Linked Life Data

21307348

Source:http://linkedlifedata.com/resource/pubmed/id/21307348

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-5-27
pubmed:abstractText
Previously, we demonstrated that the vacuolar-type H(+)-ATPase (V-ATPase) a2-subunit functions as an endosomal pH sensor that interacts with the ADP-ribosylation factor (Arf) guanine nucleotide exchange factor, ARNO. In the present study, we showed that ARNO directly interacts not only with the a2-subunit but with all a-isoforms (a1-a4) of the V-ATPase, indicating a widespread regulatory interaction between V-ATPase and Arf GTPases. We then extended our search for other ARNO effectors that may modulate V-ATPase-dependent vesicular trafficking events and actin cytoskeleton remodeling. Pull-down experiments using cytosol of mouse proximal tubule cells (MTCs) showed that ARNO interacts with aldolase, but not with other enzymes of the glycolytic pathway. Direct interaction of aldolase with the pleckstrin homology domain of ARNO was revealed by pull-down assays using recombinant proteins, and surface plasmon resonance revealed their high avidity interaction with a dissociation constant: K(D) = 2.84 × 10(-10) M. MTC cell fractionation revealed that aldolase is also associated with membranes of early endosomes. Functionally, aldolase knockdown in HeLa cells produced striking morphological changes accompanied by long filamentous cell protrusions and acidic vesicle redistribution. However, the 50% knockdown we achieved did not modulate the acidification capacity of endosomal/lysosomal compartments. Finally, a combination of small interfering RNA knockdown and overexpression revealed that the expression of aldolase is inversely correlated with gelsolin levels in HeLa cells. In summary, we have shown that aldolase forms a complex with ARNO/Arf6 and the V-ATPase and that it may contribute to remodeling of the actin cytoskeleton and/or the trafficking and redistribution of V-ATPase-dependent acidic compartments via a combination of protein-protein interaction and gene expression mechanisms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1522-1563
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
300
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C1442-55
pubmed:meshHeading
pubmed-meshheading:21307348-ADP-Ribosylation Factors, pubmed-meshheading:21307348-Animals, pubmed-meshheading:21307348-Cell Shape, pubmed-meshheading:21307348-Cell Surface Extensions, pubmed-meshheading:21307348-Cytoplasmic Vesicles, pubmed-meshheading:21307348-Endosomes, pubmed-meshheading:21307348-Fructose-Bisphosphate Aldolase, pubmed-meshheading:21307348-GTPase-Activating Proteins, pubmed-meshheading:21307348-Gelsolin, pubmed-meshheading:21307348-Gene Knockdown Techniques, pubmed-meshheading:21307348-HeLa Cells, pubmed-meshheading:21307348-Humans, pubmed-meshheading:21307348-Hydrogen-Ion Concentration, pubmed-meshheading:21307348-Isoenzymes, pubmed-meshheading:21307348-Mice, pubmed-meshheading:21307348-Protein Subunits, pubmed-meshheading:21307348-RNA, Small Interfering, pubmed-meshheading:21307348-Vacuolar Proton-Translocating ATPases
pubmed:year
2011
pubmed:articleTitle
Aldolase directly interacts with ARNO and modulates cell morphology and acidic vesicle distribution.
pubmed:affiliation
Program in Membrane Biology and Nephrology Division, Center for Systems Biology, Simches Research Center, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural