scholarly journals Expression of VAMP-2-like protein in kidney collecting duct intracellular vesicles. Colocalization with Aquaporin-2 water channels.

1995 ◽  
Vol 96 (4) ◽  
pp. 1834-1844 ◽  
Author(s):  
S Nielsen ◽  
D Marples ◽  
H Birn ◽  
M Mohtashami ◽  
N O Dalby ◽  
...  
Keyword(s):  
Collecting Duct ◽  
Water Channels ◽  
Kidney Collecting Duct ◽  
Aquaporin 2 ◽  
Intracellular Vesicles

scholarly journals A Role for VAMP8/Endobrevin in Surface Deployment of the Water Channel Aquaporin 2

2009 ◽  
Vol 30 (1) ◽  
pp. 333-343 ◽  
Author(s):  
Cheng-Chun Wang ◽  
Chee Peng Ng ◽  
Hong Shi ◽  
Hwee Chien Liew ◽  
Ke Guo ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Membrane Protein ◽  
Collecting Duct ◽  
Water Channel ◽  
Snare Proteins ◽  
Snare Protein ◽  
Aquaporin 2 ◽  
Duct Cells ◽  
Collecting Duct Cells ◽  
Intracellular Vesicles

ABSTRACT Vesicle-associated-membrane protein 8 (VAMP8) is highly expressed in the kidney, but the exact physiological and molecular functions executed by this v-SNARE protein in nephrons remain elusive. Here, we show that the depletion of VAMP8 in mice resulted in hydronephrosis. Furthermore, the level of the vasopressin-responsive water channel aquaporin 2 (AQP2) was increased by three- to fivefold in VAMP8-null mice. Forskolin and [desamino-Cys1, D-Arg8]-vasopressin (DDAVP)-induced AQP2 exocytosis was impaired in VAMP8-null collecting duct cells. VAMP8 was revealed to colocalize with AQP2 on intracellular vesicles and to interact with the plasma membrane t-SNARE proteins syntaxin4 and syntaxin3, suggesting that VAMP8 mediates the regulated fusion of AQP2-positive vesicles with the plasma membrane.

scholarly journals Apical endosomes isolated from kidney collecting duct principal cells lack subunits of the proton pumping ATPase.

1992 ◽  
Vol 119 (1) ◽  
pp. 111-122 ◽  
Author(s):  
I Sabolic ◽  
F Wuarin ◽  
L B Shi ◽  
A S Verkman ◽  
D A Ausiello ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Proton Pump ◽  
Transmembrane Domain ◽  
Collecting Duct ◽  
Water Channels ◽  
Proton Pumping ◽  
Apical Plasma Membrane ◽  
Principal Cells ◽  
Kidney Collecting Duct ◽  
Early Endosomes

Endocytic vesicles that are involved in the vasopressin-stimulated recycling of water channels to and from the apical membrane of kidney collecting duct principal cells were isolated from rat renal papilla by differential and Percoll density gradient centrifugation. Fluorescence quenching measurements showed that the isolated vesicles maintained a high, HgCl2-sensitive water permeability, consistent with the presence of vasopressin-sensitive water channels. They did not, however, exhibit ATP-dependent luminal acidification, nor any N-ethylmaleimide-sensitive ATPase activity, properties that are characteristic of most acidic endosomal compartments. Western blotting with specific antibodies showed that the 31- and 70-kD cytoplasmically oriented subunits of the vacuolar proton pump were not detectable in these apical endosomes from the papilla, whereas they were present in endosomes prepared in parallel from the cortex. In contrast, the 56-kD subunit of the proton pump was abundant in papillary endosomes, and was localized at the apical pole of principal cells by immunocytochemistry. Finally, an antibody that recognizes the 16-kD transmembrane subunit of oat tonoplast ATPase cross-reacted with a distinct 16-kD band in cortical endosomes, but no 16-kD band was detectable in endosomes from the papilla. This antibody also recognized a 16-kD band in affinity-purified H+ ATPase preparations from bovine kidney medulla. Therefore, early endosomes derived from the apical plasma membrane of collecting duct principal cells fail to acidify because they lack functionally important subunits of a vacuolar-type proton pumping ATPase, including the 16-kD transmembrane domain that serves as the proton-conducting channel, and the 70-kD cytoplasmic subunit that contains the ATPase catalytic site. This specialized, non-acidic early endosomal compartment appears to be involved primarily in the hormonally induced recycling of water channels to and from the apical plasma membrane of vasopressin-sensitive cells in the kidney collecting duct.

scholarly journals Decreased expression of AQP2 and AQP4 water channels and Na, K-ATPase in kidney collecting duct in AQP3 null mice

2005 ◽  
Vol 97 (10) ◽  
pp. 765-778 ◽  
Author(s):  
Soo Kim ◽  
Veronika Gresz ◽  
Aleksandra Rojek ◽  
Weidong Wang ◽  
A.S. Verkman ◽  
...  
Keyword(s):  
Collecting Duct ◽  
Water Channels ◽  
Kidney Collecting Duct

scholarly journals Water channels in the kidney collecting duct

1995 ◽  
Vol 48 (4) ◽  
pp. 1082-1087 ◽  
Author(s):  
Sei Sasaki ◽  
Kiyohide Fushimi ◽  
Kenichi Ishibashi ◽  
Fumiaki Marumo
Keyword(s):  
Collecting Duct ◽  
Water Channels ◽  
Kidney Collecting Duct

scholarly journals Endocytic vesicles from renal papilla which retrieve the vasopressin-sensitive water channel do not contain a functional H+ ATPase.

1990 ◽  
Vol 111 (2) ◽  
pp. 379-389 ◽  
Author(s):  
W I Lencer ◽  
A S Verkman ◽  
M A Arnaout ◽  
D A Ausiello ◽  
D Brown
Keyword(s):  
Plasma Membrane ◽  
Water Permeability ◽  
Collecting Duct ◽  
Water Channel ◽  
Water Channels ◽  
Proton Pumps ◽  
Principal Cells ◽  
Kidney Collecting Duct ◽  
Fluorescence Imaging Microscopy ◽  
Membrane Components

The water permeability of the kidney collecting duct epithelium is regulated by vasopressin (VP)-induced recycling of water channels between an intracellular vesicular compartment and the plasma membrane of principal cells. To test whether the water channels pass through an acidic endosomal compartment during the endocytic portion of this pathway, we measured ATP-dependent acidification of FITC-dextran-labeled endosomes in isolated microsomal fractions from different regions of Brattleboro rat kidneys. Both VP-deficient controls and rat treated with exogenous VP were examined. ATP-dependent acidification was not detectable in endosomes containing water channels from distal papilla (osmotic water permeability Pf = 0.038 +/- 0.004 cm/s). In contrast, the addition of ATP resulted in a strong acidification of renal cortical endosomes (pHmin = 5.8, initial rate = 0.18-0.25 pH U/s). Acidification of cortical endosomes was reversed with nigericin and strongly inhibited by N-ethyl-maleimide. Passive proton permeability was similar and low in both cortical and papillary endosomes from rats treated or not treated with VP. The fraction of labeled endosomes present in microsomal preparations was determined by fluorescence imaging microscopy of microsomes nonspecifically bound to poly-l-lysine-coated coverslips and was 25% in cortical preparations compared to 14% (+VP) and 9% (-VP) in papillary preparations. The fraction of cortical endosomes was enriched 1.5-fold by immunoabsorption to coverslips coated with mAbs against the bovine vacuolar proton pump. In contrast, the fraction of papillary endosomes was depleted more than twofold by immunoabsorption to identical coverslips. Finally, sections of distal papilla stained with antibodies against the lysosomal glycoprotein LGP120 showed that most of the entrapped FITC-dextran did not colocalize with this lysosomal protein. These results demonstrate that vesicles which internalize water channels in kidney collecting duct principal cells lack functional proton pumps, and do not deliver the bulk of their FITC-dextran content to lysosomes. The data suggest that the principal cell contains a specialized nonacidic apical endocytic compartment which functions primarily to recycle membrane components, including water channels, to the plasma membrane.

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