The formation of type-I concretions in Drosophila Malpighian tubules studied by electron microscopy and X-ray microanalysis

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“…Glucose and other sugar transporters are consistently abundant and enriched, implying that sugar transport is a major (and previously unsuspected) role of the tubule. Inorganic transporters are also included in the table; there are also copper and zinc transporters, which is consistent with electron-probe X-ray microanalysis data that heavy metals accumulate in tubule concretions [38,39], and with the extreme abundance of metallothionein A (Table 1). …”

“…Malpighian tubules were dissected from 7-day-old adults, for compatibility with the extensive physiological literature on the tubule [10,11,13,15,17,19,20,39,70,75,94-96]. At this stage, the tubules are in a relatively stable state after adult emergence, and their secretion parameters do not change detectably between 3 and 14 days post-emergence.…”

NHE8 is an intracellular cation/H+exchanger in renal tubules of the yellow fever mosquitoAedes aegypti

“…Thus AeNHE8 could play an important role in a recycling pathway that maintains the integrity of proteins and organelles located in the brush border. Alternatively, AeNHE8 could contribute toward the regulation of pH in organelles (e.g., secretory vesicles) of principal cells that are involved with the latter stages of a basolateral-to-apical transcytotic pathway, such as those required for the excretion of xenobiotic compounds from the hemolymph (26,69,89) or for the secretion of mineralized concretions from within principal cells (82).…”

Transepithelial transport of fluorescent p-glycoprotein and MRP2 substrates by insect Malpighian tubules: confocal microscopic analysis of secreted fluid droplets

“…Wessing and Zierold, 1999) would confound both quantitative and qualitative analysis of dye accumulation in the tubule lumen, we developed a method for measuring the concentration of Texas Red, daunorubicin and other fluorochromes in the fluid secreted by MTs set up in Ramsay assays. Secreted fluid droplets were collected in optically flat glass capillaries, as described in the methods.…”