EurekaMag.com logo
+ Translate

Polarized secretion of apoA-I and apoA-II by transfected MDCK cells


, : Polarized secretion of apoA-I and apoA-II by transfected MDCK cells. Journal of Lipid Research 36(3): 407-413

Apolipoproteins (apo) are secreted preferentially from the basolateral surface of hepatocytes and enterocytes. The polarized secretion of proteins is either mediated by a protein-dependent sorting signal or by a cell-dependent default pathway. In order to determine the mechanism for the polarized secretion of apolipoproteins, we examined the secretion of apoA-I and apoA-II in transfected Madin-Darby canine kidney (MDCK) cells. Transfected MDCK cells and Caco-2 cells were grown as a polarized monolayer on tissue culture inserts, which separate an upper apical compartment from the lower basolateral compartment, and the secretion of apoA-I and apoA-II into the apical and basolateral compartments was quantitated by immunoprecipitation. Caco-2 cells almost exclusively secreted apoA-I and apoA-II basolaterally, with an apical to basolateral ratio of 18:82 for apoA-I, and 11:89 for apoA-II. In contrast, transfected MDCK cells secreted significant amounts of apoA-I and apoA-II into both compartments, but with a bias toward apical secretion and an apical to basolateral ratio of 66:34 and 68:32, respectively. The polarized secretion of MDCK cells was not due to transcytosis, diffusion, or differential recovery. As assessed by density gradient ultracentrifugation, apoA-I and apoA-II secreted from either the apical or basolateral surface were relatively lipid-poor. Overall, these results suggest that the polarized secretion of apoA-I and apoA-II does not occur by a protein-dependent sorting signal, but by a cell-dependent default pathway that leads to preferential basolateral secretion by Caco-2 cells and both apical and basolateral secretion in MDCK cells, but with a bias toward apical secretion.

(PDF 0-2 workdays service)

Order PDF Full Text

Close
Close

Click here to order any other PDF Full Text


Accession: 009208274

PMID: 7775853

PDF Full Text: Submit


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Other references

Anonymous, 2013: Avalanche-like behavior in IFT. Cilia and flagella are microtubule-based organelles that protrude from the cell body. Ciliary assembly requires intraflagellar transport (IFT), a motile system that delivers cargo from the cell body to the flagellar tip for assembly. The process c...

Kuwata, T.; Miyazaki, Y.; Igarashi, T.; Takehisa, J.; Hayami, M., 1997: The rapid spread of recombinants during a natural in vitro infection with two human immunodeficiency virus type 1 strains. We quantified a population of recombinants in a natural in vitro infection, using wild-type viruses without any pressure. It was found that recombinants emerged early after infection and constituted more than 20% of the whole proviral population 1...

Smithberg M.; Dixit P.K., 1981: Is lithium teratogenic. Teratology 23(2): 63A

Katsev, A. M.; Onuchina, I. G.; Gordienko, A. I.; Beloglazov, V. A., 2002: Study of the binding between bacterial lipopolysaccharides and polymixin by bioluminescent method. For rating the interaction of lipopolysaccharides (LPS) with polymixin B (PmB) a bacterial bioluminescence is offered to be used. Bioluminescence level of bacteria decreases under free antibiotic amounts action. It is shown, that as a result of in...

Polyakova, V.; Sushko, V., 2000: Microorganisms in brochial mucosa of the Chernobyl accident consequences liquidators. Pathology International 50(Supplement): A74, October

Thulin J., 1973: Some parasites in a sunfish caught in gothenburg sweden harbor. Zoologisk Revy 35(2): 82-84

Imre, S. G.; Fekete, I.; Farkas, T., 1994: Increased Proportion of Docosahexaenoic Acid and High Lipid Peroxidation Capacity in Erythrocytes of Stroke Patients. Background and Purpose: Intracellular accumulation of lipid peroxides that derive from the autoxidation of membrane polyunsaturated fatty acids reduces the deformability of erythrocytes contributing to the hemorheological disturbances observed in...

Vermeulen, J.; Parra, E., 1982: Effectiveness of acaricides for the control of European red spider mite (Panonychus ulmi, K.). Spraying Red Delicious apple trees with either OSA AC-666 (0.025% a.i.) [cyhexatin], 50% SN.84.866 (0.03% a.i.) [unspecified], 50% Dicarzol (0.05% a.i.) [formetanate] or Dicarzol + SN.84.866 (0.025 + 0.03% a.i.) gave 99.6, 73.0, 68.4 and 50.5% con...

Hadlock Charles R., 1983: Criteria for nuclear waste repositories. Abstracts with Programs - Geological Society of America 15(6): 588

Wallace, Arthur, 1994: Ignorance and poverty are barriers to sustainable agriculture. Ignorance and poverty are barriers to sustainable agriculture and a healthy environment. Poverty is easily defined but ignorance is more complex; interrelationships among disciplines is a common area of ignorance. Poverty and ignorance do not alwa...