Linked Life Data

21828182

Source:http://linkedlifedata.com/resource/pubmed/id/21828182

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2011-9-22
pubmed:abstractText
The vasopressin receptor type 2 (V2R) is the major target of vasopressin (VP) in renal epithelial cells. Although it is known that VP induces V2R internalization, accumulation in the perinuclear area, and degradation, the V2R intracellular trafficking pathways remain elusive. We visualized this process by developing a new fluorescent VP analog tagged by tetramethylrhodamine (TMR)-[Lys-(PEG)(2)-Suc-TMR(8)]VP or (VP(TMR)). This ligand is fully functional as revealed by its high binding affinity toward V2R [(K(d)) =157 ± 52 nM] and ability to increase intracellular cAMP 32-fold. VP(TMR) induced V2R internalization in LLC-PK1 cells expressing either a FLAG-tagged receptor (FLAG-V2R) or V2R C-terminally tagged with green fluorescent protein (GFP) (V2R-GFP). After internalization, VP(TMR) and V2R-GFP colocalized in the perinuclear area, suggesting that the hormone and receptor traffic along the same pathway. VP(TMR) and V2R colocalized initially with the early endosome markers EEA1 and Rab5, and later with the recycling and late endosome markers Rab11 and Rab25. Epifluorescence microscopy of LLC-PK1 cells expressing GFP-tagged microtubules (MT) showed that VP(TMR)-containing vesicles travel along the MT network, and even remain attached to MT during the metaphase and anaphase of mitosis. Colchicine, a MT-depolymerizing agent, abolished perinuclear accumulation of VP(TMR), and Western blot analysis showed that VP-induced V2R-GFP degradation is markedly retarded, but not abolished, by colchicine (10 ?M). We conclude that the new VP(TMR) ligand is suitable for dissecting V2R and VP internalization and trafficking in cells, and that V2R trafficking and down-regulation is an MT-dependent mechanism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1945-7170
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
152
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3893-904
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Visualizing microtubule-dependent vasopressin type 2 receptor trafficking using a new high-affinity fluorescent vasopressin ligand.
pubmed:affiliation
Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural