SMURF1 Plays a role in EGF-induced breast cancer cell migration and invasion

Epidermal growth factor (EGF) is a well-known growth factor that induces cancer cell migration and invasion. Previous studies have shown that SMAD ubiquitination regulatory factor 1 (SMURF1), an E3 ubiquitin ligase, regulates cell motility by inducing RhoA degradation. Therefore, we examined the role of SMURF1 in EGF-induced cell migration and invasion using MDA-MB-231 cells, a human breast cancer cell line. EGF increased SMURF1 expression at both the mRNA and protein levels. All ErbB family members were expressed in MDA-MB-231 cells and receptor tyrosine kinase inhibitors specific for the EGF receptor (EGFR) or ErbB2 blocked the EGF-mediated induction of SMURF1 expression. Within the signaling pathways examined, ERK1/2 and protein kinase C activity were required for EGF-induced SMURF1 expression. The overexpression of constitutively active MEK1 increased the SMURF1 to levels similar to those induced by EGF. SMURF1 induction by EGF treatment or by the overexpression of MEK1 or SMURF1 resulted in enhanced cell migration and invasion, whereas SMURF1 knockdown suppressed EGF- or MEK1-induced cell migration and invasion. EGF treatment or SMURF1 overexpression decreased the endogenous RhoA protein levels. The overexpression of constitutively active RhoA prevented EGF- or SMURF1-induced cell migration and invasion. These results suggest that EGFinduced SMURF1 plays a role in breast cancer cell migration and invasion through the downregulation of RhoA.     

The role of lysyl oxidase-like 2 in the odontogenic differentiation of human dental pulp stem cells

Adult human dental pulp stem cells (hDPSCs) are a unique population of precursor cells those are isolated from postnatal dental pulp and have the ability to differentiate into a variety of cell types utilized for the formation of a reparative dentin-like complex. Using LC-MS/MS proteomics approaches, we identified the proteins secreted from the differentiating hDPSCs in mineralization media. Lysyl oxidase-like 2 (LOXL2) was identified as a protein that was down-regulated in the hDPSCs that differentiate into odontoblast-like cells. The role of LOXL2 has not been studied in dental pulp stem cells. LOXL2 mRNA levels were reduced in differentiating hDPSCs, whereas the levels of other LOX family members including LOX, LOXL1, LOXL3, and LOXL4, are increased. The protein expression and secretion levels of LOXL2 were also decreased during odontogenic differentiation. Recombinant LOXL2 protein treatment to hDPSCs resulted in a dose-dependent decrease in the early differentiation and the mineralization accompanying with the lower levels of odontogenic markers such as DSPP, DMP-1 and ALP. These results suggest that LOXL2 has a negative effect on the differentiation of hDPSCs and blocking LOXL2 can promote the hDPSC differentiation to odontoblasts.     

Pontibacter jeungdoensis sp. nov., isolated from a solar saltern in Korea

A Gram-staining-negative, rod-shaped and red-pigmented bacterial strain, HMD3125^T, was isolated from a solar saltern in Jeungdo, Republic of Korea. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD3125^T formed a lineage within the genus Pontibacter and was similar to Pontibacter salisaro (96.1%) and P. korlensis (95.3%). The major fatty acids of strain HMD3125^T were summed feature 4 (comprising iso-C_17:1 I and/or anteiso-C_17:1 B; 30.4%), iso-C_15:0 (20.4%) and iso-C_17:0 3OH (17.2%). The polar lipid profile of HMD3125^T consisted of the phosphatidylethanolamine, four unidentified polar lipids, unidentified phospholipid, unidentified aminolipid and unidentified aminophospholipid. Strain HMD3125^T contained MK-7 as the predominant menaquinone and sym-homospermidine as the major polyamine. The DNA G+C content of strain HMD3125^T was 45.6 mol%. Strain HMD3125^T assigned as a novel species in the genus Pontibacter, for which the name Pontibacter jeungdoensis sp. nov. is proposed. The type strain is HMD3125^T (=KCTC 23156^T =CECT 7710^T).     

Changes of butterfly communities after forest fire

Fires change the diversity and composition of insects in forest ecosystems. In the present study, we examined the change of butterfly communities after a fire including the increase of butterfly richness, grassland species, and generalist species, and more changed communities. Butterflies were surveyed for 5 years after the big Uljin fire in 2007. During each year, butterflies were counted monthly by the line transect method from April to October at two sites (burned vs. unburned, ~ 1.5 km routes). Specialist grassland species decreased in the year of the fire but generalist species did not increase significantly. Butterfly richness did not change but butterfly diversity decreased due to a sudden increase of a species, Polygonia c-aureum. The butterfly community in the year of the fire was different from those in later years, showing temporary change of community in the year of the fire. Species composition was significantly different between burned and unburned sites, but this phenomenon cannot be interpreted as an influence of fire due to highly variable species composition of local butterfly assemblages and the non-repetitive sampling site of the present study.     

Immunostimulating Effects of Extract of Acanthopanax sessiliflorus

As malfunction/absence of immune cells causes a variety of immunosuppressive disorders and chemical synthetic drugs for curing these diseases have many adverse effects, vigorous studies are being conducted. The Acanthopanax family has been used as traditional medicines for gastric ulcer, diabetes, etc. and culinary materials in East-South Asia. In this study, the immunostimulating properties of A. sessiliflorus were evaluated. A. sessiliflorus increased not only the splenocyte number but also immune-related cytokines such as TNF-α. However, it could not upregulate the expressions of IFN-γ and IL-2. A. sessiliflorus increased the swimming time, and comparison of organ weights relative to body weights for immune-related organs such as the spleen and thymus after a forced swim test showed that it could recover the spleen and thymus weights. It also increased the expression of TNF-α and slightly increased the concentration of IFN-γ but not IL-2. From the results, we concluded that as A. sessiliflorus has not only a host defense effect but also a stress-ameliorating property, further study it will be a promising material of immunostimulating material.     

Biosynthesis of capsinoid is controlled by the Pun1 locus in pepper

Pungency in pepper (Capsicum annuum L.) has unique characteristics due to the alkaloid compound group, capsaicinoids, which includes capsaicin. Although capsaicinoids have been proved to have pharmacological and physiological effects on human health, the application of capsaicinoids has been limited because of their pungency. Capsinoids found in non-pungent peppers share closely related structures with capsaicinoids and show similar biological effects. Previous studies demonstrated that mutations in the p-AMT gene were related to the production of capsinoids; however, the pathway of capsinoid synthesis has not yet been fully elucidated. In this study, we performed genetic analysis to determine the mechanism of capsinoid synthesis using a F6 recombinant inbred line population. In this population, the presence/absence of capsinoids co-segregated with the genotype of the Pun1 locus, without exception. In addition, we screened the patterns of capsinoid synthesis and the correlation between the Pun1 locus and capsinoid synthesis in p-AMT mutant accessions. In Capsicum germplasms, we selected amino-acid-substituted mutants in the PLP binding domain of the p-AMT gene. Capsinoids were not synthesized with the recessive pun1 gene, regardless of the p-AMT genotype, and no relationship was found between p-AMT mutant type and capsinoid content. We concluded that the Pun1 gene, which is responsible for capsaicinoid synthesis, also controls capsinoid synthesis.