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551.
Massimo Aureli Maura Samarani Nicoletta Loberto Elena Chiricozzi Laura Mauri Sara Grassi Domitilla Schiumarini Alessandro Prinetti Sandro Sonnino 《Glycoconjugate journal》2018,35(4):397-402
Sphingolipid metabolism is an intricate network of several interdependent and co-regulated pathways. In addition to the mainstream biosynthetic and catabolic pathways, several processes, even if less important in contributing to the final tissue sphingolipid composition from the quantitative point of view, might become relevant when sphingolipid metabolism is for any reason dysregulated and concur to the onset of neuronal pathologies. The main subcellular sites involved in the mainstream metabolic pathway are represented by the Golgi apparatus (for the biosynthesis) and by the lysosomes (for catabolism). On the other hand, the minor collateral pathways are associated with the plasma membrane and membranes of other organelles, and likely play important roles in the local regulation of membrane dynamics and contribute to maintain a perfect membrane organization functional to the physiology of the cell. In this review, we will consider few aspects of the sphingolipid metabolic pathway depending by the dynamic of the membranes that seems to become relevant in neurodegenerative diseases. 相似文献
552.
Silas P. Rodrigues Maura Da Cunha José A. Ventura Patricia Machado Bueno Fernandes 《Plant cell reports》2009,28(5):861-871
Spontaneous latex exudation is the main symptom of papaya sticky (meleira) disease caused by the Papaya meleira virus (PMeV), a double-stranded RNA (dsRNA) virus. This paper describes different effects of PMeV on papaya latex. Latex samples
were subjected to different histochemical tests to evaluate their chemical composition. Additionally, the integrity of the
latex particles was assessed by transmission and scanning electron microscopy analysis. Biochemical and micro- and macro-element
measurements were performed. PMeV dsRNA extraction was performed to evaluate the interaction of the virus with the latex particles.
Sticky diseased latex was positive for alkaloid biosynthesis and showed an accumulation of calcium oxalate crystals. PMeV
also increased H2O2 synthesis within sticky diseased laticifers. The protein, sugar and water levels were altered, probably due to chemical changes.
The morphology of the latex particles was further altered; PMeV particles seemed to be bound to the latex particles. The alkaloid
and H2O2 biosynthesis in the papaya laticifers indicate a papaya defense response against PMeV. However, such efforts failed, as the
virus affected the plant latex. The effects described here suggest some advantages of the infection process, including facilitating
the movement of the virus within the papaya plant. 相似文献
553.
Kathlyn Vasconcelos Gevú Maura Da Cunha Claudia Franca Barros Sabrina Magna Pereira Helena Regina Pinto Lima 《Plant Systematics and Evolution》2014,300(5):1089-1098
Xylem structural characteristics are rarely used to separate tribes. This study aims to characterize the morphology of subterranean organs and determine both the occurrence and distribution of the vessel elements in ten species, belonging to Alpinieae and Zingibereae tribes. Species were from protected areas in the Brazilian Atlantic Rain Forest or from private cultivation areas. Roots and rhizomes processing followed both light and scanning electron microscopy procedures. According to morphological and anatomical characteristics, Euclidean distances among taxa were calculated, resulting in a dendrogram based on the unweighted pair group method with arithmetic mean (UPGMA) clustering. Despite our results indicating a similarity among all the species studied, they could be segregated by using qualitative and special metabolites characters in both the rhizome and the root. Vessel elements were found to be confined to the roots, presenting several basal characters in most of species, except for Alpinia purpurata and Etlingera species. 相似文献