Fatty Acid Desaturase Bmdesat5, Suppressed in the Salivary Glands by Domestication, is Involved in Regulation of Food Intake in Silkworms.

Understanding the evolutionary genetics of food intake regulation in domesticated animals has relevance to evolutionary biology, animal improvement, and obesity treatment. Here, we observed that the fatty acid desaturase gene (Bmdesat5), which regulates food intake, is suppressed in domesticated silkworms, but expressed in the salivary glands of the wild silkworm Bombyx mandarina. The content of its catalytic product, cis-vaccenic acid, was related to the expression levels of Bmdesat5 in the salivary glands of domesticated and wild silkworm strains. These two strains also showed significant differences in food intake. Using orally administering cis-vaccenic acid and transgenic-mediated overexpression, we verified that cis-vaccenic acid functions as a satiation signal, regulating food intake and growth in silkworms. Selection analysis showed that Bmdesat5 experienced selection, especially in the potential promoter, 5'-untranslated, and intron regions. This study highlights the importance of the decrement of satiety in silkworm domestication and provides new insights into the potential involvement of salivary glands in the regulation of satiety in animals, by acting as a supplement to gut-brain nutrient signaling.

Non-classical digestive lipase BmTGL selected by gene amplification reduces the effects of mulberry inhibitor during silkworm domestication.

Efficient utilization of dietary lipids is crucial for Bombyx mori, also known as domesticated silkworms. However, the effects of domestication on the genes encoding lipases remain unknown. In this study, we investigated the expression difference of one triacylglycerol lipase (BmTGL) between B.mori and wild (ancestor) silkworm strains (Bombyx mandarina). An immunofluorescence localization analysis showed that BmTGL was present in all parts of the gut and was released into the intestinal lumen. BmTGL expression was significantly enhanced in different domesticated silkworm strains compared to that in the B. mandarina strains. The BmTGL copy numbers in the genomes of the domesticated silkworm strains were 2-to-3 folds that of the B. mandarina strains and accounted for the enhanced expression of BmTGL in the domesticated silkworm strains. The Ser144Asn substitution in the Ser-Asp-His catalytic triads of BmTGL resulted in relatively lower lipase activity and reduced sensitivity to the lipase inhibitor morachalcone A. Moreover, BmTGL overexpression significantly increased the weights of the B. mori silkworms compared to those of the non-transgenic controls. Thus, the selection of BmTGL by gene amplification may be a trade-off between maintaining high enzymatic activity and reducing the effects of mulberry inhibitors during silkworm domestication.

[Simultaneous determination of rosmarinic acid, oridonin and chrysoplenetin in Isodon rubescens by HPLC].

An HPLC method was developed for simultaneous quantitation of rosmarinic acid, oridonin and chrysoplenetin in the aerial parts of Isodon rubescens. Samples were analyzed on an Ultimate C18 column (4.6 mm x 250 mm, 5 microm) with methanol and water containing 0.1% formic acid as mobile phases in a linear gradient mode. The flow rate was 1.0 mL x min(-1) and the temperature was set at 30 degrees C. The PDA detector wavelengths were set at 338 nm for rosmarinic and chrysoplenetin and at 242 nm for oridonin. The linear ranges were 0.222-2.78, 0.227-2.84 and 0.005-0.071 microg for rosmarinic acid, oridonin and chrysoplenetin, respectively. The average recoveries of the three constituents were 102.9% (RSD 1.9%), 99.6% (RSD 1.1%) and 102.5% (RSD 0.94%), respectively. This method was proved to be accurate and repeatable, and can be used for quality control of the aerial parts of I. rubescens.

[Chemical constituents from fungus Armillaria mellea].

Ten compounds were isolated from cultures of the fungus Armillaria mellea by silica gel and Sephadex LH-20 column chromatographies. Their structures were identified by spectroscopic data analysis and compared their spectroscopic data with those reported in the literature as 2-hydroxy-4-methoxy-6-methylbenzoic acid (1), orsellinic acid (2), melleolide (3), ergosterol (4), genistein (5), daidzein (6), daucosterol (7), genistin (8), uracil (9) and D-mannitol (10). Compounds 1-10 were isolated from cultures of A. mellea for the first time. Among them, 14, 6 and 10 had been obtained from mycelia or rhizomorphs of A. mellea. The structure of compound 3 was determined by detailed analysis of its 1D and 2D NMR data in the solvent of DMSO for the first time.