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Lymphoid Enhancer Factor-1 (LEF-1) is a member of a family of transcription factors that function as downstream mediators of the Wnt signal transduction pathway. In the absence of Wnt signals, specific LEF/TCF isoforms repress rather than activate gene targets through recruitment of the co-repressor CtBP. Characterization of the full-length human LEF-1 gene locus and its complete set of mRNA products shows that this family member exists as a unique set of alternatively spliced isoforms; none are homologous to TCF-1E/TCF-4E. Therefore LEF-1 is distinct from its TCF family members in that it cannot engage in activities specific to this isoform such as recruitment of the co-repressor CtBP. Expression of alternatively spliced LEF-1 isoforms are driven by a promoter that is highly active in lymphocyte cell lines. Transcription initiates within a TATA-less core promoter region that contains consensus binding sites for Sp1, an E box, an Initiator element and a LEF/TCF binding site, all juxtaposed to the start sites of transcription. The promoter is most active in a B lymphocyte cell line (Raji) in which the endogenous LEF-1 gene is silent, suggesting that the promoter region is actively repressed by a silencing mechanism.

The sediment delivery ratio (SDR) is an important index for understanding sediment erosion, transportation and deposition features in a river basin. Based on the commonly accepted definition of SDR and the characteristics of the sediment delivery process in hyper-concentrated flow areas of the Loess Plateau, China, a new model for computing the SDR is proposed. The model is a functional relation of fractional form, in which the denominator is the surface runoff of the basin, and the numerator is the water volume needed for saturated sediment discharge in the controlling hydrological station at the exit of the basin when the saturated sediment load is equal to the measured sediment load. Using the proposed SDR equation, the long-term series of SDRs in the Yanhe River basin, a typical hyperconcentrated flow basin in the Loess Plateau, were calculated from 1952 to 2010. The results show that the long-term annual average SDR in the Yanhe River basin was 0.92, which is consistent with the results of previous studies; this finding confirms the validity and effectiveness of the method. The proposed method only requires gauge data of sediment concentration, sediment delivery rate, sediment delivery volume, and runoff ratio from hydrological stations, which makes it easy to use, and it can be used to easily estimate soil erosion in the basin. [ABSTRACT FROM AUTHOR]

The study of the magnetism and optical properties of semiconductor materials by defect engineering has attracted much attention because of their potential uses in spintronic and optoelectronic devices. In this paper, first-principle calculations discloses that cationic vacancy formation energy of the doped wurtzite materials can be sharply decreased due to alkali metal dopants and shows that their magnetic properties strongly depend on defect and doping concentration. This effect can be ascribed to the volume change induced by foreign elements doped into the host system and atomic population's difference. The symmetric deformation induced by biaxial strain can further regulate this behavior. Our results suggest that the formation of cationic vacancy can be tailored by strain engineering and dopants incorporation. [ABSTRACT FROM AUTHOR]

OBJECTIVE: As a result of gene-environment interactions, the incidence of atherosclerosis (AS) is rapidly increasing worldwide. Autophagy in endothelial cells is a key process of AS and is difficult to control when it becomes excessive in the end stage of AS. MATERIALS AND METHODS: In this study, we found increased expression levels of ZNF295- AS1 in the serum of AS patients, as well as in ox- LDL-treated HUVECs. The autophagy level was also upregulated in both samples. We demonstrated that ZNF295-AS1 may interact directly with miR-508-5p to act as a miR-508-5p sponge. The negative relationship between ZNF295-AS1 and miR-508-5p indicated that ZNF295-AS1 may be an upstream suppressor of miR-508-5p. RESULTS: ATG7 plays a critical role in autophagy and was predicted to be a target of miR-508- 5p. Therefore, we overexpressed miR-508-5p, which reduced the expression level of ATG7, enhanced cell proliferation and prevented autophagy. These data indicated that the ZNF295-AS1/miR-508-5p/ATG7 axis may participate in autophagy regulation in ox-LDL-treated HUVECs. The subsequent rescue experiments revealed the specificity of the ZNF295-AS1/miR-508-5p/ATG7 axis in the contribution of ZNF295-AS1 to autophagy. CONCLUSIONS: Overall, our findings demonstrate a novel mechanism by which ZNF295-AS1 silencing regulates ATG7 reduction and inhibits autophagy, which may delay the progression of AS. The ZNF295-AS1/miR-508-5p/ATG7 axis may be of therapeutic significance in AS. [ABSTRACT FROM AUTHOR]