The MTase15 regulates reproduction in the wing-dimorphic planthopper, Nilaparvata lugens (Hemiptera: Delphacidae).

S-Adenosyl-l-methionine-dependent methyltransferases (SAMMTases) modulate important cellular and metabolic activities in both prokaryotes and eukaryotes. Here, we functionally characterized an SAMMTase gene (MTase15) in the migratory brown planthopper (BPH), Nilaparvata lugens, which is the most notorious rice pest in Asia. The cDNA sequence of MTase15 is 2764 nt in length with an open reading frame of 1218 nt encoding 405 amino acid residues. Quantitative real-time PCR analysis showed that MTase15 was readily detected from egg to adult stages and extensively distributed in various body parts of adult females and males, with slightly high levels in ovary and testis, respectively. In addition, MTase15 was transcriptionally regulated by the insulin signalling pathway in BPH. RNA-interference-mediated knockdown of MTase15 (dsMtase15) resulted in deficiencies in vitellogenin synthesis and oogenesis, and female infertility. Males with Mtase15 knockdown retained the capability of producing sperms with normal viability, but less sperm was transferred to wild-type (wt) females during copulation, and eggs laid by these wt females arrested embryogenesis. These findings not only assign a functional role to MTase15, but also provide a link between the insulin signalling pathway and epigenetic regulation in BPH reproduction.

MiR-223 alleviates thrombus and inflammation in thromboangiitis obliterans rats by regulating NLRP3.

OBJECTIVE: The aim of this study was to observe the regulatory effects of micro ribonucleic acid (miR)-223 on thromboangiitis obliterans (TAO) rats, and to explore the potential regulatory mechanism. MATERIALS AND METHODS: Online database TargetScan was used to predict the downstream regulatory targets of miR-223. A total of 45 Sprague Dawley (SD) rats were randomly divided into three groups, including sham operation group (Sham group), Model group, and miR-223 agonist group (miR-223 mimic group). TAO model was successfully established in rats through the injection of lauric acid via the femoral artery. The content of serum thromboxane B2 (TXB2) and endothelin (ET) was measured via enzyme-linked immunosorbent assay (ELISA). The pathological changes in the left hind limb were detected via hematoxylin-eosin (HE) staining. Moreover, the expressions of interleukin-6 (IL-6) and IL-1ß in the tissues of the rat left hind limb were determined via immunohistochemistry. In addition, the protein expression of Nod-like receptor protein 3 (NLRP3) in tissues was determined using Western blotting. RESULTS: TargetScan database predicted that NLRP3 was the downstream target gene of miR-223. Compared with the Sham group, Model group exerted significantly higher content of serum TXB2 and ET, severe lesions in the rat left hind limb, as well as significantly increased expressions of IL-6 and IL-1ß and protein expression of NLRP3 in tissues of the rat left hind limb (p<0.05). Besides, compared with the Model group, miR-223 mimic group showed remarkably lower content of serum TXB2 and ET, improved lesions in the rat left hind limb, as well as decreased expressions of IL-6 and IL-1ß and protein expression of NLRP3 in the tissues of the rat left hind limb (p<0.05). CONCLUSIONS: MiR-223 agonist can alleviate thrombus and inflammatory response in TAO rats. The possible underlying mechanism may be related to targeted regulation on NLRP3 inflammasome expression.

Expression of pemphigus vulgaris antigen in cultured human keratinocytes: effect of inhibitors, tunicamycin, and lectins.

We have investigated expression of pemphigus vulgaris antigen(s) in cultured human keratinocytes induced by the addition of extracellular calcium. Cycloheximide (10(-4) M) inhibited pemphigus antigen expression and stratification but actinomycin D (2 micrograms/ml) had no effect. Tunicamycin, which inhibits dolichol pyrophosphate-mediated glycosylation of asparaginyl residues specifically, was used to study the role of glycosylation. When calcium switching was carried out in the presence of tunicamycin, human keratinocytes did not stratify, and the expression of pemphigus antigen was partially inhibited and limited to cell-cell contact areas. Analysis of biosynthetically labeled proteins showed that the synthesis of high-molecular-weight proteins was markedly reduced in the tunicamycin-treated cells. A reciprocal blocking test demonstrated that concanavalin A and wheat germ agglutinin receptor share an epitope with pemphigus vulgaris antigen(s). These results suggest that Ca++, newly synthesized protein, and N-asparaginyl glycosylation are required for normal pemphigus antigen expression and epidermal stratification in vitro. Pemphigus vulgaris antigen may have a highly glycosylated, high-molecular-weight protein chain with carbohydrates playing an important role in epidermal cell morphology, adhesion, and stability of cell surface antigens.

The particulate (speckled-like thread) nuclear staining pattern: species and cellular distribution of Ro/SSA antigen.

Anti-Ro/SSA antibodies are associated with a particulate (speckled-like thread) nuclear immunofluorescence (IF) staining pattern when human spleen imprints are employed as substrate. The present study was undertaken to determine if these antibodies would yield a similar IF pattern with splenic imprints from other species, and with other human cell lines. All splenic imprints (mammalian, avian, amphibian and fish origin) demonstrated a particulate nuclear pattern when treated with anti-Ro/SSA antibody positive serum samples. Cytospin preparations of a variety of peripheral blood cells also demonstrated this particulate pattern when treated with anti-Ro/SSA antibodies. Similar findings were noted when cytospin preparations of cultured keratinocyte cell lines were used as substrate. The antigen, associated with the particulate IF staining pattern when treated with anti-Ro/SSA antibody positive serum samples, is expressed in a variety of tissues and species.