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Sox9 is a direct transcriptional activator of cartilage-specific extracellular matrix genes and has essential roles in chondrogenesis. Mutations in or around the SOX9 gene cause campomelic dysplasia or Pierre Robin Sequence. However, Sox9-dependent transcriptional control in chondrogenesis remains largely unknown. Here we identify Wwp2 as a direct target of Sox9. Wwp2 interacts physically with Sox9 and is associated with Sox9 transcriptional activity via its nuclear translocation. A yeast two-hybrid screen using a cDNA library reveals that Wwp2 interacts with Med25, a component of the Mediator complex. The positive regulation of Sox9 transcriptional activity by Wwp2 is mediated by the binding between Sox9 and Med25. In zebrafish, morpholino-mediated knockdown of either wwp2 or med25 induces palatal malformation, which is comparable to that in sox9 mutants. These results provide evidence that the regulatory interaction between Sox9, Wwp2 and Med25 defines the Sox9 transcriptional mechanisms of chondrogenesis in the forming palate.

The enhancing rim fraction score, a quantitative DCE MR imaging lncRNA radiogenomic biomarker, is associated with early metastasis and expression of the known predictor of metastatic progression, HOTAIR.

The reduction effect of various carboxylic acids on inkjet-printed copper film was investigated. Carboxylic acids were exposed to the film by nitrogen gas that was bubbled through the liquid acids during the annealing process. It was observed that in the case of saturated monocarboxylic acid (formic, acetic, propionic, butyric), the acids with shorter hydrocarbon chains perform better in reducing the surface copper oxides in the printed copper conductive film. The printed films exposed to formic acid vapor exhibited the lowest resistivity (3.10 and 2.30 μΩ cm when annealed at 200 and 250 °C, respectively). In addition, the oxalic acid more effectively reduces copper oxide than formic acid and its usage can shorten the annealing time for highly conductive printed copper film. This reductive annealing process allows fabrication of copper patterns with low resistivity, (3.82 μΩ cm annealed at 250 °C) comparable to the resistivity of bulk copper.

Siderophores are small iron-binding molecules that are synthesized and secreted in the iron-free form by microorganisms. Saccharomyces cerevisiae takes up iron bound to siderophores by two separate systems, one of which requires the ARN family of sidero phore-iron transporters. Arn1p and Arn3p are expressed in endosome-like intracellular vesicles. Here we present evidence that, in the absence of its specific substrate, ferrichrome, Arn1p is sorted directly from the Golgi to the endosomal compartment and does not cycle to the plasma membrane. When cells are exposed to ferrichrome at low concentrations, Arn1p stably relocalizes to the plasma membrane. At higher concentrations of ferrichrome, Arn1p relocalizes to the plasma membrane and rapidly undergoes endocytosis. Plasma membrane localization of Arn1p occurs only in the presence of its specific substrate, and not in the presence of other siderophores. Despite expression of Arn1p on the plasma membrane, mutant strains with defects in endocytosis exhibit reduced uptake of ferrichrome-iron. Thus, siderophores influence the trafficking of the Arn transporters within the cell and this trafficking is important for transporter function.

Solution processing of earth-abundant Cu2ZnSn(S1-x,Sex)4 (CZTSSe) absorber materials is an attractive research area in the economical and large-scale deployment of photovoltaics. Here, a band-gap-graded CZTSSe thin-film solar cell with 7.1% efficiency was developed using non-toxic solvent-based ink without the involvement of complex particle synthesis, highly toxic solvents, or organic additives. Despite the high series resistance due to the presence of a thick Mo(S,Se)x layer and Zn(S,Se) aggregates, a high short-circuit current density (JSC) was generated. In addition, there was no significant difference in open circuit voltages (VOC) between CZTS (0.517 V) and CZTSSe (0.505–0.479 V) cells, despite a significant band gap change from 1.51 eV to 1.24 eV. The high JSC and less loss of VOC are attributed to the effect of band gap grading induced by Se grading in the CZTSSe absorber layer. Our environmentally benign ink approach will enable the realization of low-cost, large-area, high-efficiency thin-film solar cells.

Sox9 belongs to the family of Sry-related high-mobility group box transcription factors controlling cell fate, cell proliferation and differentiation in various tissues, including cartilage, testis, the central nervous system, kidney, and gastrointestine. Mice conditionally lacking Sox9 have revealed essential roles for Sox9 in these tissues. To gain further insight into the role of Sox9 in different tissues and at different stages of development, we have generated a transgenic mouse line to express Sox9 in a Cre recombinase-dependent manner. The construct contained the human cytomegalovirus enhancer and chicken β-actin promoter, and a floxed monomeric red fluorescence protein 1 (mRFP1) cassette to direct ubiquitous expression of mRFP1. Cre expression removed the mRFP1 gene, allowing expression of Sox9 and enhanced green fluorescent protein. Expectedly, overexpression of Sox9 in chondrocytes using Col2a1-Cre mice suppressed chondrocyte hypertrophy, and delayed terminal differentiation and subsequent ossification. Misexpression of Sox9 in hypertrophic chondrocytes using Col10a1-Cre knock-in mice also delayed terminal differentiation. This Sox9 conditional transgenic mouse line will be a valuable tool to uncover tissue-specific and developmental stage-specific functions of Sox9.