Major Vault Protein Regulates Class A Scavenger Receptor-mediated Tumor Necrosis Factor-α Synthesis and Apoptosis in Macrophages

Atherosclerosis is considered a disease of chronic inflammation largely initiated and perpetuated by macrophage-dependent synthesis and release of pro-inflammatory mediators. Class A scavenger receptor (SR-A) expressed on macrophages plays a key role in this process. However, how SR-A-mediated pro-inflammatory response is modulated in macrophages remains ill defined. Here through immunoprecipitation coupled with mass spectrometry, we reported major vault protein (MVP) as a novel binding partner for SR-A. The interaction between SR-A and MVP was confirmed by immunofluorescence staining and chemical cross-linking assay. Treatment of macrophages with fucoidan, a SR-A ligand, led to a marked increase in TNF-α production, which was attenuated by MVP depletion. Further analysis revealed that SR-A stimulated TNF-α synthesis in macrophages via the caveolin- instead of clathrin-mediated endocytic pathway linked to p38 and JNK, but not ERK, signaling pathways. Importantly, fucoidan invoked an enrichment of MVP in lipid raft, a caveolin-reliant membrane structure, and enhanced the interaction among SR-A, caveolin, and MVP. Finally, we demonstrated that MVP elimination ameliorated SR-A-mediated apoptosis in macrophages. As such, MVP may fine-tune SR-A activity in macrophages which contributes to the development of atherosclerosis.     

A novel locus essential for spreading of Cytophaga hutchinsonii colonies on agar

Cytophaga hutchinsonii is an aerobic cellulolytic gliding bacterium. The mechanism of its cell motility over surfaces without flagella and type IV pili is not known. In this study, mariner-based transposon mutagenesis was used to identify a new locus CHU_1797 essential for colony spreading on both hard and soft agar surfaces through gliding. CHU_1797 encodes a putative outer membrane protein of 348 amino acids with unknown function, and proteins which have high sequence similarity to CHU_1797 were widespread in the members of the phylum Bacteroidetes. The disruption of CHU_1797 suppressed spreading toward glucose on an agar surface, but had no significant effect on cellulose degradation for cells already in contact with cellulose. SEM observation showed that the mutant cells also regularly arranged on the surface of cellulose fiber similar with that of the wild type strain. These results indicated that the colony spreading ability on agar surfaces was not required for cellulose degradation by C. hutchinsonii. This was the first study focused on the relationship between cell motility and cellulose degradation of C. hutchinsonii.     

Effects of Commercial Harvesting on Population Characteristics and Rhizome Yield of Anemone altaica

Effects of Commercial Harvesting on Population Characteristics and Rhizome Yield of Anemone altaica. Commercial harvesting constitutes a direct threat to numerous non–timber forest products (NTFPs), but its ecological effects have not been well documented. Anemone altaica Fisch. ex C. A. Mey, a spring ephemeral plant found in temperate forests of Eurasia, is a traditional Chinese herb. Owing to medicinal value, its rhizomes have been harvested for commercial purposes in northwestern China for many years. This paper addresses the ecological effects of commercial harvesting on A. altaica populations under different harvest intensities. The results show that size–selective harvesting of rhizomes can increase population densities by asexual propagation. Currently, two– to three–year–old individuals derived from asexual propagation are the main targets of commercial harvesting. The increased demand in recent years has resulted in earlier and more intensive harvesting activities largely impacting the natural recovery of the harvested populations. For sustainable use of this traditional medicinal species, we recommend that a periodic harvest strategy of three to four years be adopted.     

ZmGA3ox2, a candidate gene for a major QTL,qPH3.1, for plant height in maize

Maize plant height is closely associated with biomass, lodging resistance and grain yield. Determining the genetic basis of plant height by characterizing and cloning plant height genes will guide the genetic improvement of crops. In this study, a quantitative trait locus (QTL) for plant height, qPH3.1, was identified on chromosome 3 using populations derived from a cross between Zong3 and its chromosome segment substitution line, SL15. The plant height of the two lines was obviously different, and application of exogenous gibberellin A₃ removed this difference. QTL mapping placed qPH3.1 within a 4.0 cM interval, explaining 32.3% of the phenotypic variance. Furthermore, eight homozygous segmental isolines (SILs) developed from two larger F₂ populations further narrowed down qPH3.1 to within a 12.6 kb interval. ZmGA3ox2, an ortholog of OsGA3ox2, which encodes a GA3 β‐hydroxylase, was positionally cloned. Association mapping identified two polymorphisms in ZmGA3ox2 that were significantly associated with plant height across two experiments. Quantitative RT‐PCR showed that SL15 had higher ZmGA3ox2 expression relative to Zong3. The resultant higher GA₁ accumulation led to longer internodes in SL15 because of increased cell lengths. Moreover, a large deletion in the coding region of ZmGA3ox2 is responsible for the dwarf mutant d1‐6016. The successfully isolated qPH3.1 enriches our knowledge on the genetic basis of plant height in maize, and provides an opportunity for improvement of plant architecture in maize breeding.     

Radiolytic transformation of rotenone with potential anti-adipogenic activity

Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone.     

Pulmonary Tuberculosis Incidence and Risk Factors in Rural Areas of China: A Cohort Study

The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies.