NF-Y recruitment of TFIID, multiple interactions with histone fold TAF(II)s

The nuclear factor y (NF-Y) trimer and TFIID contain histone fold subunits, and their binding to the CCAAT and Initiator elements of the major histocompatibility complex class II Ea promoter is required for transcriptional activation. Using agarose-electrophoretic mobility shift assay we found that NF-Y increases the affinity of holo-TFIID for Ea in a CCAAT- and Inr-dependent manner. We began to dissect the interplay between NF-Y- and TBP-associated factors PO1II (TAF(II)s)-containing histone fold domains in protein-protein interactions and transfections. hTAF(II)20, hTAF(II)28, and hTAF(II)18-hTAF(II)28 bind to the NF-Y B-NF-YC histone fold dimer; hTAF(II)80 and hTAF(II)31-hTAF(II)80 interact with the trimer but not with the NF-YB-NF-YC dimer. The histone fold alpha2 helix of hTAF(II)80 is not required for NF-Y association, as determined by interactions with the naturally occurring splice variant hTAF(II)80delta. Expression of hTAF(II)28 and hTAF(II)18 in mouse cells significantly and specifically reduced NF-Y activation in GAL4-based experiments, whereas hTAF,120 and hTAF(II)135 increased it. These results indicate that NF-Y (i) recruits purified holo-TFIID in vitro and (ii) can associate multiple TAF(II)s, potentially accommodating different core promoter architectures

Phosphorylation of silk fibroins improves the cytocompatibility of silk fibroin derived materials: a platform for the production of tuneable material

Silk fibroin demonstrates great biocompatibility and is suitable for many biomedical applications, including tissue engineering and regenerative medicine. Current research focuses on manipulating the physico-chemical properties of fibroin, and examining the effect of this manipulation on firobin's biocompatibility. Regenerated silk fibroin was modified by in vitro enzymatic phosphorylation and cast into films. Films were produced by blending, at several ratios, the phosphorylated and un-phosphorylated fibroin solutions. Fourier transform infra-red spectroscopy was used to determine the specific P–OH vibration peak, confirming the phosphorylation of the regenerated silk fibroin solution. Differential scanning calorimetry showed that phosphorylation altered the intra- and inter-molecular interactions. Further experiments demonstrated that phosphorylation can be used to tailor the hydrophylicity/hydrophobicity ratio as well as the crystalinity of silk fibroin films. Release profiling of a model drug was highly dependent on silk modification level. Cytotoxicity assays showed that exposure to lixiviates of phosphorylated films only slightly affected cellular metabolism and proliferation, although direct contact resulted in a strong direct correlation between phosphorylation level and cell proliferation. This new method for tuning silk biomaterials to obtain specific structural and biochemical features can be adapted for a wide range of applications. Phosphorylation of silk fibroins may be applied to improve the cytocompatibility of any silk-based device that is considered to be in contact with live animals or human tissues.The authors would like to acknowledge the support granted to the authors by European NOVO Project, contract no. FP7-HEALTH 2011-two-stage 278402

In vitro phosphorylation as tool for modification of silk and keratin fibrous materials

An overview is given of the recent work on in vitro enzymatic phosphorylation of silk fibroin and human hair keratin. Opposing to many chemical "conventional" approaches, enzymatic phosphorylation is in fact a mild reaction and the treatment falls within "green chemistry" approach. Silk and keratin are not phosphorylated in vivo, but in vitro. This enzyme-driven modification is a major technological breakthrough. Harsh chemical chemicals are avoided, and mild conditions make enzymatic phosphorylation a real "green chemistry" approach. The current communication presents a novel approach stating that enzyme phosphorylation may be used as a tool to modify the surface charge of biocompatible materials such as keratin and silk

TAFII105 mediates activation of anti-apoptotic genes by NF-kappaB.

The transcription factor NF-kappaB is important for expression of genes involved in immune responses, viral infections, cytokine signaling and stress. In addition NF-kappaB plays a crucial role in protecting cells from TNF-alpha-induced apoptotic stimuli, presumably by activating anti-apoptotic genes. Here we report that the sub-stoichiometric TFIID subunit TAFII105 is essential for activation of anti-apoptotic genes in response to TNF-alpha, serving as a transcriptional coactivator for NF-kappaB. The putative coactivator domain of TAFII105 interacts with the activation domain of the p65/RelA member of the NF-kappaB family, and further stimulates p65-induced transcription in human 293 cells. Moreover, inhibition of TAFII105 activity by overexpression of a dominant negative mutant of TAFII105 decreased NF-kappaB transcriptional activity and severely reduced cell survival in response to TNF-alpha. Similarly, expression of anti-sense TAFII105 RNA sensitized the cells to TNF-alpha cytotoxicity. These results suggest that TAFII105 is involved in activation of anti-apoptotic genes by NF-kappaB

Recent insights from scanning electron microscopic assessment of durable polymer-coated drug-eluting stents

Research on drug-eluting stents (DES) has had to be highly dynamic because of the rapid modification of stent platforms and coatings, and even the development of completely new stent designs and concepts. Through various mechanisms, coating irregularities of DES might contribute to some of the remaining problems of DES, such as (late) stent thrombosis and (side-branch) restenosis. This article sheds light on recent bench-top testing of DES coatings, providing an update on the latest examinations of DES coating morphology with scanning electron microscopy. It also reviews the different methods used to quantify DES coating irregularities, and proposes stepwise examination of coatings of both customary and novel DES. There is still a need to carefully assess novel DES with scanning electron microscopy in order to obtain data that may complement preclinical and clinical studies. Stent manufacturers have a responsibility to continuously monitor the quality of their products and generally strive to perfect their devices. In addition, independent, external assessment of DES coatings was shown to provide valuable data that permit meaningful comparisons of different DES types. Likewise, interventional cardiologists may use such complementary information from bench-side research as one of the pieces of evidence available to tailor therapy in clinical practic