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Molecular aspects of genotypic variation in nitrogen (N) utilization efficiency (NUtE) of wheat are largely unknown. A greenhouse experiment was designed to study the expression patterns of five genes ( TaGS1c ; TaGS2a ; TaAlaAT ; TaASN1 and TaPPDK ) involved in N metabolism in two wheat genotypes with high and low NUtEs. N-efficient (YM18) and N-inefficient (XY6) wheat genotypes were planted at low N (no N application) and high N (0.3 g N kg −1 soil) treatments. Shoots were sampled at the F3 (tillering), F7 (jointing), F10 (heading) and F11 (grain filling) stages, and expression of the five genes was quantified using real-time, reverse transcription PCR (polymerase chain reaction). The higher grain NUtE of YM18 compared to XY6 was attributed to its higher N remobilization efficiency. The expression of the five genes showed significant seasonal dynamics, and expression of genes TaGS1c , TaAlaAT and TaPPDK in YM18 increased significantly and were higher than that in XY6 at reproductive growth under either low or high N treatments. These genes may contribute to the high N remobilization efficiency of YM18 and serve as potential targets to enhance NUtE of wheat. [ABSTRACT FROM AUTHOR]

Recent evidence suggested that nonirradiated cancer-associated fibroblasts (CAFs) promoted aggressive phenotypes of cancer cells through epithelial–mesenchymal transition (EMT). Hepatoma-derived growth factor (HDGF) is a radiosensitive gene of esophageal squamous cell carcinoma (ESCC). This study aimed to investigate the effect of irradiated fibroblasts on EMT and HDGF expression of ESCC. Our study demonstrated that coculture with nonirradiated fibroblasts significantly increased the invasive ability of ESCC cells and the increased invasiveness was further accelerated when they were cocultured with irradiated fibroblasts. Scattering of ESCC cells was also accelerated by the supernatant from irradiated fibroblasts. Exposure of ESCC cells to supernatant from irradiated fibroblasts resulted in decreased E-cadherin, increased vimentin in vitro and β-catenin was demonstrated to localize to the nucleus in tumor cells with irradiated fibroblasts in vivo models. The expression of HDGF and β-catenin were increased in both fibroblasts and ESCC cells of irradiated group in vitro and in vivo models. Interestingly, the tumor cells adjoining the stromal fibroblasts displayed strong nuclear HDGF immunoreactivity, which suggested the occurrence of a paracrine effect of fibroblasts on HDGF expression. These data suggested that irradiated fibroblasts promoted invasion, growth, EMT and HDGF expression of ESCC. [ABSTRACT FROM AUTHOR]