Insight into the B3Transcription Factor Superfamily and Expression Profiling of B3 Genes in Axillary Buds after Topping in Tobacco(Nicotiana tabacum L.).

Members of the plant-specific B3 transcription factor superfamily play important roles in various growth and developmental processes in plants. Even though there are many valuable studies on B3 genes in other species, little is known about the B3 superfamily in tobacco. We identified 114 B3 proteins from tobacco using comparative genome analysis. These proteins were classified into four subfamilies based on their phylogenetic relationships, and include the ARF, RAV, LAV, and REM subfamilies. The chromosomal locations, gene structures, conserved protein motifs, and sub-cellular localizations of the tobacco B3 proteins were analyzed. The patterns of exon-intron numbers and arrangement and the protein structures of the tobacco B3 proteins were in general agreement with their phylogenetic relationships. The expression patterns of 114 B3 genes revealed that many B3 genes show tissue-specific expression. The expression levels of B3 genes in axillary buds after topping showed that the REM genes are mainly up-regulated in response to topping, while the ARF genes are down-regulated after topping.

Wild chrysanthemum extract prevents UVB radiation-induced acute cell death and photoaging.

Wild chrysanthemum (Chrysanthemum indicum L.) is traditionally used in folk medicine as an anti-inflammatory agent. It is also used in the southwest plateau region of China to prevent ultraviolet-induced skin damage. However, the role and mechanism by which wild chrysanthemum prevents UV-induced skin damage and photoaging have never been investigated in vitro. In the present study, we found that aqueous extracts from wild chrysanthemum strongly reduced high-dose UVB-induced acute cell death of human immortalized keratinocytic HaCat cells. Wild chrysanthemum extract was also demonstrated to reduce low-dose UVB-induced expression of the photoaging-related matrix metalloproteinases MMP-2 and MMP-9. The ROS level elevated by UVB irradiation was strongly attenuated by wild chrysanthemum extract. Further study revealed that wild chrysanthemum extract reduced UVB-triggered ERK1/2 and p38 MAPK phosphorylation and their protective role, which is partially dependent on inhibiting p38 activation. These results suggest that wild chrysanthemum extract can protect the skin from UVB-induced acute skin damage and photoaging by reducing the intracellular reactive oxygen species (ROS) level and inhibiting p38 MAPK phosphorylation. The present study confirmed the protective role of wild chrysanthemum against UV-induced skin disorders in vitro and indicated the possible mechanism. Further study to identify the active components in wild chrysanthemum extract would be useful for developing new drugs for preventing and treating skin diseases, including skin cancer and photoaging, induced by UV irradiation.

The ubiquitin ligase RNF220 enhances canonical Wnt signaling through USP7-mediated deubiquitination of ß-catenin.

Wnt/ß-catenin signaling plays critical roles in embryonic development and disease. Here, we identify RNF220, a RING domain E3 ubiquitin ligase, as a new regulator of ß-catenin. RNF220 physically interacts with ß-catenin, but instead of promoting its ubiquitination and proteasomal degradation, it stabilizes ß-catenin and promotes canonical Wnt signaling. Our analysis showed that RNF220 interacts with USP7, a ubiquitin-specific peptidase, which is required for RNF220 to stabilize ß-catenin. The RNF220/USP7 complex deubiquitinates ß-catenin and enhances canonical Wnt signaling. Interestingly, the stability of RNF220 itself is negatively regulated by Gsk3ß, which is a key component of the ß-catenin destruction complex and is inhibited upon Wnt stimulation. Accordingly, the RNF220/USP7 complex works as a positive feedback regulator of ß-catenin signaling. In colon cancer cells with stimulated Wnt signaling, knockdown of RNF220 or USP7 impairs Wnt signaling and expression of Wnt target genes, suggesting a potentially novel role of RNF220 in Wnt-related tumorigenesis.

Transplanted human umbilical cord mesenchymal stem cells facilitate lesion repair in B6.Fas mice.

BACKGROUND: Systemic lupus erythematosus (SLE) is a multisystem disease that is characterized by the appearance of serum autoantibodies. No effective treatment for SLE currently exists. METHODS: We used human umbilical cord mesenchymal stem cell (H-UC-MSC) transplantation to treat B6.Fas mice. RESULTS: After four rounds of cell transplantation, we observed a statistically significant decrease in the levels of mouse anti-nuclear, anti-histone, and anti-double-stranded DNA antibodies in transplanted mice compared with controls. The percentage of CD4(+)CD25(+)Foxp3(+) T cells in mouse peripheral blood significantly increased after H-UC-MSC transplantation. CONCLUSIONS: The results showed that H-UC-MSCs could repair lesions in B6.Fas mice such that all of the relevant disease indicators in B6.Fas mice were restored to the levels observed in normal C57BL/6 mice.

SOCS3 inhibits insulin signaling in porcine primary adipocytes.

Insulin resistance is a major player in the pathogenesis of type II diabetes, the metabolic syndrome, and obesity. SOCS3 plays an important role in the development of insulin resistance. To investigate the role of SOCS3 in porcine adipocyte insulin signaling, we first detected the effect of insulin on SOCS3 mRNA and protein expression in porcine primary adipocytes by real-time RT-PCR and Western blotting. Then, we constructed a recombinant adenovirus encoding SOCS3 gene (Ad-SOCS3) which was used to infect differentiated porcine primary adipocytes for 3 days. The expression and phosphorylation of main insulin signaling components were detected by Western blotting. The results showed that 100 nM insulin could induce SOCS3 mRNA expression but not protein expression, and overexpression of SOCS3 decreased IRS1 protein level, insulin-stimulated IRS1 tyrosine phosphorylation, PI3K activation, and Akt phosphorylation, but increased IRS1 serine phosphorylation in porcine primary adipocytes. These results indicate that SOCS3 is an important negative regulator of insulin signaling in porcine adipocytes. Thus, SOCS3 may be a novel therapeutic target for the prevention or treatment of insulin resistance and type II diabetes.

[Construction of SOCS3 recombinant adenovirus and its expression in porcine primary adipocytes].

In order to construct recombinant adenovirus vector expressing Suppressor of cytokine signaling 3 (SOCS3) and obtain infectious adenoviral particles, SOCS3 gene was amplified from plasmid pcDNA3-SOCS3 and subcloned into the adenovirus shuttle plasmid pAdTrack-CMV. After sequence confirmation, the recombinant shuttle plasmid pAdTrack-CMV-SOCS3 was linearized by Pme I, and then transformed into BJ5183 competent cell, the recombinant plasmid pAd-SOCS3 was obtained by homologous recombination between pAdTrack-CMV-SOCS3 and the adenoviral backbone plasmid pAdEasy-1 in BJ5183. The pAd-SOCS3 was linearized by Pac I and transfected into HEK293 cells via liposome. The recombinant adenovirus was packaged and amplified in HEK293 cells. After purifying, virus titer was determined by tissue culture infectious dose 50 (TCID50). Using the recombinant adenoviruses to infect porcine primary adipocytes, the expression of green fluorescent protein (GFP) was observed by fluorescent microscopy, and SOCS3 gene was identified by RT-PCR and Western blotting. Restriction enzyme and PCR analysis demonstrated that the recombinant adenovirus vector was constructed correctly, and the virus titer reached 1.2x10(9) PFU/mL. The result of RT-PCR and Western blotting showed that SOCS3 mRNA and protein expression was remarkably increased in porcine primary adipocytes infected with recombinant adenovirus. In conclusion, this study successfully constructed the recombinant adenovirus containing SOCS3 gene, and can be helpful for further research on the function of SOCS3.