scholarly journals Rab10 Regulates Membrane Transport through Early Endosomes of Polarized Madin-Darby Canine Kidney Cells

2006 ◽  
Vol 17 (7) ◽  
pp. 3156-3175 ◽  
Author(s):  
Clifford M. Babbey ◽  
Nahid Ahktar ◽  
Exing Wang ◽  
Carlos Chih-Hsiung Chen ◽  
Barth D. Grant ◽  
...  

Rab10, a protein originally isolated from Madin-Darby Canine Kidney (MDCK) epithelial cells, belongs to a family of Rab proteins that includes Rab8 and Rab13. Although both Rab8 and Rab13 have been found to mediate polarized membrane transport, the function of Rab10 in mammalian cells has not yet been established. We have used quantitative confocal microscopy of polarized MDCK cells expressing GFP chimeras of wild-type and mutant forms of Rab10 to analyze the function of Rab10 in polarized cells. These studies demonstrate that Rab10 is specifically associated with the common endosomes of MDCK cells, accessible to endocytic probes internalized from either the apical or basolateral plasma membrane domains. Expression of mutant Rab10 defective for either GTP hydrolysis or GTP binding increased recycling from early compartments on the basolateral endocytic pathway without affecting recycling from later compartments or the apical recycling pathway. These results suggest that Rab10 mediates transport from basolateral sorting endosomes to common endosomes.

1998 ◽  
Vol 9 (9) ◽  
pp. 2477-2490 ◽  
Author(s):  
Jennifer R. Henkel ◽  
Gerard Apodaca ◽  
Yoram Altschuler ◽  
Stephen Hardy ◽  
Ora A. Weisz

The function of acidification along the endocytic pathway is not well understood, in part because the perturbants used to modify compartmental pH have global effects and in some cases alter cytoplasmic pH. We have used a new approach to study the effect of pH perturbation on postendocytic traffic in polarized Madin–Darby canine kidney (MDCK) cells. Influenza M2 is a small membrane protein that functions as an acid-activated ion channel and can elevate the pH of the trans-Golgi network and endosomes. We used recombinant adenoviruses to express the M2 protein of influenza virus in polarized MDCK cells stably transfected with the polymeric immunoglobulin (Ig) receptor. Using indirect immunofluorescence and immunoelectron microscopy, M2 was found to be concentrated at the apical plasma membrane and in subapical vesicles; intracellular M2 colocalized partly with internalized IgA in apical recycling endosomes as well as with the trans-Golgi network marker TGN-38. Expression of M2 slowed the rate of IgA transcytosis across polarized MDCK monolayers. The delay in transport occurred after IgA reached the apical recycling endosome, consistent with the localization of intracellular M2. Apical recycling of IgA was also slowed in the presence of M2, whereas basolateral recycling of transferrin and degradation of IgA were unaffected. By contrast, ammonium chloride affected both apical IgA and basolateral transferrin release. Together, our data suggest that M2 expression selectively perturbs acidification in compartments involved in apical delivery without disrupting other postendocytic transport steps.


1997 ◽  
Vol 137 (6) ◽  
pp. 1255-1264 ◽  
Author(s):  
Greg Odorizzi ◽  
Ian S. Trowbridge

In polarized Madin-Darby canine kidney (MDCK) cells, the transferrin receptor (TR) is selectively delivered to the basolateral surface, where it internalizes transferrin via clathrin-coated pits and recycles back to the basolateral border. Mutant tailless receptors are sorted randomly in both the biosynthetic and endocytic pathways, indicating that the basolateral sorting of TR is dependent upon a signal located within the 61–amino acid cytoplasmic domain. To identify the basolateral sorting signal of TR, we have analyzed a series of mutant human TR expressed in MDCK cells. We find that residues 19–41 are sufficient for basolateral sorting from both the biosynthetic and endocytic pathways and that this is the only region of the TR cytoplasmic tail containing basolateral sorting information. The basolateral sorting signal is distinct from the YTRF internalization signal contained within this region and is not tyrosine based. Detailed functional analyses of the mutant TR indicate that residues 29–35 are the most important for basolateral sorting from the biosynthetic pathway. The structural requirements for basolateral sorting of internalized receptors from the endocytic pathway are not identical. The most striking difference is that alteration of G31DNS34 to YTRF impairs basolateral sorting of newly synthesized receptors from the biosynthetic pathway but not internalized receptors from the endocytic pathway. Also, mutations have been identified that selectively impair basolateral sorting of internalized TRs from the endocytic pathway without affecting basolateral sorting of newly synthesized receptors. These results imply that there are subtle differences in the recognition of the TR basolateral sorting signal by separate sorting machinery located within the biosynthetic and endocytic pathways.


2000 ◽  
Vol 11 (8) ◽  
pp. 2775-2791 ◽  
Author(s):  
Raluca Gagescu ◽  
Nicolas Demaurex ◽  
Robert G. Parton ◽  
Walter Hunziker ◽  
Lukas A. Huber ◽  
...  

We present a biochemical and morphological characterization of recycling endosomes containing the transferrin receptor in the epithelial Madin-Darby canine kidney cell line. We find that recycling endosomes are enriched in molecules known to regulate transferrin recycling but lack proteins involved in early endosome membrane dynamics, indicating that recycling endosomes are distinct from conventional early endosomes. We also find that recycling endosomes are less acidic than early endosomes because they lack a functional vacuolar ATPase. Furthermore, we show that recycling endosomes can be reached by apically internalized tracers, confirming that the apical endocytic pathway intersects the transferrin pathway. Strikingly, recycling endosomes are enriched in the raft lipids sphingomyelin and cholesterol as well as in the raft-associated proteins caveolin-1 and flotillin-1. These observations may suggest that a lipid-based sorting mechanism operates along the Madin-Darby canine kidney recycling pathway, contributing to the maintenance of cell polarity. Altogether, our data indicate that recycling endosomes and early endosomes differ functionally and biochemically and thus that different molecular mechanisms regulate protein sorting and membrane traffic at each step of the receptor recycling pathway.


1999 ◽  
Vol 10 (12) ◽  
pp. 4369-4384 ◽  
Author(s):  
Som-Ming Leung ◽  
Raul Rojas ◽  
Christopher Maples ◽  
Christopher Flynn ◽  
Wily G. Ruiz ◽  
...  

Efficient postendocytic membrane traffic in polarized epithelial cells is thought to be regulated in part by the actin cytoskeleton. RhoA modulates assemblies of actin in the cell, and it has been shown to regulate pinocytosis and phagocytosis; however, its effects on postendocytic traffic are largely unexplored. To this end, we expressed wild-type RhoA (RhoAWT), dominant active RhoA (RhoAV14), and dominant inactive RhoA (RhoAN19) in Madin-Darby canine kidney (MDCK) cells expressing the polymeric immunoglobulin receptor. RhoAV14 expression stimulated the rate of apical and basolateral endocytosis, whereas RhoAN19 expression decreased the rate from both membrane domains. Polarized basolateral recycling of transferrin was disrupted in RhoAV14-expressing cells as a result of increased ligand release at the apical pole of the cell. Degradation of basolaterally internalized epidermal growth factor was slowed in RhoAV14-expressing cells. Although apical recycling of immunoglobulin A (IgA) was largely unaffected in cells expressing RhoAV14, transcytosis of basolaterally internalized IgA was severely impaired. Morphological and biochemical analyses demonstrated that a large proportion of IgA internalized from the basolateral pole of RhoAV14-expressing cells remained within basolateral early endosomes and was slow to exit these compartments. RhoAN19 and RhoAWT expression had little effect on these postendocytic pathways. These results indicate that in polarized MDCK cells activated RhoA may modulate endocytosis from both membrane domains and postendocytic traffic at the basolateral pole of the cell.


2015 ◽  
Vol 20 (5) ◽  
pp. 486-493 ◽  
Author(s):  
P. Muthuraman ◽  
P. C. Nagajyothi ◽  
M. Chandrasekaran ◽  
G. Enkhtaivan ◽  
B. Venkitasamy ◽  
...  

1996 ◽  
Vol 74 (2) ◽  
pp. 283-287 ◽  
Author(s):  
K. Randall ◽  
M. Lever ◽  
B. A. Peddie ◽  
S. T. Chambers

Intracellular accumulation of different betaines was compared in osmotically stressed Madin Darby canine kidney (MDCK) cells to model the betaine accumulation specificity of the mammalian inner medulla and to show how this accumulation differed from that of bacteria. All betaines accumulated less than glycine betaine. Arsenobetaine (the arsenic analogue of glycine betaine) accumulated to 12% of the glycine betaine levels and the sulphur analogue dimethylthetin accumulated to >80%. Most substituted glycine betaine analogues accumulated to 2–5% of intracellular glycine betaine concentrations, however, serine betaine accumulated to <0.5% of glycine betaine levels. Inhibition studies to distinguish the betaine ports were performed by the addition of proline. Butyrobetaine and carnitine accumulation was not proline sensitive, whereas that of omer betaines was. As with glycine betaine, the accumulation of propionobetaine and dimethylthetin was proline sensitive and osmoregulated. Pyridinium betaine was accumulated by both proline-sensitive and -insensitive systems, with a small increase under osmotic stress. High concentrations (10 times that of glycine betaine) of the dietary betaines proline betaine and trigonelline inhibited total betaine accumulation. Because α-substituted betaines are accumulated by bacteria and not by MDCK cells, these betaines may be the basis for design of antimicrobial agents.Key words: MDCK cells, betaine accumulation, osmolytes, betaine analogues.


1990 ◽  
Vol 18 (4) ◽  
pp. 255-258 ◽  
Author(s):  
W. L. Strohmaier ◽  
K. -H. Bichler ◽  
P. Deetjen ◽  
S. Kleinknecht ◽  
M. Pedro ◽  
...  

1994 ◽  
Vol 5 (10) ◽  
pp. 1093-1103 ◽  
Author(s):  
A K Rajasekaran ◽  
J S Humphrey ◽  
M Wagner ◽  
G Miesenböck ◽  
A Le Bivic ◽  
...  

Sorting of newly synthesized plasma membrane proteins to the apical or basolateral surface domains of polarized cells is currently thought to take place within the trans-Golgi network (TGN). To explore the relationship between protein localization to the TGN and sorting to the plasma membrane in polarized epithelial cells, we have expressed constructs encoding the TGN marker, TGN38, in Madin-Darby canine kidney (MDCK) cells. We report that TGN38 is predominantly localized to the TGN of these cells and recycles via the basolateral membrane. Analyses of the distribution of Tac-TGN38 chimeric proteins in MDCK cells suggest that the cytoplasmic domain of TGN38 has information leading to both TGN localization and cycling through the basolateral surface. Mutations of the cytoplasmic domain that disrupt TGN localization also lead to nonpolarized delivery of the chimeric proteins to both surface domains. These results demonstrate an apparent equivalence of basolateral and TGN localization determinants and support an evolutionary relationship between TGN and plasma membrane sorting processes.


1987 ◽  
Vol 7 (4) ◽  
pp. 1326-1337
Author(s):  
S L Warren ◽  
W J Nelson

Madin-Darby canine kidney (MDCK) cells form polarized, multicellular epithelial structures in vitro. Low-level expression of pp60v-src in MDCK cells elicits plasticity in these multicellular structures. Plasticity was revealed by the displacement of cells from mechanically stressed regions of the epithelial monolayers; however, the two-dimensional relationship between the cells in the remainder of the monolayer was maintained. Electron microscopy of multicellular structures revealed abnormal separation of the lateral membranes of adjacent cells and selective uncoupling of the junctional complex; the zonula adherens was disrupted, but the zonula occludens and desmosomes were retained. Significantly, this result was not accompanied by transformation of the cells, as judged by the absence of anchorage-independent growth potential. These results demonstrate a nonmitogenic biological activity of pp60v-src which is experimentally dissociable from transformation. This morphoregulatory action on higher-order epithelial structures may reflect a function of related cellular tyrosine kinases.


1999 ◽  
Vol 145 (1) ◽  
pp. 141-151 ◽  
Author(s):  
Rosa Puertollano ◽  
Fernando Martín-Belmonte ◽  
Jaime Millán ◽  
María del Carmen de Marco ◽  
Juan P. Albar ◽  
...  

The MAL (MAL/VIP17) proteolipid is a nonglycosylated integral membrane protein expressed in a restricted pattern of cell types, including T lymphocytes, myelin-forming cells, and polarized epithelial cells. Transport of the influenza virus hemagglutinin (HA) to the apical surface of epithelial Madin-Darby canine kidney (MDCK) cells appears to be mediated by a pathway involving glycolipid- and cholesterol- enriched membranes (GEMs). In MDCK cells, MAL has been proposed previously as being an element of the protein machinery for the GEM-dependent apical transport pathway. Using an antisense oligonucleotide-based strategy and a newly generated monoclonal antibody to canine MAL, herein we have approached the effect of MAL depletion on HA transport in MDCK cells. We have found that MAL depletion diminishes the presence of HA in GEMs, reduces the rate of HA transport to the cell surface, inhibits the delivery of HA to the apical surface, and produces partial missorting of HA to the basolateral membrane. These effects were corrected by ectopic expression of MAL in MDCK cells whose endogenous MAL protein was depleted. Our results indicate that MAL is necessary for both normal apical transport and accurate sorting of HA.


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