Dynamics of quercetin formation in onion (Allium cepa L.) during vegetation

Onion bulbs (Allium cepa L.) are good sources of flavonoids. The aim of this study was to analyse the changes in dynamics of quercetin formation in three varieties of onions (white, yellow, and red) during the vegetation period. Quercetin content was determined after acid hydrolysis (1.2 M HCl in 50% aqueous methanol) by high-performance liquid chromatography (HPLC). The content of total phenolics was determined using Folin-Ciocalteu reagent (FCR) according to LACHMAN and co-workers (2003). The content of polyphenols in onion ranged from 2893 to 6052 mg kg–1 and the content of quercetin ranged from 52.44 to 280.72 mg kg–1 in fresh matter. The highest content of polyphenols and quercetin was found in the red variety. According to statistical analysis the dynamic of quercetin formation in all cultivars had statistically moderate (P<0.05) increasing tendency. Increasing content of polyphenols was accompanied with slight increase of quercetin, but the differences remained insignificant (P<0.05)

Distinct self-interaction domains promote Multi Sex Combs accumulation in and formation of the Drosophila

Nuclear bodies (NBs) are structures that concentrate proteins, RNAs, and ribonucleoproteins that perform functions essential to gene expression. How NBs assemble is not well understood. We studied the Drosophila histone locus body (HLB), a NB that concentrates factors required for histone mRNA biosynthesis at the replication-dependent histone gene locus. We coupled biochemical analysis with confocal imaging of both fixed and live tissues to demonstrate that the Drosophila Multi Sex Combs (Mxc) protein contains multiple domains necessary for HLB assembly. An important feature of this assembly process is the self-interaction of Mxc via two conserved N-terminal domains: a LisH domain and a novel self-interaction facilitator (SIF) domain immediately downstream of the LisH domain. Molecular modeling suggests that the LisH and SIF domains directly interact, and mutation of either the LisH or the SIF domain severely impairs Mxc function in vivo, resulting in reduced histone mRNA accumulation. A region of Mxc between amino acids 721 and 1481 is also necessary for HLB assembly independent of the LisH and SIF domains. Finally, the C-terminal 195 amino acids of Mxc are required for recruiting FLASH, an essential histone mRNA-processing factor, to the HLB. We conclude that multiple domains of the Mxc protein promote HLB assembly in order to concentrate factors required for histone mRNA biosynthesis

Chia seeds products: an overview

Chia, Salvia hispanica L., is a medicinal and dietary plant species used since ancient times by Mayan and Aztec. Its product is a dry indehiscent fruit which is commonly called seed. In recent times, there was an increasing attention and diffusion of the seeds of the plant for their health benefits and uses in cooking. In fact, seeds are a rich source of nutrients first of all the polyunsaturated omega-3 fatty acids that protect from inflammation, enhance cognitive performance and reduce the level of cholesterol. Seeds are also rich in polyphenols derived from caffeic acid that are antioxidant compounds protecting the body from free radicals, aging and cancer. In addition, carbohydrate based fibers, present at high concentration levels, are associated with reducing inflammation, lowering cholesterol and regulating bowel function. This review summarizes the current knowledge on the phytochemistry and pharmacological properties of the seeds of this plant, with special emphasis on the nutritional, and phytochemical analysis of the plant, including the recently developed metabolomic studie