Journal: American Journal of Physiology - Renal Physiology

Article Title: WNK bodies cluster WNK4 and SPAK/OSR1 to promote NCC activation in hypokalemia

doi: 10.1152/ajprenal.00232.2019

Figure Lengend Snippet: Subcellular localization of with no lysine (WNK) bodies within distal convoluted tubule (DCT) cells. All images are of mice fed a high-salt (HS)/low-K+ (LK) diet for 10 days (n = 5, all male mice). OSR1, oxidative stress-responsive kinase-1; SPK, Ste20-related proline-alanine-rich kinase; pS-SPAK/OSR1, SPAK/OSR1 phosphorylated at Ser383/325. A: electron micrograph of epoxy resin-embedded tissue. The representative, hypodense WNK body (*) next to the nuclear membrane (nm) is not membrane bound and borders on endoplasmic reticulum (er) profiles. B: WNK bodies, here immunostained for WNK4, were located alongside microtubules visualized by β-tubulin immunofluorescence. C: WNK bodies, here immunostained for SPAK, were typically located near Golgi dictyosomes visualized by Gm130 immunofluorescence. D: WNK bodies, here immunostained for pS-SPAK/OSR1, were not colocalized with smaller cytoplasmic puncta containing proteasomal 20S subunit-immunoreactive signal. In B and C, conventional confocal overviews are on the left and stimulated emission depletion superresolution fluorescence micrographs of insets are on the right. D: conventional confocal micrograph.

Article Snippet: In labelings prepared for stimulated emission depletion (STED) microscopy, fluorescently labeled secondary antibodies (Abberior, Göttingen, Germany) were incubated for 2.5 h. Samples were mounted in 1:9 PBS-glycerol for confocal microscopy or in Abberior Mount Liquid Antifade for STED microscopy.

Techniques: Membrane, Immunofluorescence, Fluorescence