Collaborative environmental DNA sampling from petal surfaces of flowering cherry <Emphasis Type="Italic">Cerasus</Emphasis> × <Emphasis Type="Italic">yedoensis</Emphasis> ‘Somei-yoshino’ across the Japanese archipelago

Recent studies have shown that environmental DNA is found almost everywhere. Flower petal surfaces are an attractive tissue to use for investigation of the dispersal of environmental DNA in nature as they are isolated from the external environment until the bud opens and only then can the petal surface accumulate environmental DNA. Here, we performed a crowdsourced experiment, the “Ohanami Project”, to obtain environmental DNA samples from petal surfaces of Cerasus?×?yedoensis ‘Somei-yoshino’ across the Japanese archipelago during spring 2015. C. × yedoensis is the most popular garden cherry species in Japan and clones of this cultivar bloom simultaneously every spring. Data collection spanned almost every prefecture and totaled 577 DNA samples from 149 collaborators. Preliminary amplicon-sequencing analysis showed the rapid attachment of environmental DNA onto the petal surfaces. Notably, we found DNA of other common plant species in samples obtained from a wide distribution; this DNA likely originated from the pollen of the Japanese cedar. Our analysis supports our belief that petal surfaces after blossoming are a promising target to reveal the dynamics of environmental DNA in nature. The success of our experiment also shows that crowdsourced environmental DNA analyses have considerable value in ecological studies.     

Histone H3 peptides incorporating modified lysine residues as lysine-specific demethylase 1 inhibitors

Lysine-specific demethylase 1 (LSD1) is a flavin-dependent enzyme that removes methyl groups from mono- or dimethylated lysine residues at the fourth position of histone H3. We have previously reported several histone H3 peptides containing an LSD1 inactivator motif at Lys-4. In this study, histone H3 peptides having a trans-2-phenylcyclopropylamine (PCPA), a 2,5-dihydro-1H-pyrrole, and a 1,2,3,6-tetrahydropyridine moiety at Lys-4 were prepared along with related compounds possessing a shorter side chain at the fourth position. Enzymatic assays showed that PCPA peptides containing a longer side chain, which can react with FAD in the active site, are potent LSD1-selective inhibitors.     

sn-Glycerol-1-Phosphate-Forming Activities in Archaea: Separation of Archaeal Phospholipid Biosynthesis and Glycerol Catabolism by Glycerophosphate Enantiomers

In Methanobacterium thermoautotrophicum, sn-glycerol-1-phosphate (G-1-P) dehydrogenase is responsible for the formation of the Archaea-specific backbone of phospholipids, G-1-P, from dihydroxyacetonephosphate (DHAP). The possible G-1-P-forming activities were surveyed in cell-free extracts of six species of Archaea. All the archaeal cell-free homogenates tested revealed the ability to form G-1-P from DHAP. In addition, activities of G-3-P-forming glycerol kinase and G-3-P dehydrogenase were also detected in four heterotrophic archaea, while glycerol kinase activity was not detected in two autotrophic methanogens. These results show that G-1-P is produced from DHAP by G-1-P dehydrogenase in a wide variety of archaea while exogenous glycerol is catabolized via G-3-P.     

Dorsal hump morphology in pink salmon (Oncorhynchus gorbuscha)

Mature male Pacific salmon (Genus Oncorhynchus) develop a dorsal hump, as a secondary male sexual characteristic, during the spawning period. Previous gross anatomical studies have indicated that the dorsal humps of salmon are mainly composed of cartilaginous tissue (Davidson [1935] J Morphol 57:169–183.) However, the histological and biochemical characteristics of such humps are poorly understood. In this study, the detailed microstructures and components of the dorsal humps of pink salmon were analyzed using histochemical techniques and electrophoresis. In mature males, free interneural spines and neural spines were located in a line near to the median septum of the dorsal hump. No cartilaginous tissue was detected within the dorsal hump. Fibrous and mucous connective tissues were mainly found in three regions of the dorsal hump: i) the median septum, ii) the distal region, and iii) the crescent‐shaped region. Both the median septum and distal region consisted of connective tissue with a high water content, which contained elastic fibers and hyaluronic acid. It was also demonstrated that the lipid content of the dorsal hump connective tissue was markedly decreased in the mature males compared with the immature and maturing males. Although, the crescent‐shaped region of the hump consisted of connective tissue, it did not contain elastic fibers, hyaluronic acid, or lipids. In an ultrastructural examination, it was found that all of the connective tissues in the dorsal hump were composed of collagen fibers. Gel electrophoresis of collagen extracts from these tissues found that the collagen in the dorsal hump is composed of Type I collagen, as is the case in salmon skin. These results indicate that in male pink salmon the dorsal hump is formed as a result of an increase in the amount of connective tissue, rather than cartilage, and the growth of free interneural spines and neural spines. J. Morphol. 275:514–527, 2014. © 2013 Wiley Periodicals, Inc.     

Lysophosphatidylcholine Acyltransferase1 Overexpression Promotes Oral Squamous Cell Carcinoma Progression via Enhanced Biosynthesis of Platelet-Activating Factor

Background

The relevance of lysophosphatidylcholine acyltransferase1 (LPCAT1), a cytosolic enzyme in the remodeling pathway of phosphatidylcholine metabolism, in oral squamous cell carcinoma (OSCC) is unknown. We investigated LPCAT1 expression and its functional mechanism in OSCCs.

Methods

We analyzed LPCAT1 mRNA and protein expression levels in OSCC-derived cell lines. Immunohistochemistry was performed to identify correlations between LPCAT1 expression levels and primary OSCCs clinicopathological status. We established LPCAT1 knockdown models of the OSCC-derived cell lines (SAS, Ca9-22) for functional analysis and examined the association between LPCAT1 expression and the platelet-activating factor (PAF) concentration and PAF-receptor (PAFR) expression.

Results

LPCAT1 mRNA and protein were up-regulated significantly (p<0.05) in OSCC-derived cell lines compared with human normal oral keratinocytes. Immunohistochemistry showed significantly (p<0.05) elevated LPCAT1 expression in primary OSCCs compared with normal counterparts and a strong correlation between LPCAT1-positive OSCCs and tumoral size and regional lymph node metastasis. In LPCAT1 knockdown cells, cellular proliferation and invasiveness decreased significantly (p<0.05); cellular migration was inhibited compared with control cells. Down-regulation of LPCAT1 resulted in a decreased intercellular PAF concentration and PAFR expression.

Conclusion

LPCAT1 was overexpressed in OSCCs and correlated with cellular invasiveness and migration. LPCAT1 may contribute to tumoral growth and metastasis in oral cancer.     

Pathogen recognition by Toll-like receptor 2 activates Weibel-Palade body exocytosis in human aortic endothelial cells

The endothelial cell-specific granule Weibel-Palade body releases vasoactive substances capable of modulating vascular inflammation. Although innate recognition of pathogens by Toll-like receptors (TLRs) is thought to play a crucial role in promotion of inflammatory responses, the molecular basis for early-phase responses of endothelial cells to bacterial pathogens has not fully been understood. We here report that human aortic endothelial cells respond to bacterial lipoteichoic acid (LTA) and synthetic bacterial lipopeptides, but not lipopolysaccharide or peptidoglycan, to induce Weibel-Palade body exocytosis, accompanied by release or externalization of the storage components von Willebrand factor and P-selectin. LTA could activate rapid Weibel-Palade body exocytosis through a TLR2- and MyD88-dependent mechanism without de novo protein synthesis. This process was at least mediated through MyD88-dependent phosphorylation and activation of phospholipase Cgamma. Moreover, LTA activated interleukin-1 receptor-associated kinase-1-dependent delayed exocytosis with de novo protein synthesis and phospholipase Cgamma-dependent activation of the NF-kappaB pathway. Increased TLR2 expression by transfection or interferon-gamma treatment increased TLR2-mediated Weibel-Palade body exocytosis, whereas reduced TLR2 expression under laminar flow decreased the response. Thus, we propose a novel role for TLR2 in induction of a primary proinflammatory event in aortic endothelial cells through Weibel-Palade body exocytosis, which may be an important step for linking innate recognition of bacterial pathogens to vascular inflammation.