The effect of HMGB1 A box on lung injury in mice with acute pancreatitis

The objective of this study is to observe the effect of high-mobility group protein B1 A Box (HMGB1 A) box on lung injury in mice with acute pancreatitis and its effect on the level of high-mobility group protein B1 (HMGB1) in lung, to explore the mechanism. A total of 60 male Institute of Cancer Research mice were randomly divided into control group (n = 30) and treatment group (n = 30). Severe acute pancreatitis mice model was induced by 20% L-Arg intraperitoneal injection. The recombination HMGB1 A box was used in treatment after modeling. All the mice were killed under anesthesia at 24 and 48 h after the modeling injection. The level of HMGB1 and activity of myeloperoxidase (MPO) in lung were measured. The pathological changes of lung were observed. The level of HMGB1 in lung of A box treatment group decreased more significantly 24 h and 48 h after modeling compared with control group. The activity of MPO in lung of A box treatment group decreased more significantly 24 h after modeling compared with control group. The lung tissue pathologic score of A box treatment group decreased more significantly 48 h after modeling compared with control group. HMGB1 expression levels in the lungs were positively related to histological score of injured lung in acute pancreatitis. It indicates that HMGB1 A box is remarkably protective to lung injury induced by acute pancreatitis.     

Protein ubiquitination is regulated by phosphorylation. An in vitro study.

Protein ubiquitination has been implicated in ATP-dependent protein turnover and in a number of biological processes in eukaryotic cells. The ubiquitination activating enzyme, E1, and ubiquitin carrier protein, E2, are two essential enzymes in the protein ubiquitination machinery. Using purified E1 and E2 from rabbit reticulocytes and various protein kinases, which include cAMP-dependent protein kinase, protein kinase C, and protein tyrosine kinase, we demonstrated that E1 is phosphorylated by protein kinase C, with a stoichiometry of 0.65 mol of phosphate/mol of E1, and one of the E2 isoforms, E2(32kDa), is phosphorylated by protein tyrosine kinase to 2 eq of phosphate/mol of protein. Phosphorylation of E1 causes a 2-fold enhancement of its activity as monitored by ubiquitin-dependent ATP in equilibrium PPi exchange. When 1 eq of phosphate was incorporated into E2(32kDa), a 2.4-fold activation was also observed for its activity to catalyze the ubiquitination of histone H2A. The regulatory significance of this finding is discussed.     

Marker-assisted selection for two rust resistance genes in sunflower

In this study we report on the identification of molecular markers, OX20₆₀₀ and OO04₉₅₀, linked to the geneR _Adv in the proprietary inbred line P2. This gene confers resistance to most of the pathotypes of Puccinia helianthi identified in Australia. Analysis indicates these RAPD markers are linked to the resistance locus at 0.0 cM and 11 cM respectively. SCAR markers SCX20₆₀₀ and SCO04₉₅₀ derived from these two RAPD markers, and SCT06₉₅₀ derived from a previously reported RAPD marker linked at 4.5 cM from the R ₁ rust resistance gene were developed. SCX20₆₀₀ and SCO04₉₅₀ were linked at similar distances from their resistance locus as the RAPD markers. SCTO6₉₅₀ co-segregated completely with rust resistance. The robustness of the R ₁ SCAR marker was demonstrated through the amplification of the marker in a diverse range of sunflower germplasm considered to possess the R ₁ gene. The SCAR markers forR _Adv were not amplified in the sunflower rust differential set thereby supporting the contention that this is a novel resistance gene. They did amplify in a number of proprietary lines closely related to the line P2. This locus is under further investigation as it will be useful in our attempts to use molecular-assisted breeding to produce durable resistance in sunflower to P. helianthi.     

Rescue of odontogenesis in Dmp1-deficient mice by targeted re-expression of DMP1 reveals roles for DMP1 in early odontogenesis and dentin apposition in vivo

Dentin matrix protein 1 (DMP1) is expressed in both pulp and odontoblast cells and deletion of the Dmp1 gene leads to defects in odontogenesis and mineralization. The goals of this study were to examine how DMP1 controls dentin mineralization and odontogenesis in vivo. Fluorochrome labeling of dentin in Dmp1-null mice showed a diffuse labeling pattern with a 3-fold reduction in dentin appositional rate compared to controls. Deletion of DMP1 was also associated with abnormalities in the dentinal tubule system and delayed formation of the third molar. Unlike the mineralization defect in Vitamin D receptor-null mice, the mineralization defect in Dmp1-null mice was not rescued by a high calcium and phosphate diet, suggesting a different effect of DMP1 on mineralization. Re-expression of Dmp1 in early and late odontoblasts under control of the Col1a1 promoter rescued the defects in mineralization as well as the defects in the dentinal tubules and third molar development. In contrast, re-expression of Dmp1 in mature odontoblasts, using the Dspp promoter, produced only a partial rescue of the mineralization defects. These data suggest that DMP1 is a key regulator of odontoblast differentiation, formation of the dentin tubular system and mineralization and its expression is required in both early and late odontoblasts for normal odontogenesis to proceed.     

Taccasubosides A-D, four new steroidal glycosides from Tacca subflabellata

By analyzing the steroidal content of fresh whole plants of Tacca subflabellata (Taccaceae), we isolated one sapogenin and eight glycosides with four kinds of steroidal skeletons including four new glycosides, named taccasubosides A-D (1-4), together with five known compounds. Among them, compound 1 is the first pentacyclic sterol glycoside with 6-6-6-5-6 fused rings. The structures of 1-4 were elucidated on the basis of extensive spectroscopic analysis, including that of 2D NMR data, and the results of acidic hydrolysis. The cytotoxicity of the selected steroidal glycosides (1-4, 8, and 9) was evaluated in vitro against five human cancer cell lines. Compound 9 showed significant inhibitory activity against all five cell lines.     

Calcium prevents tumorigenesis in a mouse model of colorectal cancer

Background and Aim

Calcium has been proposed as a mediator of the chemoprevention of colorectal cancer (CRC), but the comprehensive mechanism underlying this preventive effect is not yet clear. Hence, we conducted this study to evaluate the possible roles and mechanisms of calcium-mediated prevention of CRC induced by 1,2-dimethylhydrazine (DMH) in mice.

Methods

For gene expression analysis, 6 non-tumor colorectal tissues of mice from the DMH + Calcium group and 3 samples each from the DMH and control groups were hybridized on a 4×44 K Agilent whole genome oligo microarray, and selected genes were validated by real-time polymerase chain reaction (PCR). Functional analysis of the microarray data was performed using KEGG and Gene Ontology (GO) analyses. Hub genes were identified using Pathway Studio software.

Results

The tumor incidence rates in the DMH and DMH + Calcium groups were 90% and 40%, respectively. Microarray gene expression analysis showed that S100a9, Defa20, Mmp10, Mmp7, Ptgs2, and Ang2 were among the most downregulated genes, whereas Per3, Tef, Rnf152, and Prdx6 were significantly upregulated in the DMH + Calcium group compared with the DMH group. Functional analysis showed that the Wnt, cell cycle, and arachidonic acid pathways were significantly downregulated in the DMH + Calcium group, and that the GO terms related to cell differentiation, cell cycle, proliferation, cell death, adhesion, and cell migration were significantly affected. Forkhead box M1 (FoxM1) and nuclear factor kappa-B (NF-κB) were considered as potent hub genes.

Conclusion

In the DMH-induced CRC mouse model, comprehensive mechanisms were involved with complex gene expression alterations encompassing many altered pathways and GO terms. However, how calcium regulates these events remains to be studied.     

Comparative genomics of the mating-type loci of the mushroom Flammulina velutipes reveals widespread synteny and recent inversions

Background

Mating-type loci of mushroom fungi contain master regulatory genes that control recognition between compatible nuclei, maintenance of compatible nuclei as heterokaryons, and fruiting body development. Regions near mating-type loci in fungi often show adapted recombination, facilitating the generation of novel mating types and reducing the production of self-compatible mating types. Compared to other fungi, mushroom fungi have complex mating-type systems, showing both loci with redundant function (subloci) and subloci with many alleles. The genomic organization of mating-type loci has been solved in very few mushroom species, which complicates proper interpretation of mating-type evolution and use of those genes in breeding programs.

Methodology/Principal Findings

We report a complete genetic structure of the mating-type loci from the tetrapolar, edible mushroom Flammulina velutipes mating type A3B3. Two matB3 subloci, matB3a that contains a unique pheromone and matB3b, were mapped 177 Kb apart on scaffold 1. The matA locus of F. velutipes contains three homeodomain genes distributed over 73 Kb distant matA3a and matA3b subloci. The conserved matA region in Agaricales approaches 350 Kb and contains conserved recombination hotspots showing major rearrangements in F. velutipes and Schizophyllum commune. Important evolutionary differences were indicated; separation of the matA subloci in F. velutipes was diverged from the Coprinopsis cinerea arrangement via two large inversions whereas separation in S. commune emerged through transposition of gene clusters.

Conclusions/Significance

In our study we determined that the Agaricales have very large scale synteny at matA (∼350 Kb) and that this synteny is maintained even when parts of this region are separated through chromosomal rearrangements. Four conserved recombination hotspots allow reshuffling of large fragments of this region. Next to this, it was revealed that large distance subloci can exist in matB as well. Finally, the genes that were linked to specific mating types will serve as molecular markers in breeding.     

Detection of Laribacter hongkongensis using species-specific duplex PCR assays targeting the 16S rRNA gene and the 16S-23S rRNA intergenic spacer region (ISR)

Aims: For the rapid detection of Laribacter hongkongensis, which is associated with human community‐acquired gastroenteritis and traveller’s diarrhoea, we developed a duplex species‐specific PCR assay. Methods and Results: Full‐length of the 16S–23S rRNA intergenic spacer region (ISR) sequences of 52 L. hongkongensis isolates were obtained by PCR‐based sequencing. Two species‐specific primer pairs targeting 16S rRNA gene and ISR were designed for duplex PCR detection of L. hongkongensis. The L. hongkongensis species‐specific duplex PCR assay showed 100% specificity, and the minimum detectable level was 2·1 × 10^?2 ng μl^?1 genomic DNA which corresponds to 5000 CFU ml^?1. Conclusions: The high specificity and sensitivity of the assay make it suitable for rapid detection of L. hongkongensis. Significance and Impact of the Study: This species‐specific duplex PCR method provides a rapid, simple, and reliable alternative to conventional methods to identify L. hongkongensis and may have applications in both clinical and environmental microbiology.     

提高CO2浓度对两种亚热带树苗生物量及叶片特性的影响

 广东鼎湖山季风常绿阔叶林的主要优势乔木树种荷木和黧蒴幼苗生长于自然光照和人工调节CO2浓度为500±50μl·L-1或空气CO2(350μl·L-1)的气罩中3个月。高CO2浓度下生长的黧蒴和荷木植株总干物质量分别增加26.6％和16.6%,根部增加量最大,地上部分所占的比例降低,根冠比上升,基径增大而株高降低。高CO2浓度下生长的叶片密度及比叶重增加,叶肉细胞间隙体积减少。单位干重的黧蒴叶片可溶性糖含量、全碳、磷、钾含量在高CO2浓度下稍为下降,果糖、葡萄糖、蔗糖、全氮、镁含量及N/C比明显降低。而全钙含量无明显变化。