin-related proteins (ARP5) that contact the helicase-SANT-associated (HSA) domain within the catalytic ATPase subunit and are thought to regulate ATPase activity. Here, we determined the structure of a four-protein subcomplex within the SWI/SNF remodeler that comprises the Snf2 HSA domain, Arp7, Arp9, and repressor of Tyl transposition, gene 102 (Rtt102). Surprisingly, unlike characterized actin-actin associations, the two ARPs pack like spoons and straddle the HSA domain, which forms a 92-Å-long helix. The ARP-HSA inter- actions are reminiscent of contacts between actin and many binding partners and are quite different from those in the Arp2/3 complex. Rtt102 wraps around one side of the complex in a highly extended conformation that contacts both ARP5 and therefore stabilizes the complex, yet functions to reduce by ~2.4-fold the remodeling and ATPase activity of complexes containing the Snf2 ATPase domain. Thus, our structure provides a foundation for developing models of remodeler function, including mechanisms of coupling between ARP5 and the ATPase translocation activity. [ABSTRACT FROM AUTHOR]

The spatial organization of chromatin in the nucleus contributes to genome function and is altered during the differentiation of normal and tumorigenic cells. Although nuclear actin-related proteins (Arps) have roles in the local alteration of chromatin structure, it is unclear whether they are involved in the spatial positioning of chromatin. In the interphase nucleus of vertebrate cells, gene-dense and gene-poor chromosome territories (CTs) are located in the center and periphery, respectively. We analyzed chicken DT40 cells in which Arp6 had been knocked out conditionally, and showed that the radial distribution of CTs was impaired in these knockout cells. Arp6 is an essential component of the SRCAP chromatin remodeling complex, which deposits the histone variant H2A.Z into chromatin. The redistribution of CTs was also observed in H2A.Z-deficient cells for gene-rich microchromosomes, but to lesser extent for gene-poor macrochromosomes. These results indicate that Arp6 and H2A.Z contribute to the radial distribution of CTs through different mechanisms. Microarray analysis suggested that the localization of chromatin to the nuclear periphery per se is insufficient for the repression of most genes. [ABSTRACT FROM AUTHOR]