Phosphatidylinositol 3-kinase/Akt signaling mediates interleukin-32alpha induction in human pancreatic periacinar myofibroblasts

Interleukin (IL)-32 is a recently described proinflammatory cytokine, characterized by the induction of nuclear factor (NF)-kappaB activation. We studied IL-32alpha expression in human pancreatic periacinar myofibroblasts, which play important roles in the regulation of extracellular matrix metabolism and inflammatory responses in the pancreas. IL-32alpha protein expression was evaluated by Western blot analyses, and IL-32alpha mRNA expression was analyzed by Northern blot and real-time PCR analyses. IL-32alpha mRNA was weakly expressed without a stimulus, and its expression was markedly enhanced by IL-1beta, IFN-gamma, and TNF-alpha. IL-1beta, IFN-gamma, and TNF-alpha enhanced intracellular accumulation of IL-32alpha protein, but IL-32alpha was not detected in supernatants. Each cytokine dose and time dependently induced IL-32alpha mRNA expression. An inhibitor of phosphatidylinositol 3-kinase (LY294002) significantly suppressed IL-1beta-, IFN-gamma-, and TNF-alpha-induced IL-32alpha mRNA expression, although MAPK inhibitors had no effect. Akt activation in response to these cytokines was confirmed by Western blot. Furthermore, LY294002 suppressed both IL-1beta- and TNF-alpha-induced NF-kappaB activation and IL-1beta-, TNF-alpha-, and IFN-gamma-induced activated protein-1 (AP-1) activation. Blockade of NF-kappaB and AP-1 activation by an adenovirus expressing a stable mutant form of IkappaBalpha and a dominant negative mutant of c-Jun markedly suppressed IL-1beta-, IFN-gamma-, and/or TNF-alpha-induced IL-32alpha mRNA expression. Human pancreatic periacinar myofibroblasts expressed IL-32alpha in response to IL-1beta, TNF-alpha, and IFN-gamma. IL-32alpha mRNA expression is dependent on interactions between the phosphatidylinositol 3-kinase/Akt-pathway and the NF-kappaB/AP-1 system.     

T2BP, a novel TRAF2 binding protein, can activate NF-kappaB and AP-1 without TNF stimulation.

TRAF2 is a key molecule involved in TNF signaling, which is crucial for the regulation of inflammatory processes. We have identified a novel TRAF2 binding protein, designated as T2BP (TRAF2 binding protein), by a mammalian two-hybrid screening approach. T2BP is a relatively small protein of 184 amino acids, which includes a forkhead-associated domain, the phosphopeptide binding motif. The interaction domain search showed that the TRAF domain in TRAF2 is required for the binding to T2BP whereas almost the entire protein in T2BP binds to TRAF2. The interaction was further confirmed by co-immunoprecipitation. Expression profiling for T2BP and TRAF2 revealed an ubiquitous expression in adult mouse tissues. Overexpression of T2BP in HEK293 cells activated NF-kappaB and AP-1 in a dose dependent manner as well as seen in the TNF-treated control cells. Our results suggest that T2BP is involved in the TNF-mediated signaling by its interaction with TRAF2.     

Reproducible Alterations of DNA Methylation at a Specific Population of CpG Islands during Blast Formation of Peripheral Blood Lymphocytes

We investigated the changes in the methylation patterns of CpGislands associated with blast formation of human peripheralblood lymphocytes activated by anti-CD3 and interleukin-2 (IL-2),using restriction landmark genomic scanning with a methylation-sensitiverestriction enzyme (RLGS-M) system. Of about 2,100 Not I spot/lociwhich were analyzed, only 10 showed changes, whereas drasticchanges have been observed in cases of malignant and SV40 transformation.These changes were highly reproducible for samples from boththe same and different individuals. Even the timing of the changesafter cultivation was the same. Thus, we concluded that at leastthe genomic DNA methylation state in vivo was essentially retainedin T blast cells activated in vitro by induction with IL-2 andanti-CD3, which are commonly used in biological experimentsas well as clinical diagnosis and therapy.     

Neonates' vocal and facial expressions and their changes during experimental playbacks of intra-uterine sounds

The present study was conducted to describe neonates' vocalizations and facial expressions in crying states, and to examine the effects of intra-uterine sounds on neonates' vocal and facial behaviors. Based on 22 h taped data taken from 4 healthy full-term neonates ranging in ages of 10–168 h, a total of 1020 samples of vocalization and their accompanying facial expressions were analyzed, and 12 categories of vocalizations and 8 categories of facial expressions were classified. In the playback experiments, it was shown that presentation of intra-uterine sounds changed the fundamental frequencies of infant cry vocalizations. Furthermore, it was found that the intra-uterine sounds elicited a progenitor of the facial expression of “affection” which mainly occurred accompanying the emission of short and low vocalizations.     

Mechanism of Action of Showdomycin

Showdomycin, 2-β-d-ribofuranosylmaleimide, inhibited the incorporation of amino acids and purine and pyrimidine bases into macromolecules in E. coli K-12 cells at low concentrations. The inhibitory action of showdomycin could be reversed by the addition of a nucleoside or a sulfhydryl compound. In marked contrast to common nucleosides, the pseudouridine showed no such effect. This may indicate that the N-glycosyl linkage in the nucleoside is a structural requirement for its reversing activity on the inhibitory action of showdomycin.

N-Ethylmaleimide, which has structural similarity to showdomycin, inhibited the incorporation of amino acids and purine and pyrimidine bases as well as showdomycin. The inhibitory action of N-ethylmaleimide, however, was not reversed by the addition of a nucleoside. This may indicate that there may be difference in the mechanism of the inhibitory action between N-ethylmaleimide and showdomycin.     

Inter- and intrapopulational variations in the peroxidase isozyme ofAsarum nipponicum F. Maekawa

Both the inter- and intrapopulational variations in five natural populations ofAsarum nipponicum F. Maekawa were demonstrated for peroxidase isozymes using gel electrofocusing. The patterns of isozymic variation suggested that a very short distance (100 m) effectively isolates populations. The reason why some bands were not detected in a particular population is discussed in terms of genetic drift.     

An epigenetic aberration increased in intergenic regions of cloned mice

The causes of frequent abnormal phenotypes and low success rate in mammalian cloning are poorly understood. Although epigenetic aberration is suspected to be a cause, its connection to the phenotypes has yet to be investigated. To measure the level of reprogramming of an epigenetic mark, acetylation at lysine 9 of histone H3 (H3K9Ac), in cloned mice, we examined its conservation between two cloned mice derived from distinct cell nuclei and their natural donors by utilizing whole-genome tiling arrays and quantitative PCR. Pairwise comparison of the H3K9Ac enrichment profile between the four mice revealed that H3K9Ac is less conserved in intergenic regions than in promoter regions of protein-coding genes. Intriguingly, the variation of H3K9Ac enrichment in intergenic regions is the most prominent in comparison of the two clones, possibly reflecting an additive effect of aberrant reprogramming of this epigenetic information occurring specifically in each of the two clones.

     

Clinico-molecular study of dedifferentiation in well-differentiated liposarcoma

Well-differentiated liposarcoma (WD) acquires fully malignant potential when the histological progression named dedifferentiation occurs. This progression is supposed to occur in a time-dependent manner but this is still a debated issue. Clinically, the prediction of dedifferentiation for WD is very important from the therapeutic point of view. To identify genes that are predictive of dedifferentiation and to understand the mechanism of dedifferentiation, we investigated clinical information of 50 cases and studied the gene expression profiles of 36 lipomatous tumors using cDNA microarray. The clinical study showed that the dedifferentiation did not always seem to occur in a time-dependent manner. Interestingly, from the gene expression study, unsupervised hierarchical clustering analysis of well-differentiated lesions obtained from dedifferentiated liposarcoma (DD) cases that were indistinguishable from WD pathologically showed a clearly distinct gene expression pattern from WD. Using the pattern-matching program, 1687 genes including 487 known genes were identified, which discriminated WD cases from well-differentiated lipomatous lesions obtained from DD cases. These results suggest that the dedifferentiation may arise from different types of WD that could be distinguished from gene expression profiling but could hardly be classified by the pathological studies.     

High-level expression and bulk crystallization of recombinant l-methionine γ-lyase, an anticancer agent

l-Methionine γ-lyase is a pyridoxal 5′-phosphate-dependent enzyme which has tumor selective anticancer activity. An efficient production process for the recombinant enzyme was constructed by using the overexpression plasmid in Escherichia coli, large-scale cultivation, and practical crystallization on an industrial scale. The plasmid was optimized with a promoter and the region of the ribosome-binding site. Plasmid pMGLTrc03, which has a trc promoter and a spacing of 12 nucleotides between the Shine-Dalgarno sequence and the ATG translation initiation codon, was selected as the most suitable plasmid. The transformants produced the enzyme, which intracellularly accumulated at 2.1 mg/ml as an active form and accounted for 43% of the total proteins in the soluble fraction by simple batch fermentation using a 500-l fermentor. The crystals were directly obtained from crude enzyme with 87% yield by a crystallization in the presence of 9.0% polyethylene glycol 6000, 3.6% ammonium sulfate, and 0.18 M sodium chloride using a 100-l crystallizer. After recrystallization, the enzyme was purified by anion-exchange column chromatography to remove endotoxins and by gel filtration for polishing. We prepared 600 g of purified enzyme with a low endotoxin content of sufficient quality for therapeutical use, with a 41% overall yield in the purification process.